Topics
Contents Rapid communications, 826 Article(s)
Xiaoming Xi, Peng Wang, Baolai Yang, Chen Shi, Zilun Chen, Pengfei Ma, Hanwei* Zhang, Xiaolin** Wang, Zefeng Wang, Wenguang Liu, Kai Han, Pu Zhou, Xiaojun Xu, and Jinbao*** Chen

Acta Optica Sinica
Nov. 25, 2022, Vol. 42 Issue 22 2238001 (2022)
2D Imaging Experiment of a 2D Target in a Laboratory-Scale Synthetic Aperture Imaging Ladar
Zhou Yu, Xu Nan, Luan Zhu, Yan Aimin, Wang Lijuan, Sun Jianfeng, and Liu Liren

The 2D imaging in both the azimuth and the range directions of a 2D target is realized in our laboratory-scale synthetic aperture imaging ladar setup. It was reached that the scan strip of ≤10 mm and the resolution of about 1.2 mm×2 mm.

Acta Optica Sinica
Jun. 19, 2020, Vol. 29 Issue 7 2030 (2009)
Two-Dimensional Imaging Experiment of a Point Target in a Laboratory-Scale Synthetic Aperture Imaging Ladar
Zhou Yu, Xu Nan, Luan Zhu, Sun Jianfeng, and Liu Liren

The 2D imaging in both the azimuth and the range directions of a point target is realized in our laboratory-scale synthetic aperture imaging ladar setup. The experimental results are identical with the predicted.

Acta Optica Sinica
Jun. 19, 2020, Vol. 29 Issue 2 566 (2009)
Aperture-Synthesizing Experiment of a Down-Scaled Synthetic Aperture Imaging Ladar
Zhou Yu, Sun Jianfeng, Luan Zhu, and Liu Liren

A down-scaled synthetic aperture imaging ladar (SAIL) is designed to simulate the condition of the far-field diffraction on the table of laboratory, and the techniques to monitor the qualifications of wavefront and heterodyne are developed, As a result, a target point is imaged along the azimuth direction with aperture synthesizing. The experimental results are identical with the theoretical predictions.

Acta Optica Sinica
Jun. 18, 2020, Vol. 28 Issue 12 2446 (2008)
Optimized Design of 3-Skip-1 Filter for 100 GHz Used in Optical Add-Drop Multiplexing
Duan Yuhua, Jing Xili, and Song Chaoqun

An optimized algorithm based on simulated annealing and genetic algorithm was provided for designing films of 3-skip-1 filters. Two antireflection layers were added to the exterior of the stack to deminish the ripple of passband. The optimized multilayer film meets the design demand of 3-skip-1 filter of 100 GHz.

Acta Optica Sinica
Jun. 18, 2020, Vol. 28 Issue 11 2243 (2008)
Wavefront Curvature Sensor with Phase Defocus Grating
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The wavefront curvature sensor comprising a phase defocus grating is designed and fabricated. The influence of zero-order diffraction is prohibited, and the high diffractive efficiency of 49% for the ±1 diffraction orders is verified experimentally. Wavefront deformation is introduced by a phase plate. The initial wavefront measurement experiment is carried out. The Green function algorithm is used for wavefront reconstruction. The reconstructed wavefront is compared with the measurement result of the Veeco interferometer. It is verified that the measurement of the self-designed curvature sensor is correct, the error percent of peak-valley value (PV) is 10%, and the error percent of root mean square (RMS) is 2%.

Acta Optica Sinica
Jan. 01, 1900, Vol. 27 Issue 2 377 (2007)
Generation of High-Order Harmonic Continuum Supporting Single Attosecond Pulse in Argon Driven by Intense 7 fs Laser Pulse
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Highorder harmonic continuum in the cutoff region is demonstrated with an argon gas cell driven by 7 fs/0.4 mJ ultrashort intense laser pulses. It is found that the spectral structure, modulation depth and continuum bandwidth vary greatly when the carrier envelope phase (CEP) of driving laser pulse is stabilized at different value. At some CEP value, a smooth continuous spectrum with modulation depth less than 17% and 10 eV continuum bandwidth is achieved, supporting a transformlimited single 500 as pulse in time domain.

Acta Optica Sinica
Jan. 01, 1900, Vol. 26 Issue 9 1439 (2006)
Coherent Output Power of 60 W from Two Large-Core Double-Cladding Fiber Lasers
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A phase-locking fiber laser array with up to 60 W of coherent output power based on two large-core fiber is reported. The slope efficiency of the in-phase mode is 37%. For the two core space cases, the steady high-contrast interference strips are observed. When the whole system operates under high pump power level, no thermal effects for the spatial filter have been observed, which means that we can increase the coherent output power further by increasing the individual fiber laser power.

Acta Optica Sinica
Jan. 01, 1900, Vol. 26 Issue 8 1279 (2006)
A Continuous-Wave 714 W Fiber Laser With China-Made Large-Mode-Area Double-Clad Fiber
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A continuous-wave (CW) fiber laser with 714 Watts output power has been obtained from 21 meters Chia-made Ytterbium-doped large-mode-area double-clad fiber. Two high-power collimated beam laser diodes (wavelenth 976 nm) with spatial filter and aspheric lens are used for pumping from the two ends of the fiber. A CW output power of 501 W is obtained under pump power of 760 W with backward pumping scheme. And the maximum output power of 714.5 W is realised under total pump power of 1137 W with double-sided end-pumping scheme, the optical-to-optial efficiency and the slope efficiency whicd respect to the launched pump power are 62.8% and 67%, respectively.

Acta Optica Sinica
Jan. 01, 1900, Vol. 26 Issue 7 1119 (2006)
Laser Diode-Pumped Efficient Tunable YbLYSO Laser
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

We demonstrate continuous-wave laser action in a Yb3+-doped lutetium Yttrium oxyorthosilicate (YbxLuyY1-x-y)2SiO5(YbLYSO) crystal (0.001≤x≤0.5, 0≤y≤0.8). In the free-running operation, we obtained an output power as high as 7.8 W centered about 1086 nm for a 2.5% output coupler, corresponding to a slope efficiency of 64%. Using a SF14 prism as an intracavity tuning element, the tunability of the YbLYSO laser in the spectral range of 1014~1091 nm has been achieved.

Acta Optica Sinica
Jan. 01, 1900, Vol. 26 Issue 5 799 (2006)
10.5 W Continuous-Wave Output from Yb∶Y2O3 Ceramic Disk Laser
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A contimuous-wave (CW) output has been obtained from a polycrystalline 8% mole ratio Yb∶Y2O3 ceramic disk laser with end-pumping and double-pass absorption cavity, which is end-pumped by a collimated high-power laser diode with the central wavelength located at 970 nm, at room temperature. The threshold pump power of the laser is 7 W, and under pump power of 35 W a CW output power of 10.5 W at 1078 nm is obtained, with optical-optical conversion efficiency of 30% and slope efficiency of 37.5%. There exists a rough linear rise for the output power with the pump power. The higher output power and efficiency can be expectable by adopting higher pump power, optimizing the cavity parameters and decreasing influence of thermal effect.

Acta Optica Sinica
Jan. 01, 1900, Vol. 26 Issue 5 797 (2006)
ZnO Thin Films Prepared by PECVD from Mixture Sources of Metalorganic Zinc and Carbon Dioxide-Hydrogen Gas
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

ZnO films are prepared by plasma enhanced chemical vapor deposition (PECVD), using carbon dioxide-hydrogen gas and diethylzinc gas as reactant sources. Carbon dioxide reacts with hydrogen in the plasma charmer to produce oxygen source. Crystallographic properties and surface morphology of the films are characterized by X-ray diffraction (XRD) and atomic force microscopy (AFM). The results indicate that the wurtzite structure of ZnO thin films with a strong c-axis orientation is successfully deposited on Si substrate. AFM images show that the grains arrange regularly and roughness of the surface is very small. A type emission peak at 380 nm of ZnO is also observed from photoluminescence (PL) spectrum.

Acta Optica Sinica
Jan. 01, 1900, Vol. 26 Issue 4 639 (2006)
Highly Efficient Bright Red Organic Electrophosphorescent Device
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A highly efficient bright red electrophosphorescent device using bis(2-methyl-8-quinolinato)4-phenylphenolate aluminum (BAlq) as a hole and exciton blocker is reported. Maximum luminance and external quantum efficiency of the device are 10362 cd/m2 and 7.0% respectively. Commission Internationale de l′Eclairage (CIE) co-ordinates are (0.672, 0.321). In addition, the quantum efficiency is still as high as 4.3% at a current density of 100 mA/cm2. The device can satisfy the requirement of the red in the full color dynamic displays.

Acta Optica Sinica
Jan. 01, 1900, Vol. 25 Issue 5 719 (2005)
Research on an Offset-type Micro Mechanical Variable Optical Attenuator
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A variable optical attenuator (VOA) fabricated by micro mechanical technology is presented. Based on micro electromagnetic actuation, the attenuation level is adjusted by changing the radial offset between the input and output optical fiber. The structure parameter was determined through optics, mechanics and magnetic circuit analysis. The device was fabricated and packaged by micromachining technology. The packaged volume of the device is 20 mm×15 mm×8 mm. According to the experiment results, the insertion loss is less than 1 dB, the polarization relevant loss is less than 0.1 dB, dynamic range is larger than 35 dB and the driving voltage is less than 5 V. It promises to be a low cost, high performance passive device for all-optical-networks.

Acta Optica Sinica
Jan. 01, 1900, Vol. 25 Issue 5 717 (2005)
Experimental Study of Ultraviolet Laser-Induced Domain Reversion in LiNbO3 Crystals
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A method of realizing ultraviolet (UV) laser induced domain reverse in LiNbO3 crystals is investigated experimentally. With a certain external electric field, a sample of LiNbO3 crystal is illuminated by a UV laser beam of 365 nm wavelength. For the reason that the coercive field of the crystal is decreased by exposure of UV light, it is only the illuminated region whose domain is reversed. The results prove that this method can be used to realize the fabrication of periodically poled LiNbO3 crystals, and it will become an effective solution to smaller periods.

Acta Optica Sinica
Jan. 01, 1900, Vol. 25 Issue 3 431 (2005)
Infrared Scintillation Properties of Yb∶YAG Crystal
[in Chinese], [in Chinese], and [in Chinese]

Infrared (IR) scintillation properties of Yb∶YAG crystals with different Yb3+ doping level were measured by using pulsed electron beam. At room temperature the light yield of Yb∶YAG crystal is high and decay time is long. The dependence of light yield and decay time on Yb3+ doped concentration and temperature were demonstrated, and concentration quenthing was observed. The scintillation properties of Yb∶YAG were still affected by crystal quality. These measurement results suggest that some Yb3+-doped crystals should be possible for application in medical imaging.

Acta Optica Sinica
Jan. 01, 1900, Vol. 25 Issue 3 429 (2005)
Fabrication of Soft X-Ray Phase Condenser Zone Plates
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Soft X-ray zone plate is an important element which has the function of concentration, dispersion and imaging in soft X-ray optics. An Au condenser phase zone plate mask is fabricated using holography and ion beam etching process. Soft X-ray Ge and Ni condenser phase zone plates are fabricated by ion-beam etching technology on polyimide substrate and contact synchrotron radiation lithography with the mask.

Acta Optica Sinica
Jan. 01, 1900, Vol. 25 Issue 12 1722 (2005)
Experimental Results of X-Ray Diffraction Enhanced Phase Contrast Imaging
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Some experimental results and the principle of X-ray diffraction enhanced phase contrast imaging are presented. It demonstrates that X-ray diffraction enhanced phase contrast imaging is an approach with higher ratio of signal-to-noise than that of traditional X-ray radiography, the resolution can be up to 10 μm. It's a promising tool for the applications in researches on clinical, medicine and material sciences.

Acta Optica Sinica
Jan. 01, 1900, Vol. 24 Issue 8 1151 (2004)
5 W CW Output Yb3+:Y2O3 Transparent Ceramic Laser
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

CW laser output is obtained using laser diode end-pumped polycrystalline transparent 10% Yb3+∶Y2O3 ceramic. The pump threshold is 5.6 W, the maximum output power of 5.48 W is obtained with the absorbed pump power 31.11 W, and the slope efficiency is as high as 25%. At the same time there is no saturation in laser experiment, so the higher power output of Yb3+∶Y2O3 ceramic can be obtained with laser diode of higher power. Therefore Yb3+∶Y2O3 ceramic is a potential laser material.

Acta Optica Sinica
Jan. 01, 1900, Vol. 24 Issue 3 431 (2004)
A Descriptive Method for Image Stability
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A mathematical model, which describes stability of imaging system, is provided. While objects consist of two kinds of brightness and have periodic structure, it is proved, that intensity of pixel on image sensor of unstable image system accords binomial distribution. So image statistical parameter can be applied to describe system velocity and image instability. In order to research the rule of image stabilization at different times, the standard deviation, which indicates discrete degree of data in statistics, is introduced as descriptive factor. Finally, the curve, which described transformation process of Pechan prism system, is given. The fluctuation of the curve is in accordance with the stability change of observed image. This conclusion proves the provided method is reasonable and effective.

Acta Optica Sinica
Jan. 01, 1900, Vol. 24 Issue 3 427 (2004)
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 24 Issue 12 1705 (2004)
Supercontinuum Generation in Photonic Crystal Fiber by Femtosecond Pulses Laser
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Supercontinuum light with a spectrum covering visible range was generated in a photonic crystal fiber launched by the 25 fs laser pulse train from a Ti: sapphire laser oscillator at 800 nm wavelength. The fiber has a core diameter of ~1.8 μm and a length of 10 mm. By setting the laser energy at 2.5 nJ, it corresponds a peak power of about 0.1 MW, respectively, coupling efficiency of 17% was demonstrated.

Acta Optica Sinica
Jan. 01, 1900, Vol. 23 Issue 4 511 (2003)
An Autocorrelator Based on ZnSSe Two-Phonton Absorption Photodetectors
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

An autocorrelator based on ZnSSe two-photon absorption (TPA) photodetectors is demonstrated. The autocorrelator has a broad spectral response range of 400~800 nm. By using a ZnMgS TPA photodetector which is more sensitive to UV laser, the autocorrelator′s response range can be extended further to the ultraviolet waveband.

Acta Optica Sinica
Jan. 01, 1900, Vol. 23 Issue 2 255 (2003)
Numerical Analysis on Spatial Three-Position-Pumped Yb-Doped Double-Cladding Fiber Laser
[in Chinese], [in Chinese], and [in Chinese]

Based on the numerical analysis of spatial different three-position-pumped situations, the research was carried out on the Yb-doped double-cladding fiber laser containing amplified spontaneous emission. The results show the different laser distribution and power characteristics for different three-position-pumped situations, even ignoring the reflection of the resonator to the pump light.

Acta Optica Sinica
Jan. 01, 1900, Vol. 23 Issue 2 249 (2003)
Semiconductor Saturable-Absorber Mirror for Self-Starting Mode-Locked Ti:Sapphire Lasers
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The low-loss broadband semiconductor saturable absorber mirror (SESAM) is firstly designed and manufactured in China. This SESAM has been used in self-starting mode-locked Ti:sapphire lasers.

Acta Optica Sinica
Jan. 01, 1900, Vol. 22 Issue 9 1151 (2002)
Passive Q-Switching of 0.946 μm Nd3+:YAG Laser with Cr4+:YAG Saturable Absorber
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

With Cr 4+:YAG as the saturable absorber and xenon flash lamp as the pumping source, passively Q-switched quasi-three-level laser operation of Nd 3+:YAG at 0.946 μm is realized. Pulses with a width of 38 ns and an energy of 1.7 mJ are obtained.

Acta Optica Sinica
Jan. 01, 1900, Vol. 22 Issue 9 1149 (2002)
40 Gbit/s OTDM System with Unequal Amplitude Coding Methods
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A 40 Gb/s optical time division multiplexing (OTDM) system is presented and discussed. Frame structure of OTDM data stream is designed based on unequal amplitude coding methods. Gain-switched distributed-feedback laser (GS-DFB) and comb-like dispersion profiled fiber (CDPF) are employed to generate the ultra-short optical pulses; chirped fiber grating for dispersion compensation; electro-absorption modulator (EAM) for de-multiplexing the 40 Gbit/s data stream. The frame clock (10 GHz) is extracted from the data stream with high Q value electronic filter. After transmission over 122 km single mode fiber (SMF), bit error rate of the whole system is less than 10 -9.

Acta Optica Sinica
Jan. 01, 1900, Vol. 22 Issue 9 1145 (2002)
Phosphorescence Lifetime Measurement Independent on the Parameters of the Excitation Light Pulse
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

In the phosphorescence lifetime measurements with pulse method, both the excitation light pulse parameters and initial time selected for intensity decay analysis are crucial to the accurate lifetime calculation. The relation between phosphorescence intensity decay and the parameters of the excitation light pulse is analyzed based on the linear time invariance. it is found that the phosphorescence intensity decay is independent on the parameters of the excitation light pulse after the excitation light vanishing. If the excitation light pulse vanishing moment is selected as the initial time, the accurate lifetime can be obtained. The experimental results from the Oxy-Phor R2 samples excited by different excitation light pulse have proved the above conclusion.

Acta Optica Sinica
Jan. 01, 1900, Vol. 22 Issue 9 1141 (2002)
Optical Properties of Oxygen-Doped Ge-Sb-Te Phase-Change Films
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Optical properties of monolayer oxygen-doped Ge-Sb-Te thin films prepared by RF-sputtering method were studied in the region of 400 nm~800 nm, including refractive index, extinction coefficient, reflection and transmission spectra. The results indicated that larger reflectivity contrast can be achieved by appropriate doping of oxygen, thus the recording properties of the Ge-Sb-Te film material can be improved by the oxygen-doping.

Acta Optica Sinica
Jan. 01, 1900, Vol. 22 Issue 9 1137 (2002)
Preparation of Green Sensitive Photopolymer and Investigation of Its Holographic Data Storage Characteristics
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A new type of green light sensitive photopolymer material is prepared. The photosensitive medium is composed of acrylamide monomer, photoinitiator, coinitiator and polymeric film forming binder. With holograms recorded in this material, the diffraction efficiency of the photopolymer as high as 55% is obtained. 10 holograms are stored in this medium using angular multiplexing technology and the SNR of the reconstruction images is high. It proves that the photopolymer is suitable for high density volume data storage.

Acta Optica Sinica
Jan. 01, 1900, Vol. 22 Issue 8 1021 (2002)
Line-Shape Changes of Na Resonance Fluorescence Due to Na-Na Collisions
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

In a dense Na vapor, the changes were observed in the Doppler broadened shape of the resonance fluorescence produced by the combined effect of the induced optical pumping and Na Na collisions. The observed narrowing of the fluorescence line shape was explained by a rate equation with "velocity change collision" effect.

Acta Optica Sinica
Jan. 01, 1900, Vol. 22 Issue 7 893 (2002)
Effect of Chirped Pulse on Phase Distortion in Second Harmonic Generation
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The effect of a chirped pulse in the process of second harmonic generation is discussed. The chirp influences the irradiance and the pulse shape of the second harmonic wave with large phase mismatch. The phase distortions of all three waves are dependant strongly on the chirp than on the phase mismatch.

Acta Optica Sinica
Jan. 01, 1900, Vol. 22 Issue 7 890 (2002)
The Study on Confidential Local Net Telecommunication Applying Polarized Light
[in Chinese], [in Chinese], and [in Chinese]

The polarity of light transmitted in polarization maintaining optical fibers of a confidential telecommunication system is dependent on artificial and environmental interfere to the fiber. The polarity may be taken as sensing parameter to detect in real time the wiretapping to the telecommunication. The threshold of wiretapping detecting is defined by the bend radius of the fiber, the typical value is 8.5 mm.

Acta Optica Sinica
Jan. 01, 1900, Vol. 22 Issue 3 383 (2002)
Reflectivity Calibration of Soft X-Ray Planar Mirror in the BSRF
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The calibration experiment of glancing incidence soft X ray planar mirror reflectivity is reported. The Beijing synchrotron radiation facility(BSRF) 3W1B beam line and target chamber with reflectometer was used. Under the specific operation mode of beam current 35 mA~110 mA, the storage ring electron energy 2 GeV, photon energies 50 eV~850 eV. 50 eV~850 eV energy region was divided into four energy sections. The calibration experiment for reflectivity of 5° grazing incidence Ni planar mirror was done. High sensitivity silicon photodiode without dead layer was used as detector replacing X ray diode during the calibration. Therefore,2 to 3 orders of magnitude of the signal noise ratio are increased, and the calibration region is expanded from 150 eV~270 eV to 50 eV~850 eV. The entire calibration curve for 5° Ni planar mirror reflectivity is given. The values of experiment and theoretical calculation are compared and analyzed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 22 Issue 3 379 (2002)
20 GHz Injecting Mode Locked Fiber Laser
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The optical source of stable and wavelength tunable ultrashor pulse is the key technique for the future OTDM/WDM systems. In this paper, an experiment with 20 GHz injecting mode-locked fiber laser is reported. With a source of 10 GHz semiconductor diode laser, a stable injecting mode-locked fiber laser producing 12.4 ps pulses at a rate of 20 GHz with the tunable range of 16 nm is got.

Acta Optica Sinica
Jan. 01, 1900, Vol. 22 Issue 2 253 (2002)
Dynamic Argument Using Shift Phase Interferometry
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The method of measuring new first-grade gauge block by phase-shift interferometry has been studied. Firstly, multi-frame interference patterns are captured by CCD, then the shape of the measured surface of the gauge and the assistant reference flat to be wrung are obtained by phase-shift arithmetic. In particular, the unwrapping wavefront principle and technology are studied when there are step and discontinuity in the gauge interference patterns. The discrete wave error is calculated, which is fitted to be a continuous and smooth surface. The measurement results of guage block length and dynamic argument are given.

Acta Optica Sinica
Jan. 01, 1900, Vol. 22 Issue 2 249 (2002)
Effects of Relative Amplitude and Phase on Phased Array System and Their Elimination
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The principle of localization of a small object in tissues using an amplitude cancellation phase modulation system (or phased-array system) is explained by an analytical model of the diffusion approximation. The effects of various factors on localization of the object using Phased-array system are discussed, which include the relative phase and the amplitude between two sources, the absorption coefficient and the size of absorbers. A localization method independent of the relative amplitudes and phase between two sources is presented. The principle of the method is explained and its feasibility is proved theoretically.

Acta Optica Sinica
Jan. 01, 1900, Vol. 22 Issue 2 243 (2002)
The High Resolution Absorption Spectra of Atmosphere Measured by Laser Long Path Absorption Spectroscopy
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The high-resolution absorption spectra of real and simulated atmosphere were recorded by using an experimental system, which includes a tunable pulsed OPO, an 8 m base-length white cell with optical length of 1 km, and a time-division multiplexing detector system. The sensitivity is 0.5×10 -6 cm -1 and resolving power is 0.02 cm -1. The high-resolution absorption spectra of real atmosphere near 1.315 μm have been measured and compared with the simulated spectra according to HITRAN 96 database. The strong lines of water vapor molecule fit very well and the relative errors of molecular line intensity of the most strong lines are less than 10%.

Acta Optica Sinica
Jan. 01, 1900, Vol. 22 Issue 2 238 (2002)
Femtosecond Laser Induced BaTiO3 Crystal Precipitation in Glass
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

BaTiO 3 crystal was precipitated in BaO TiO 2 SiO 2 based glass irradiated by femtosecond laser with 800 nm wavelength, 120 fs pulse duration and 200 kHz repetition. During the irradiation, the luminescense color of irradiated point can be changed from 800 nm wavelength characterized red color to blue color. Luminescence spectra and X-ray diffraction of the irradiated point illustrate the formation of double frequency BaTiO3 crystal in the glass.

Acta Optica Sinica
Jan. 01, 1900, Vol. 22 Issue 10 1279 (2002)
Control of Unit Amplifier Gain in Built-up Double-Pass Coaxial Amplifiers
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

In accordance with the built-up structure of the main amplifier in "SHENGGUANG Ⅱ" laser system, a new scheme of using angular variable mirror (AVM) to control unit amplifier gain for power balance is proposed. The gain change of double-pass amplifier caused by the AVM attenuation is analysed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 22 Issue 1 126 (2002)
Propagation Characteristics of Lightwave in Side-Polished Poled Fibers
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

On the basis of configuration of side-polished poled fiber, a model of six-layer waveguide with double metal layers is put forwavd to describe the poled fiber and analyze the propagation characteristics of lightwave in the poled fibers. The analysis indicated that the lightwave propagating in the poled fiber has characteristics of polarization extinction due to the existence of metal electrodes deposited on the flat of the optical fiber. The main parameters of the device that affects the propagation characteristics of poled fiber are the distance between the core and polished flat, and the thickness of insulator adjacent to the anode.

Acta Optica Sinica
Jan. 01, 1900, Vol. 22 Issue 1 121 (2002)
Computer Generated Holography Wavefront-Transforming Element Fabrication by Binary Optical Technique
[in Chinese], and [in Chinese]

A computer generated holography (CGH) wavefront transforming element is designed and fabricated based on computer generated hologram and binary optical technique,and is applied in head up display. Its diffraction efficiency is very high. The diffraction efficiency of a two phase CGH is four times higher than that of a general CGH. It can generate special optical wavefront, such as aspheric surface, ring shaped surface, cone shaped surface and so on,which the traditional optical elements can not generate. Moreover, the fabrication and duplication techniques of CGH are simple and convenient.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 9 1150 (2001)
All-Solid-State Pumped Tunable PPLN Optical Parametric Oscillator
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A widely tunable quasi phase matched optical parametric oscillator was demonstrated by using periodically poled LiNbO 3 (PPLN) with a multigrating structure. With a 1064 nm acousto optically Q switched Nd∶YVO 4 pump laser, a tunable IR output from 1.436 μm to 1.7 μm was obtained. The threshold was 10.3 μJ with pulses repetition rate of 10 kHz. The maximum average output power of signal is 42.5 mW with pump to signal conversion efficiency of 12.5%.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 9 1148 (2001)
Design of Wide Waveband Wavelength-Insensitive Coupler Using Statistical Optimum Method
[in Chinese], [in Chinese], and [in Chinese]

A statistical optimum design method suitable for wide waveband wavelength insensitive coupler (WINC) is proposed. Using the method, silica waveguides type 50% and 20% coupling ratio WINCs are designed with the optimization of the polarized light fluctuation. The design results are verified by the 3D BPM simulation, and show that the coupling ratios of (50±2.1)% (the polarized fluctuation <0.65%) and (20±1.4)% (the polarized fluctuation <0.20%) in a wide wavelength region of 1280 nm~1650 nm are realized, respectively.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 8 996 (2001)
Analysis of Bragg Grating-Assisted Optical Fiber Symmetric Couplers Employing the Unified Coupled-Mode Theory
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The unified coupled mode formalism derived from Maxwell′s equation is employed to analyze the Bragg grating assisted optical fiber symmetric couplers. In the theoretical analysis, the coupling effects due to Bragg grating and coupler are both considered in the Bragg grating region, which is distinct from the previous published approaches. The simulating results verify that the theory can give more accurate explanation to various experimental phenomena.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 8 990 (2001)
A Fiber Bragg Grating Sensor System with Interferometric Demodulation Technique
[in Chinese], [in Chinese], and [in Chinese]

Based on the interferometric demodulation technique, a fiber Bragg grating sensor system employing an unbalance wavelength scanning Michelson interferometer to transpose the strain related spectral signal into phase signal is reported. The strain can be recovered by measuring the phase change of the signal with a phase-meter. Experiment demonstrated that the sensing sensitivity of this system with a resolution of 5.5 nε is 1.80° /με. It basically matches the prospected value of 1.83° /με.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 8 987 (2001)
Vector Analysis of Two-Dimensional Surface-Relief Structure Diffraction
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

By using of effective medium theory, the reflective efficiency of two dimensional surface relief structure is computed and analysised in various conditions through computation of rigorous coupled wave method. Several curves are presented in various conditions. Effective medium index of that structure is computed when plane wave normalized on the structure. It is indicated that variation of orientation and polarization angle make less effect on reflectivity for both symmetric or asymmetric structure. The result giving characteristic of anti polarization and anti reflective is obtained. The bandwidth limitation is analysised and its magnitude is given. While, the effect of manufacture error of relief height on reflectivity is analysised. It has a certain instruction significance to the practical work.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 8 980 (2001)
Effect of Wavelength Dependence of Reflectivity at AR-Coating Facets on Tuning Range of External-Cavity Semiconductor Lasers
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Wavelength dependence of reflectivity at AR coating facets has been taken into account to study the wavelength tuning range of the external cavity semiconductor lasers. By applying the equivalent cavity method, an analytical expression for the threshold carrier density varied with wavelength has been derived. Analysis shows that the deviation between the wavelength of minimum reflectivity at the AR coated facets and that of the gain peak before AR coating is a key parameter to increase wavelength tuning range.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 8 975 (2001)
The Selection of Injection Current of the External Cavity Laser Diode for All-Optical Wavelength Conversion
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The influence of external optical injection on the threshold current of external cavity laser diode with fiber Bragg grating is investigated experimentally. In order to obtaining high extinction ratio and high conversion rate simultaneously, the injection current range is determined. The experimental results are analyzed by carrier depletion mechanism.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 8 970 (2001)
Three-Dimensional Temperature Distribution Analysis and Thermal Lens Effect Calculation for High Power Laser Windows
[in Chinese], and [in Chinese]

Heat absorption of high power laser windows is analysed and the heat equation of the window for practical working device and its solving condition are given. Physical state of the high power laser is simplified suitable for the pratical condition. Analytic solution of the heat equation is given. Then the thermal lens effect of high power laser windows is calculated considering the thermal changes of refractive index of the window material and linear expanding index, and the result is disscussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 8 965 (2001)
Experiments of Laser Induced Collision Energy Transfer
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Laser induced collision energy transfer (LICET) for transition from Eu (6s6p) 8P 9/2 to Sr (5s10s) 1S 0 is observed at fluorescence 458.42 nm and with the peak transfer wavelength of 459.75 nm.The quasi static wing of LICET is observed and the dependence of the excitation function spectral on the temperature and the intensity of transfer laser is investigated. The experimental cross sections of LICEF is measured and the asymmetrical spectral line of LICET is confirmed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 8 961 (2001)
Optical Characteristics Analyses of Thin Film SO2 Gas Sensor
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The optical sensitive characteristic of SnO 2 and VO x thin films to the gas SO 2 is investigated with photometric and ellipsometric methods. It is found that thin films of the Pd doped SnO 2 and no dopant VO x have good optical sensitive characteristics to the gas SO 2 in the visible range, and the Zr doped SnO 2 film in the near infrared area. The results show that the change of the optical characteristic is directly related to the variation of optical gap and the concentration of free carrier in the thin films.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 8 957 (2001)
Effect of Film Thickness on Optical Properties of AgInSbTe Phase-Change Films
[in Chinese], [in Chinese], and [in Chinese]

The dependence of the optical properties on the thickness of AgInSbTe phase change films is investigated. The reflectivity, absorptivity, thickness and optical constant of the films were measured. The change of the extinction coefficient and refractive index become significant when the film is very thin, and become larger at shorter wavelengths such as in blue and green region. These results are very useful in improving the accuracy of optical design and simulation of AgInSbTe phase change optical disks, as well as in the study of phase change optical disks at shorter wavelengths.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 8 952 (2001)
Spectral and Optical Recording Properties of a Novel Subphthalocyanine Thin Film
[in Chinese], [in Chinese], and [in Chinese]

A novel bromoboron trinitro subphthalocyanine (BTN SubPc) thin film has been developed by vacuum evaporation for write once optical recording. The absorption and reflection properties of the sublimated BTN-SubPc thin film are pretty good at 500 nm~650 nm, which matches well with the wavelength of semiconductor laser used in digital versatile disk (DVD) systems. The optical recording performance of the BTN SubPc/Al multilayer shows that high reflectivity contrast (>30%) can be obtained at lower writing power (<10 mW) and shorter writing pulse width (300 ns) by using a He Ne laser (632.8 nm) irradiation. The results demonstrate that subphthalocyanine is a promising material for short wavelength optical recording, especially used as recording medium of DVD Recordable (DVD-R).

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 8 948 (2001)
All Optical Bit Clock Extraction Technology Based on Fiber Cross Phase Modulation Effects
[in Chinese], [in Chinese], and [in Chinese]

All optical bit clock extraction technology based on fiber cross phase modulation effects is illustrated and analysed. Intensity and pulsewidth of incident signal, the length of dispersion shift fiber (DSF) and walk off between incident and clock signal influenced the output clock intensively. The relations between them are discussed and the chirp character of clock signal is analysed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 8 944 (2001)
Effect of Signal Pulse Shape on Transmission Performance of Cascaded In-Line PSA Optical Fiber Communication System
[in Chinese], and [in Chinese]

The effect of signal pulse shape on the transmission performance is studied for an optical fiber communication system with cascaded in line optical phase sensitive amplifiers (PSA′s) having phase shifting between pumping and signal light. Computer simulation shows that at different phase shifting the eye pattern degradation of high speed signal increased rapidly with the accretion of fiber dispersion, and changed with signal pulse shape for given fiber dispersion. From the simulating results, it is known that signal pulse shape also affect the system performance. The system transmission performance of using super Gaussian pulse is superior to that of using Gaussian pulse, and super Gaussian pulse has an optimum pulse exponent for best transmission performance.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 8 939 (2001)
Temporal Correction Effectiveness of Adaptive Optical System for Light Wave Atmospheric Propagation
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

By introducing the temporal correction coefficient, which is defined as the ratio between the closed loop wavefront residual error and the open loop error induced by atmospheric turbulence, and the measured signal to noise ratio, the temporal correction effectiveness of adaptive optical system for light wave atmospheric propagation is studied. Its dependence on the power law exponent of the turbulence, the cut off frequency, the measured signal to noise ratio, the time delay and the closed loop bandwidth is analyzed. The optimal closed loop bandwidth is given. The temporal compensation effectiveness of 61 element weak light adaptive optical system is also analyzed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 8 933 (2001)
Generalized Coherent States of a Non-Harmonic Oscillator in a Finite-Dimensional Hilbert Space
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Generalized coherent states of a non harmonic oscillator in a finite dimensional Hilbert space are constructed and some quantum statistical properties are studied. Their squeezing effect and antibunching effect are discussed in detail. The condition of squeezing is found, and the relation between antibunching effect and the dimensionality of the Hilbert space is shown by using numerical calculation. Theoretical calculation shows that the coherent states present squeezing effect and antibunching effect, and these quantum statistical properties are very different from those of usual generalized coherent states in infinity dimensional Hilbert space.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 8 929 (2001)
Light Squeezing in the System of Two-Mode Squeezed Vaccum Field Interacting with a Two-Level Atom
[in Chinese], [in Chinese], and [in Chinese]

The squeezing of light in the system of two mode squeezed vacuum field interacting with a two level atom within and without the rotating wave approximation by means of quantum theory is studied. The numerical results indicate that the light field is squeezed periodically. Moreover, the squeezing of light field is restrained by the virtual-photon process and relates to the initial state parameters and the properties of the system.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 8 923 (2001)
Atom-Lithography in Red Far-Detuning High-Power Standing Wave
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The focusing properties of a red far detuning high power standing wave for a thermal atomic beam are studied through numerical simulation. The result shows that this type of standing wave is possible to be used for atom lithography. The FWHM of the line width deposited on the substrate at the focal plane of the thermal atomic beam is about 20 nm, the contrast is 4~5, with beam waist w 0=0.1 mm, power P=7 W respectively. A proposal of using enhanced cavity to increase the line contrast to 7 and decrease the FWHM of the line width to 5 nm~10 nm is put forward.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 8 918 (2001)
Impulsive Stimulated Raman Scattering of Femtosecond Pulse Laser in Ferroelectrics
[in Chinese], and [in Chinese]

Impulsive stimulated Raman scattering (ISRS) was applied to some ferroelectric crystals to analyze the vibration of the crystal lattice in time domain. For significant phonon excitation to occur,the excitation pulse duration τ<2 π/ ω α. Using Ti∶Sapphire regenerative amplifier system as a light source, phono polariton oscillatory modes in LiTaO 3 could be observed. The method was applied to KH 2PO 4. Only relaxing was observed within 50 K from the ferroelectric phase transition point. The relaxation time constant τ 0 is 1.33×10 -13 s in the wave vector q=6848 cm -1 . It shows a relaxational character of the ferroelectric phase transition KH 2PO 4.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 8 913 (2001)
Coupled Wave Analysis of Anisotropic Self-Diffraction in Doped KNSBN Crystals
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Anisotropic self diffraction in doped KNSBN crystals for the anisotropic experimental configuration is studied experimently and theoretically where the c axis is perpendicular to the incident plane. The set of coupled wave equations and its numerical solutions taking the first two order space charge field into account are presented. Both theoretical analysis and experimental results show that anisotropic self diffracted light originates from the contribution of both incident beams.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 8 909 (2001)
Quantum Non-Demolition Measurement in Degenerate Three-Wave Mixing
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A quantum theoretical model for the system of degenerate three wave mixing has been established. The dynamical behavior and the features of the optical quantum non demolition (QND) measurement were studied by using nonlinear quantum optics. The results show that the efficient QND measurement can not be well performed at the operation of the nonlinear double resonances (NDR) but the nonlinear transformation of the bistability.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 8 905 (2001)
Effect of the Propagation Loss on the Cherenkov SHG in a Channel Waveguide
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Based on the coupled mode theory, second harmonic generation (SHG) in the form of Cherenkov radiation from a channel waveguide has been investigated taking the propagation loss into account. The results show that the conversion efficiency has an exponential behaviour and a saturation characteristic, which differ from the linear behaviour in the case of omitting the propagation loss. The results play an important role in the design and fabrication of Cherenkov frequency doubler.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 8 901 (2001)
ω-2ω Two-Color Phase Control of Ionization: Comparison of Tunneling and Over-the-Barrier Regimes
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

For an atom under the action of ω 2ω two color fields, the phase effects of ionization process in different ionization regimes are investigated. The dependence of ionization possibility on relative phase is found in tunneling regime being a shape of "∩", while in the over the barrier regime being a shape of "∪". Our results demonstrate the possibility of phase control of ionization process by using two color fields.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 8 897 (2001)
Absolute Scale and Spatial Distribution of Nonlinear-Optical Coefficients of GdCOB Crystal
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The whole nonlinear optical coefficients of GdCOB crystal are evaluated by phase matching SHG method and Maker fringe method. The spatial distribution of effective nonlinear coefficient d eff are proved with the crystals cut in different directions in the experiments. The results show that d eff reaches the maximum of 1.68 pm/V at the direction of θ=66.8°,φ=132.6°. The SHG conversion efficiency reaches 48% with a 6 mm long GdCOB crystal cut along this direction.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 8 1022 (2001)
High-Average-Power Self-Mode-Locked Ti:Sapphire Laser Self-Started by a Semiconductor Saturable Absorber Mirror
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A novel high power self starting mode locked Ti∶sapphire laser with a semiconductor saturable absorber mirror (SESAM) as self starting element is demonstrated. Its sloping efficiency is 22%, average power as high as 1.7 W and pulse width shorter than 16 fs. The starting dynamical process of the laser has been studied. This kind of laser will have a wide applications.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 8 1019 (2001)
Index Change of PMMA/DR1 Film During Photo-Bleaching
[in Chinese], and [in Chinese]

The photo bleaching processes in a nonlinear optical polymer film used poly (methyl methacrylate) based dispersive red one (DR1/PMMA) side chain at 488 nm argon ion laser radiation was investigated. The index change of DR1/PMMA film was measured by two beam scan technique. It provides a simple method to determinate the parameters in bleaching model describing the photo bleaching processes of polymer.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 8 1016 (2001)
Measurements of Stratosphere Aerosol with L625 Lidar
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

L625 Mie lidar and data processing for measuring stratospheric aerosol are described. The results show the good agreement with those of American NASA/SAGE Ⅱ satellite observation. Long-term variations of aerosol extinction coefficients and integrated backscatter coefficients in the stratosphere during the years of 1991~1998 are preliminarily analyzed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 8 1012 (2001)
Study on Film Attenuator of Variable Angle
[in Chinese], [in Chinese], and [in Chinese]

Theoretic analysis and numerical computation on film attenuator of variable angle are studied. The attenuator is ready to be used in SHENGUANG Ⅱ precision project. The characteristics of precisionly continuous adjust, large optical aperture, high energy loading and high beam quality are demonstrated in simulation experiment. Other optical attenuators can not provide with these characteristics solely.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 8 1008 (2001)
Diffraction Properties of Multilayer-Gratings in Soft X-Ray Region
[in Chinese], and [in Chinese]

The main diffraction properties of a soft X ray optical component--multilayer gratings are deduced and discussed in detail on the basis of X ray kinematics. Results show that main energy of diffraction light can be concentrated in one order and resolving power and reflection of multilayer grating are higher. There is essential difference between the dispersive properties of multilayer gratings and multilayers.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 8 1004 (2001)
Design and Fabrication of Antireflection Structured Surfaces
[in Chinese], [in Chinese], and [in Chinese]

On the basis of the effective medium theory (EMT), both one dimensional and two dimensional periodic structures of antireflection surface are investigated and anlyzed. The 2 D relief structure pattems for antireflection are designed and fabricated on silicon wafers by binary optical processing methods. This 2 D structure can be used as an alternative to thin film coatings to enhance transmission at the boundary between two different media.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 8 1001 (2001)
Second-Harmonic Generation in Asymmetric Coupled Zn1-xCdxSe/ZnSe Quantum Wells and Its Optical Anisotropy
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The nonlinear optical characteristics in asymmetric coupled Zn 1-x Cd x Se/ZnSe quantum wells have been investigated by using the reflective second harmonic generation (SHG) measurement technique. The SHG signal from the sample was about ten fold bigger than that from the ZnSe substrate. The photoluminescence spectra of Zn 0.70 Cd 0.30 Se quantum wells and ZnSe substrate were measured. The dependence of the SHG intensity (p in/p out, p in/s out) in the asymmetric coupled quantum wells on the azimuthal angle were studied respectively, which demonstrated the obvious nonlinear optical anisotropy.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 7 894 (2001)
Enhanced Effect of the Collisional Energy Transfer Between Na and Na2 and Diffuse Band Radiation in Na2
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The enhanced effects of the collisional energy transfer between the highly excited sodium atoms and molecules and diffuse band radiation were experimentally investigated in the sodium vapours when the buffer gas was added in. A transient collisional model was used to describe the experimental result. The theoretical analysis was in agreement with the experimental result.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 7 891 (2001)
Study of 1410 nm Wavelength Region Distributed Fiber Raman Gain Amplifier
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The operation principle of distributed fiber Raman gain amplifier is discussed. The light amplification was obtained at 1410 nm wavelength region by using a 1320 nm solid laser as pumping source and a 23 km single mode GI optical fiber. The relation between the gain of fiber Raman amplifier and the effective interaction length of optical fiber is studied. When the pump peak power is 50 W and 30 W, the effective interaction length is 15.5 km and 10.5 km. The relation between the gain of Raman amplifier and pump power at different effective interaction length of optical fiber is anlyzed. The spectrum width of Raman fiber amplifier is estimated to be 50 nm or 250 cm from the Raman backscattering spectrum of optical fiber.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 6 766 (2001)
A Study on Borate-Lead Glasses with Eu3+ Ion as Probe
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The Eu 3+ probe technique is used to the analysis of borate-lead glasses system of (79 5-x)BO 3/2 -(20+x)PbF 2-0 5Eu 2O 3(x=0,10,20,30,40). The excitation spectra for several glasses are measured, the phonon side-band spectra and electron-phonon coupling constant are obtained. The multi-phonon non-radioactive transition probabilities are discussed. The emission spectra of Eu 3+ originated from 5D 0→ 7F 0, 7F 1, 7F 2 transitions under 362 nm excitation in this glass system and the optical transitions J-O parameter Ω 2 are obtained, the structure properties of borate-lead glasses are analysed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 6 762 (2001)
Study on Sonoluminescence Imaging of Living Body
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Imaging biological tissues using sonoluminescence (SL) is a new research field developing in the latest two years. Sonoluminescence image of living body (nude mouse) was obtained by the high quantum efficiency imaging system. Fluoresceinyl Cypridina Luminescent Analog (FCLA), a chemiluminescent analytic agent, is used in vivo for the first time to enhance biological SL. An image of FCLA enhanced SL in vivo was observed too. This technique has potential application in clinics for imaging diagnosis.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 4 509 (2001)
Road Extraction by Combined Using Statistical and Structural Information
[in Chinese], and [in Chinese]

An algorithm for road extraction from a remote sensing image is presented. It contains three steps: the road elements and the road segments are firstly extracted by using multiple local statistic characteristics of the image, and the road boundaries are extracted by using energy function. Structural information is described by using statistical analysis in detecting the road elements instead of using lines extracted, to enhance the algorithm’s robustness; the parameters of energy function are determined from the result of above calculation in detecting the road boundaries to make the algorithm’s self-adaptive ability.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 4 504 (2001)
Progress of Optical Homogeneity and Weak-Absorption of Large-Sized Sapphire Crystal Used in LIGO Project
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The latest progress in the study of optical homogeneity and weak-absorption of large-sized sapphire crystal (φ113 mm×70 mm) is reported. The polishing precision of the whole crystal surface reaches 1.666λ, and the transfer wavefront distortion is 0.584λ. The transmission is higher than 80% at UV waveband and than 86% at VIS-NIR waveband. The weak-absorption coeffcient is 35×10-6 /cm~65×10-6 /cm.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 3 383 (2001)
Measurement of Converse Piezoelectric Expend and Contract of PZT with the Axial Response Curve of Fiber-Optical Confocal Scanning Imaging Microscope
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

By utilizing the axial response curve of fiber optical confocal scanning microscope, a new technique for measuring the micro position has been developed. Using this technique, the converse piezoelectric expend and contract of PZT with resolution as high as 5 nm was measured.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 3 380 (2001)
A Technique of Deformed Speciment Grating Replication for in Situ Measurement of Moire Interferometry
[in Chinese], [in Chinese], and [in Chinese]

An in situ measurement technique-deformed specimen replication has been given. The recorded information on the deformed specimen grating can be extracted by using a typical four-beam moire interferometer. Typical fringe pattern of U-field and V-field displacement contours obtained from the test. The theoretical analysis and experimental result have proved that the technique with the advantages of real time moire interferometry is suitable for a wide range of applications.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 3 376 (2001)
Two Channel Self-Focusing Matched Filter by Computer-Generated Hologram
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A two-channel matched filter using computer-generated holograph is introduced. On the basis of CGH, it can encode two objects simultaneously by adding negative quadratic phase factor on the conjugate Fourier spectrum of one object and adding positive quadratic phase factor on the Fourier spectrum of the other. The experimental results, which are consistent with theory, are given.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 2 255 (2001)
A Mirror-Dispersion-Controlled and Self-Started Femtosecond Ti∶Sapphire Laser
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A Gires-Tounois negative dispersion mirrors is designed and optimized. A mirror-dispersion controlled self-started femtosecond intercavity Ti∶sapphire laser is operated by using this mirror together with a semiconductor saturable-absorber mirror.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 2 253 (2001)
Fluorescence Characteristics of Electron Trapping Material Eu,Sm∶CaS
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The fluorescence excitation and emission spectrum of electron trapping material Eu,Sm∶CaS at room temperature are investigated. The excitation spectrum consists of four emission bands, which are assigened to 4f6→4f55d transition of Eu2+ ion and fundamental absorption of CaS. The fluorescence emission spectrum excited at visible light consists of one strongest broaden emission band and two weakest narrow emission bands. While in the spectrum excited at ultraviolet light, not only the three emission bands but also seven stronger narrow emission bands are observed, which are assigned to 4f65d→4f7 transision of Eu2+, f→f transition of Sm3+, f→f transision of Eu3+ respectively. It is found that the fluorescence emission strength of Eu2+ ion is apparent stronger than that of Sm3+ as the activator concentrations are proper.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 2 250 (2001)
High-Power Diode-Pumped Q-Switched Intracavity Frequency-Doubled Nd:YVO4 Laser
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

High power quasi CW diode laser pumped acoustic optically Q switched intracavity frequency doubled Nd:YAG and Nd:YVO 4 laser are demonstrated. Average power of 3.5 W and 3.2 W at 532 nm with a repetition rate of 22 kHz was generated respectively.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 12 1516 (2001)
Electrically Tunable DBR Laser Using Fiber Grating as External Cavity
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A novel tunable distributed Bragg reflection (DBR) laser using metal coated fiber Bragg grating as the external cavity was demonstrated. It realized single mode output with narrow line width and high side mode suppression ratio (SMSR). By tuning electrical current of the metal tube coating the fiber grating, wavelength switches among six wavelengths spanning 5 nm were achieved.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 12 1513 (2001)
Rapid Modeling of MPE Microscopic Imaging Through Turbid Medium
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A rapid and accurate model used to study microscopic imaging through turbid medium is presented which combines traditional Monte Carlo with two dimensional point spread function (PSF). The research shows that the rapid model is much faster than a pure Monte Carlo method with the help of convolution operation, when it is used to simulate multi photon excitation (MPE) fluorescence scanning microscopic imaging through turbid medium. Besides, one run instance illustrates that higher transverse resolution can be obtained in imaging through turbid medium by MPE than by confocal fluorescence microscopy.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 12 1509 (2001)
Dynamic Liquid Surface Shape Measurement
[in Chinese], and [in Chinese]

Fourier transform profilometry (FTP) is used for dynamic liquid surface shape measurement. A sequence of dynamic deformed fringe images can be grabbed by CCD camera and saved on disk rapidly. By Fourier transform, filtering, inverse Fourier transform and unwrapping these phase maps in 3 D phase space, the shape of a vortex at different times is obtained. The experimental results show that FTP can efficiently deal with the dynamic liquid surface shape measurement.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 12 1506 (2001)
A Novel Cascaded Fiber Raman Laser Operating at 1240 nm Using Fiber Loop Mirror
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A novel cascaded fiber Raman laser operating at 3rd Stokes 1240 nm using fiber loop mirror is reported. The output power at 1240 nm is 300 mW and convert efficient is about 25%, however, the properties of fiber mirror and the parameters of Raman fiber are not optimized.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 11 1407 (2001)
Effect of Plasma Density Scale Length on the Conversion Efficiency of High Order Harmonic Generation in Laser-Plasma Interaction
[in Chinese], [in Chinese], and [in Chinese]

The effect of plasma density scale length on the conversion efficiency of high order harmonic generation in the interaction of intense laser and plasma was investigated via PIC (particle in cell) simulation. The conversion efficiency of high order harmonic generation produced by the interaction between p polarized, non relativistic laser pulse and over dense plasma with different density scale lengths was calculated. The plasma density scale length significantly affects the conversion efficiency and this effect is different for different harmonic order, different laser pulse duration and different plasma density.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 11 1404 (2001)
Spectral and Laser Performance of Novel Pyrromethene-BF2 Compounds
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Six novel pyrromethene BF 2 compounds, with peak absorption wavelength in the range of 517 nm~524 nm, were synthesized. The electronic absorption spectra were measured in their solution of absolute ethanol. Pumped with a frequency doubled pulsed Nd 3+ ∶YAG laser at 532 nm, they can lase more efficiently than rhodamine 6G and show wide tunability.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 10 1278 (2001)
A Novel Method to Chirp Fiber Grating
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A novel and efficient method for chirping fiber grating is demonstrated. The fiber Bragg grating was attached slantwis on a side face of a flexible beam. When the beam is bending, a strain gradient formed along the grating produces a variable shift in the Bragg spacing, resulting in a chirp up to 11.32nm nearly without central wavelength shift.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 10 1275 (2001)
A Method of Correcting Vector Error for Resisting Light Perturbance
[in Chinese], and [in Chinese]

The precise location from the perturbanced ring image is an important step for hemispherical imaging and tracking (HIT) system targeting object. Conventional method could not satisfy the HIT system tracking object in real time. According to the feature of geometric symmetry of a circle, a new method of resisting light perturbace is presented. The experimental results show that the measurement error might be no more than 1 pixel for perturbance free images. In the meantime, by the proposed method the measurement error might be no more than 5 pixels for perturbanced images.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 10 1272 (2001)
Grating Big Shearing Digital Specle Pattern Interferometry
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A new method of big shearing digital speckle interferometry is presented. Grating is placed in image space of objective lens, and used as the shearing part. Light wave from reference object and measured object interfered at the image space. The principle of this method is discussed in detail based on Fourier optics, and plane displacement of typical specimen is measured which is a peripheral region fixed block board having symmetrical load. The results show that experimental value and theoretical value are fit well. Some applied example are given. Theory and experience are shown that this method not only have the high sensitivity of holographic interferometry (λ/4), but also have merit of low shockproof demand and in-site measurement.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 1 125 (2001)
Theoretical Analysis on Polarization Characteristics of Silicon-Based Silica Optical Waveguide Devices
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The influence of core size, relative refractive index difference, stress and bending radius of silicon-based silica waveguides on polarization was analyzed. Conclusions were drawn as below: the birefringence of square waveguide with small relative index difference is small. The birefringence caused by residual stress is larger than that by core size. Small bending radius causes high birefringence and loss, so large bending radius is preferred within the permission of chip size to reduce birefringence.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 1 122 (2001)
Remote Displacement Measurement of Solid Scattering Surface Utilizing Laser Doppler Effect
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The remote displacement measurement was realized utilizing laser Doppler effect. The Doppler shift of differential structure was analyzed theoretically. The displacement measurement system of double-beam differential acoustooptic modulating structure, large aperture collection of backward scattering light and real-time compensation of the losing signal by computer tracking software was designed. The displacement measurement of paper and metal at a distance of 10 meters was made with an accuracy of ±0.4%.

Acta Optica Sinica
Jan. 01, 1900, Vol. 21 Issue 1 118 (2001)
Refractive Index Measurement by Optical Fiber Michelson Interferometer
[in Chinese], and [in Chinese]

An improved method using white-light interferometry and optical fiber Michelson interferometer to measure group refractive index is introduced.The measurement process is simplified when sandwiched sample is used and contacted with detecting fiber surface.The collimating between sample and the detecting fiber can be adjusted according to the change of the bandwidth of the reflective peak.

Acta Optica Sinica
Jan. 01, 1900, Vol. 20 Issue 9 1294 (2000)
Narrowing and Broadening of FBG Reflection Spectra
[in Chinese], [in Chinese], and [in Chinese]

An important property of apodized weak fiber Bragg grating ;FBG is demonstrated.It shows that if the reflection spectra R;Δβ of an apodized weak FBG is needed to be narrowed to ′1/n′,i.e.from R;Δβ to R;nΔβ,then the apodizing function g;z should be broadened ′n′ times,i.e.from g;z 0<z<L to g;z/n /n,0<z<nL.Two examples are given to validate this property.

Acta Optica Sinica
Jan. 01, 1900, Vol. 20 Issue 9 1291 (2000)
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 20 Issue 8 1151 (2000)
Design of 0.35 μm Step-and-Repeat Projection Lithography Objective
[in Chinese], and [in Chinese]

The main points of design of 0.35 μm step-and-repeat projection lithography objective are introduced such as the determination of number aperture and structure model and the selection of material. The difficulties, novel design and a design result of lithography objective are discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 20 Issue 8 1148 (2000)
Relation between Contrast of Image and Imaging Range for Underwater Object
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

According to the equation which expressing the relation between the contrast of underwater image and the imaging range, and by changing the imaging rang experimentally, the figure of C-r for experimental data and the figure of C-r for theoretical calculation are compared and analysised.

Acta Optica Sinica
Jan. 01, 1900, Vol. 20 Issue 8 1145 (2000)
1342 nm Nd:YVO4 Laser End-Pumped by a Diode-Laser
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A Nd:YVO4 laser at 1342 nm end-pumped by a high power linear-array fiber-coupled diode-laser is reported. An output power of 3.22 W at 1342 nm was obtained from x=0.7 of atomic fraction Nd-doped YVO4 laser with 13.30 W of incident pump power, corresponding to a slope efficiency of 25.5%. The output power fluctuation was less than 1%.

Acta Optica Sinica
Jan. 01, 1900, Vol. 20 Issue 8 1141 (2000)
Equivalent Fresnel Numbers for Regular Polygon Aperture and Slit
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The equivalent Fresnel numbers of the regular polygon and slit are calculated by using the radius of inscribe circle and half-width of the slit as the feature length. The result can be obtained by incidence with uniform plane-wave.

Acta Optica Sinica
Jan. 01, 1900, Vol. 20 Issue 8 1137 (2000)
Experimental Study on Dispersion Compensation Transmission of Standard Single Mode Fiber
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Utilizing the cantilever beam mechanical tuning device developed by the authors both the center wavelength and the linear chirp of a 12 cm uniform fiber grating are tuned to compensate dispersion of 20 Gb/s transmission over 100 km standard single mode fiber. Experimental results show that the effect of dispersion compensation is favorable.

Acta Optica Sinica
Jan. 01, 1900, Vol. 20 Issue 8 1134 (2000)
SHG Stability of Thermally Poled SiO2-GeO2 Films
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Sol-gel method was used to prepare SiO2-GeO2 films. The relative intensity of second-harmonic generation(SHG) signals of the thermally poled films and their relaxations were measured. By comparing the decay of second-harmonic generation of the films with different substrates and under different temperatures,it is shown than the stability of charge near the interface between the film and substrate is influenced by the bulk electric resistance of the substrate,and this charge character consequently influences the SHG stability of the film.

Acta Optica Sinica
Jan. 01, 1900, Vol. 20 Issue 7 1004 (2000)
Laser Trapping of Rubidium Atoms
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The experimental result of laser trapping of rubidium atoms is reported. The frequency of a diode laser is stabilized by means of saturated absorption spectroscopy. The linewidth of laser frequency is less than 1 MHz, and the offsetting of laser frequency can be controlled freely by using acousto-optical modulator. It satisfied the requirement of laser cooling and trapping of atoms.

Acta Optica Sinica
Jan. 01, 1900, Vol. 20 Issue 6 862 (2000)
Improvement of Output Characteristics of a Large-Bore Copper Vapor Laser with Hydrogen Additive
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The effect of hydrogen additive in the Ne buffer gas on the output characteristics of a large-bore copper vapor laser has been investigated. The output power and beam spatial characteristics are significantly improved by hydrogen additive.

Acta Optica Sinica
Jan. 01, 1900, Vol. 20 Issue 6 859 (2000)
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 20 Issue 5 720 (2000)
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 20 Issue 5 717 (2000)
RF Excited Diffusively Cooled Kilowatts Carbon Monoxide Slab Waveguide Laser
[in Chinese], [in Chinese], and [in Chinese]

A RF excited diffusively cooled carbon monoxide kilowatts laser is reported.In this laser,the top electrode was cooled with the tap water and the bottom electrode was cooled with the liquid nitrogen to maintain the slab waveguide gas discharge region at a low temperature.In the experiments,a slab waveguide region was excited by a RF transverse gas discharge at a frequency of 90 MHz,a new type of optical resonator consisting of a conventional unstable resonator and a flat feedback mirror was employed.The maximum laser power output of over 1 kilowatts was obtained with a gas composition of P(CO):P(He):P(Xe):P(O2) at a ratio of 24:71:4:1.

Acta Optica Sinica
Jan. 01, 1900, Vol. 20 Issue 5 714 (2000)
Dye-Laser-Pumped Nd:YCOB Self-Frequency-Doubling Laser
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Nd:YCa4O(BO3)3,known as Nd:YCOB,is a new nonlinear multifunctional crystal.By using Datachrom-5000 dye-laser as a pumping source,a Nd:YCOB(8at%) self-frequency-doubling laser from 1.06 μm to 0.53 μm has been realized.The wavelength of the frequency-doubling laser is 530.2 nm,the lowest threshold energy is 2 mJ,the hightest conversion efficiency is 3.3%,and the highest green laser energy 1.03 mJ.The laser characteristics of Nd:YCOB self-frequency crystal are discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 20 Issue 5 711 (2000)
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 20 Issue 4 575 (2000)
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 20 Issue 4 573 (2000)
Irradiance Reconstruction for 3-Dimensional Luminous Body by Means of the Focusing Emission Computed Tomography
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The Focusing Tomography is presented to reconstruct the 3-D radiation in a luminous body. The 3-D luminous body could be considered as the combination of many 2-D parallel luminous sections. Focus on each section by only one camera, a group of images will be captured which is the overlapped image of one focused image and other defocused images. The irradiances of these images form governing equations. The irradiance distribution of different sections could be induced from above equations. In this experiment, several light emitting diodes are employed to simulate several luminous sections. Results show that this method can reconstruct the irradiance of each section.

Acta Optica Sinica
Jan. 01, 1900, Vol. 20 Issue 4 570 (2000)
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 20 Issue 3 431 (2000)
Application of Adaptive Algorithm to Evaluation of Parameters in Auroral System
[in Chinese]

The parameters in auroral system are calculated using an adaptive parametric time-domain approach. The adaptive algorithm, in which the system function is represented by a rational-form model, allows on-line real-time application. The data processing illustrates that the effective mean lifetime of O(1S) thus determined, resulted from the [OI32] transition of atomic oxygen, is in accordance very well with the one evaluated in frequency-domain.

Acta Optica Sinica
Jan. 01, 1900, Vol. 20 Issue 3 428 (2000)
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 20 Issue 2 288 (2000)
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 20 Issue 2 286 (2000)
Experiments of Real-Time Atomspheric Turbulence Compensation with Phase Conjugation of Limited Beams
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The effects of the sampling aperture sizes on the phase conjugation correcting atmospheric turbulence along a horizontal path of 1000 m and 4 m above ground are reported. The results show that the corrected effects and peak energies are related to the sampling aperture sizes, and there is an optimum sampling aperture for a given system.

Acta Optica Sinica
Jan. 01, 1900, Vol. 20 Issue 2 283 (2000)
Conic Scanning of Biaxial Crystal
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The conical refraction effect of biaxial crystal is studied deeply. Dynamic conic refraction of any conical angle within the range of 0~25° is obtained using KNbO 3 crystal with a single pin hole aperture. The principles of conical refractional scanning (CRS) and a novel laser CRS instrument are developed. Spatial CRS within modulated conical angle is realized.

Acta Optica Sinica
Jan. 01, 1900, Vol. 20 Issue 12 1704 (2000)
Modulation Instability in Decreasing Dispersion Fibers
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Modulation instability in decreasing dispersion fibers (DDF) is investigated by means of theoretical analysis and numerical simulation. The gain spectrum of modulation instability is obtained as a function of axially-varying dispersion parameter. The results show that the gain spectrum of DDF is much broader than that of ordinary optical fibers. The broad gain bandwidth can be obtained by selecting the dispersion parameter of DDF. The numerical simulation also shows that fundamental soliton pulses with high repetition rate can be generated in this kind of fiber by modulation instability.

Acta Optica Sinica
Jan. 01, 1900, Vol. 20 Issue 10 1435 (2000)
Discussion on Phase Errors Caused by Frequency Leakage in FTP
[in Chinese], [in Chinese], and [in Chinese]

The phase error caused by leakage in a 3-D object measurement Fourier transform profilometry (FTP) method is discussed. Because the deformed fringe pattern captured by CCD camera is a function with limited extension in space, it must be extended to infinite space before discrete Fourier transform is computed. If the extended period is not integer times of the grating period, the smooth fringes can not be obtained through extending. When Fourier transform of the discontinuous fringe is calculated, phase error will occur, which is called leakage error. In this paper, the relationship between extended period and frequency leakage is analyzed, the calculation model of phase errors caused by leakage is proposed, quantitative analysis of phase error is presented. A fringe extrapolation method is put forward to decrease the leakage errors. Computer simulations and primary experiments have confirmed the analysis.

Acta Optica Sinica
Jan. 01, 1900, Vol. 20 Issue 10 1429 (2000)
A Wavelength-Selective Switch Based on Fiber Bragg Grating and Fiber Loop Mirror
[in Chinese], [in Chinese], and [in Chinese]

A new structure optical wavelength-selective switch based on fiber loop mirror and fiber Bragg grating is studied. The dynamic range of greater than 17 dB and insertion loss of 0.5 dB at wavelength-selective port were obtained. The measured spectra and numerical simulation indicate that the imperfect of the device can be attributed to the definite difference between the two arms, which was about 1.35 mm. Devices with better characteristics can be developed by decreasing the difference.

Acta Optica Sinica
Jan. 01, 1900, Vol. 20 Issue 10 1425 (2000)
Soft X-Ray Microscopy of Wet Samples in Helium Environment
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Soft X rays of “water window” waveband is very beneficial to the study of hydrated biological materials. The theoretical basis, experimental setup, experimental results and its significance of the soft X ray microimaging in helium environment are described. The study is made at Soft X ray Microscopy Station, NSRL.

Acta Optica Sinica
Jan. 01, 1900, Vol. 20 Issue 1 142 (2000)
Green Thin Film Electroluminescent Devices Using Ceramic Thick Film as Insulator Layer
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A green thin film electroluminescent device using ceramic thick film as insulating layer has been manufactured. The transparent layer is ZnO doped with Al made by sputtering and the luminescent layer is ZnS:Er, Cl made by electron beam evaporation method. The dependence of brightness on voltage was measured as well as the dependence of efficiency on voltage.

Acta Optica Sinica
Jan. 01, 1900, Vol. 20 Issue 1 139 (2000)
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 19 Issue 9 1296 (1999)
Soft X-Ray Images of Hydrated Biological Samples in a Vacuum
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A simple and practicable method was adopted to image the biological samples, plant leaf epidermal cells after being fixed, using soft X-rays in a vacuum environment. The micrographs of their cells were acquired in the experiment. Compared with the image method in air, this method has some advantages such as exposure time decreasing and operation safe.

Acta Optica Sinica
Jan. 01, 1900, Vol. 19 Issue 8 1150 (1999)
Spectroscopic Characteristics of Cr3+ Doped Glass-Ceramics
[in Chinese], [in Chinese], and [in Chinese]

Transparent glass-ceramics doped by Cr3+ was prepared by the process of phase separation and the raw materials of analytical reagents in the system of B2O3-Al2O3-SiO2. The absorption and emission spectra of glass and glass-ceramics were measured respectively. The spectroscopic characteristics were studied.

Acta Optica Sinica
Jan. 01, 1900, Vol. 19 Issue 8 1146 (1999)
Digital Measurements and Fabrication of Low loss Optical Organic Polymer Waveguides
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The techniques of fabricating low loss optical organic polymer waveguides are demonstrated. A new methodCCD camera photographing methodis applied to detect the propagation loss in the waveguide. The samples with propagation losses less than 0.5 dB/cm at 632.8 nm are fabricated experimently.

Acta Optica Sinica
Jan. 01, 1900, Vol. 19 Issue 8 1142 (1999)
Light Scattering Measurement of Surface Roughness by Variable Wave Vectors
[in Chinese], [in Chinese], and [in Chinese]

Based on the linear relationship between the logarithm of the central peak energy and k2⊥ in light scattering, a method for the measurement of surface roughness by changing the wave vectors is proposed. Experimental measurements of 6 samples of silicon backsides were conducted

Acta Optica Sinica
Jan. 01, 1900, Vol. 19 Issue 7 1006 (1999)
Polarization-Controlled Photorefractive Switch
[in Chinese], and [in Chinese]

Two modes polarization-controlled photorefractive switches are proposed. Analytical equation of the diffraction efficiency ratio on readout with extraordinarily polarized and ordinarily polarized beams is deduced. It is demonstrated that the diffraction efficiency of the photorefractive hologram is relevant to the polarization of the readout beams, and this diffraction efficiency ratio can range from 80%~90%, this property can be used to implement the switches.

Acta Optica Sinica
Jan. 01, 1900, Vol. 19 Issue 7 1003 (1999)
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 19 Issue 6 863 (1999)
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 19 Issue 6 862 (1999)
A Novel Polymer Laser Dye
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The stimulated emission properties of a new synthesized polymer dye were reported

Acta Optica Sinica
Jan. 01, 1900, Vol. 19 Issue 6 860 (1999)
Practice of Optimization End-Fire Couplingin Optical Waveguide Loss Measurement
[in Chinese], and [in Chinese]

The problems in application of the optimum end-fire coupling techniques such as system loss determination and optical path adjustment are discussed. By using the determination method with standard, visible light assistant and optical-electrical detection for adjusting the whole reflection mirror, the satisfactory results are obtained.

Acta Optica Sinica
Jan. 01, 1900, Vol. 19 Issue 5 718 (1999)
Convex Cylindrical Lens Array Line Focusing System
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The principle and configuration of the cylindrical lens array (CLA) line focus system are described. The causes of damage of aspherical lens in aspherical lens in the concave CLA are analyzed. The design principle and performances of the CLA and its operation are introduced.

Acta Optica Sinica
Jan. 01, 1900, Vol. 19 Issue 5 713 (1999)
A Novel Fabrication Technique of Long Period Fiber Gratings
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A Novel fabrication technique of long-period fiber gratings is proposed, which are fabricated with periodic modulation of the refractive index of the core by heating and tapering fiber with carved periodic V-grooves. The experimental results are presented, and their fundamental principle is analysed. The most common use of the long-period fiber gratings is as a broadband rejection filter for WDM systems.

Acta Optica Sinica
Jan. 01, 1900, Vol. 19 Issue 5 709 (1999)
Sol-Gel Derived Self-Sustained Film by Adopting Organic-Inorganic Composite Alkoxide as Precursors
[in Chinese], [in Chinese], and [in Chinese]

A large size self-sustained film with considerable thickness ranging from 30 μm to 500 μm was prepared through sol-gel method by adopting dimethyldiethoxysilane/tetraethoxysilane composite material as precursors. The film exhibits satisfactory plasticity and film forming capability as well. AFM (Atomic Force Microscope) investigation of the film surface showes a mean roughness of 0.3 nm. Gas chromatogram/mass spectrum analysis indicates that a large amount of [(CH3)2Si-O]n molecules were formed during the hydrolysis and condensation processes. These molecules act as space filler within the gel network. Such filler not only leads to the structural flexibility and plasticity of the film, but also inducess the substantial decrease of the capillary forces and shrinkage in the film.

Acta Optica Sinica
Jan. 01, 1900, Vol. 19 Issue 4 574 (1999)
Absorption and Dispersion of Visible Light in CoPc Thin Film
[in Chinese], and [in Chinese]

The refractive index, absorption index and absorption spectra on a cobalt phthalocyanine (CoPc) thin film are theoretically calculated. The theoretical resultis is in a good accordance with the measured data. The theoretical formulas about optical absorption and dispersion changing with frequency in dielectric are analized.

Acta Optica Sinica
Jan. 01, 1900, Vol. 19 Issue 4 570 (1999)
Fluorescence Phase-Sensitive Imaging with Beam Scanning
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Employing computer to control optical scanners and lock-in amplifier to modulate gain and shift phase, a fluorescence phase-sensitive imaging system has been investigated for ruby and Ti-sapphire experimentally. The images with phase shift of π/12, π/4, and 7π/12 were obtained. The time resolution and the space resolution, as well as the practicality, of the system are analyzed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 19 Issue 4 567 (1999)
The Theoretical Analysis and Experimental Simulation of Astigmatic Elliptic Gaussian Beam
[in Chinese], [in Chinese], and [in Chinese]

A method for dealing with a kind of elliptical Gaussian beam which has simple astigmatic character is discussed, and two across cylindrical lens are used to imitate a spherical biaxial lens on transforming the beam from a semiconductor laser. A fairly perfect result is obtained that elliptical Gaussian beam is transformed into an approximately similar circular Gaussian beam.

Acta Optica Sinica
Jan. 01, 1900, Vol. 19 Issue 3 428 (1999)
Laser-Produced X-Ray Source by Using Microcapillary Target
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A new experiment was carried out for studying the interaction of high intensity laser with microcapillaries by using an ultra-short high intensity laser with 45 fs pulse width. X-ray spectra of stainless steel microcapillary and glass microcapillary are obtained successfully. An X-ray source with good direction and 10 Hz repetition rate is created.

Acta Optica Sinica
Jan. 01, 1900, Vol. 19 Issue 3 425 (1999)
Slowing Down in Optical Tristability Systems
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Two kinks of the slowing down in the optical tristability systems are studied. One is the critical slowing down at the edges of tristable region and the bifurcation, and their critical exponent is calculated; the other is the slowing down far from the critical point, which is concerned with the unstable steady points. The results show universal properties.

Acta Optica Sinica
Jan. 01, 1900, Vol. 19 Issue 2 283 (1999)
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 19 Issue 12 1709 (1999)
Red Electroluminesence Europium Polymer Complex
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The Eu3+-containing polymer ternary complex was synthesized. And it was used as the emitting layer of the organic electroluminesence (OEL) device successfully. The red light of Eu3+ from the electrominesence (EL) device was seen at 16 V. A considerable difference between the EL and photoluminesence (PL) spectra was observed. It was noticed that two spectra were very different. In PL spectrum the main peak was at 618 nm. But for the OEL spectrum, there are two peaks at 595 nm and 657 nm. The probable mechanism was discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 19 Issue 12 1705 (1999)
A Device for Testing Spectral Responsivity of Semiconductor Photodetector
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The testing of spectral responsivity of semiconductor photo detector is discussed. A device used for testing spectral responsivity with wavelength ranged from 0.4~1.1 μm is developed. It can be used to test relative spectral responsivity, absolute spectral responsivity and quantum efficiency, and the effect of instability of source can be eliminated. The testing results are compared.

Acta Optica Sinica
Jan. 01, 1900, Vol. 19 Issue 11 1581 (1999)
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 19 Issue 10 1439 (1999)
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 19 Issue 10 1437 (1999)
Needle Method and Initial Coating Design
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The initial coating design in the coating optimization is discussed, especially, the initial design in Needle method and an amelioration of Needle method is presented. It begins from the same thickness of single layer to work out the optimum design in the way of automatically revising the initial thickness by controlling the value of the merit function.

Acta Optica Sinica
Jan. 01, 1900, Vol. 19 Issue 10 1433 (1999)
Intracavity Frequency Doubling Effects in Different Picosecond Unstable Resonators with KTP Crystal
[in Chinese], and [in Chinese]

By using KTP crystal as intracavity frequency doubling generator of a mode-locked Nd:YAP laser, efficient SHG in colliding pulse mode-locked (CPM) unstable resonator with antiresonant ring (ARR) and confocal unstable resonator has been demonstrated. The energy conversion efficiencies are 53.4% and 60.2%, pulse durations in fundamental wave are 8 ps and 18 ps, and the maximum energy fluctuation in second harmonic wave are 10.6% and 12.5%, respectively. The characteristics in both resonators and their experimental results are theoretically analyzed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 19 Issue 1 141 (1999)
Femtosecond Optical Pulse Characterization with Blue Light Emitting Diodes
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The characterization of femtosecond optical pulses for Ti:sapphire laser output is conducted with two photon induced transitions in blue light emitting diodes. Excellent phase relationship between the two separated pulses are recorded from the fringes of the two photon induced, second order correlation function. It is demonstrated that the two-photon induced current can greatly simplify the femtosecond pulse characterization by direct converting the photon signal to current signal.

Acta Optica Sinica
Jan. 01, 1900, Vol. 18 Issue 9 1278 (1998)
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 18 Issue 8 1152 (1998)
Study of SrS (Eu,Sm) Electron-Trapping Thin Film Used in Optical Storage and Information Processing
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The properties of SrS(Eu, Sm) electron-trapping thin film grown by elctron beam evaporation are studied. The X-ray diffraction pattern, microstructure measuered by atomic force microscopy, optical spectra and the stored image are presented. The results show that the electron-trapping thin film has good optical properties and can be used in optical storage and information processing.

Acta Optica Sinica
Jan. 01, 1900, Vol. 18 Issue 8 1149 (1998)
Design and Imaging Analysis of Integrated Flat-Field Grating with Stigmatic Points
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A general method for the design of a two-dimensional concave grating with stigmatic points is presented. The construction of gratings with three stigmatic points is given. The image quality versus the dispersion and the grating width are analyzed in detail.

Acta Optica Sinica
Jan. 01, 1900, Vol. 18 Issue 8 1145 (1998)
Fitting Expression of the Birefringence Phase Retardation and Its Use
[in Chinese], and [in Chinese]

The phase retardation expression of ordinary and the extraordinary light in birefringence crystal is discussed.The common used expression is expanded a suitable fitting expression and the relations between its coefficient and the birefringence index are obtained. The use of the fitting expression is given. It can be a principle for designing liquid crystal and the pretilt angle tester using the method of crystal rotation.

Acta Optica Sinica
Jan. 01, 1900, Vol. 18 Issue 8 1141 (1998)
Binary Phase Corrector for Phased Array System
[in Chinese], and [in Chinese]

We present a novel method for phase correction by using binary optical elements (BOEs). This method considerably simplifies the structure of the system and decreases its size and weight. This is a typical application of binary optics in modern optical system. In the phased array system, we use binary phase corrector to correct the residual wavefront aberrations. The BOE has eight steps. The experimental result shows that this element decteased the wavefront aberrations to half of the original value.

Acta Optica Sinica
Jan. 01, 1900, Vol. 18 Issue 8 1138 (1998)
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 18 Issue 7 960 (1998)
Stabilizing Actively Mode-Locked Fiber Ring Laser By Suppressing the Phase Noise
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Cavity length shift is the main reason that causes the instability of an actively mode-locked fiber ring laser. We derived the relation between the phase noise of output pulses and the cavity length shift. By suppressing the phase noise, we made the actively mode-locked fiber ring laser operation stably for more than 8 hours.

Acta Optica Sinica
Jan. 01, 1900, Vol. 18 Issue 7 956 (1998)
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 18 Issue 6 832 (1998)
Relation between Dispersion and Reflective Response in Gratings and Its Application
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The electronic and magnetic field in a grating is a Hamiltonian system. Its conserved quantities are used to get the relation between the dispersion and the reflective coefficient. This is helpful for the analysis of spectral characteristics of the gratings.

Acta Optica Sinica
Jan. 01, 1900, Vol. 18 Issue 4 510 (1998)
Er3+Doped Fiber Laser with All Fiber Dispersive Cavity

Some experimental results on Er 3+ doped fiber laser pumped by a 971 nm semiconductor laser are reported. A fiber laser with all fiber dispersive cavity formed by a fiber loop reflector and a fiber grating is proposed and successfully demonstrated. Laser output with linewidth narrower than 0.05 nm at 1.55 μm waveband is obtained.

Acta Optica Sinica
Jan. 01, 1900, Vol. 18 Issue 4 507 (1998)
A Distributed Interference Fiber-Optic Sensor System for Long Distance Measurement
[in Chinese], [in Chinese], and [in Chinese]

A novel distributed interference fiber optic sensor system for long distance measurement is proposed based on Machelson interferometer using a modulated laser (Frequency modulated continuous wave). By incorporating an optical loop with a frequency shifter in the reference optical path of Machelson interferometer, the measurement range of the sensor system has been increased 4 times and reached 48 meters.

Acta Optica Sinica
Jan. 01, 1900, Vol. 18 Issue 2 253 (1998)
Photodetachment of the Negative Cabon Ion (2s22p3) and (2s12p4)
[in Chinese], and [in Chinese]

Electron electron correlation is more significant in negative ions than neutral atoms, often dominating the atomic structure of the ion and the cross section for interaction with an extrenal field. The negative carbon ion (2s 22p 3) and (2s 12p 4) levels, wavelength, radiative lifetime and photodetachment are discussed. The double states (1s 22s 12p 4) of negative carbon ion are more steady than its quartet states. The wavelength between (2s 22p 3) and (2s 12p 4) is located near XUV and 6 strong wavelengths are given. It can offer material for X ray laser.

Acta Optica Sinica
Jan. 01, 1900, Vol. 18 Issue 2 250 (1998)
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 18 Issue 12 1770 (1998)
Analyzing the Inverse Problem of the Multipass Laser Amplifier System Containing a Spatial Filter by Using Successive Iteration Method
[in Chinese], and [in Chinese]

Based on the Frantz Nodvik equation and Huygens Fresnel diffraction integral, an successive iteration method has been presented to solve the inverse problem of a multipass laser amplifier system containing a spatial filter. Numerical caculations have been performed. The numerical calculatior method and results obtained can be used to design high power multipass laser amplifiers.

Acta Optica Sinica
Jan. 01, 1900, Vol. 18 Issue 12 1765 (1998)
Novel Method for Writing Long-Period Fiber Grating in Single-Mode Fiber Using Micro-Lens Array
[in Chinese], [in Chinese], and [in Chinese]

An efficient method to write long period fiber grating using a micro lens array is reported. It is possible to using several hundred excimer laser pulses to write a long period grating by using this method.

Acta Optica Sinica
Jan. 01, 1900, Vol. 18 Issue 11 1599 (1998)
Chirped Fiber Bragg Grating Dispersion Compensation
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Dispersion compensation experimental result on 103 km long standard fiber link is presented. The chirped fiber Bragg grating used in our experiment is obtained by chirping a 10 cm long uniform grating into a chirped one.

Acta Optica Sinica
Jan. 01, 1900, Vol. 18 Issue 11 1597 (1998)
Numerical Simulation of Propagation of Diffuse Reflection Light of Extended Object
[in Chinese], and [in Chinese]

The propagation of diffuse reflection light of an extended object is numerically simulated. It is shown that propagation and imaging of the paraxial diffuse reflecting light near optical axis of the receiving telescope can be calculated by the paraxial scalar wave equation and phase screen algorithm. The turbulent effects on the image propagation are calculated and discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 18 Issue 10 1470 (1998)
Obtaining Hollow Beam Using Dislocation Grating
[in Chinese], [in Chinese], and [in Chinese]

The interference pattern between a screw wave and a plane wave is investigated and the diffraction gratings were synthesized with the aid of a computer. Using the synthesized gratings with different orders, hollow beam of different sizes is obtained.

Acta Optica Sinica
Jan. 01, 1900, Vol. 18 Issue 10 1467 (1998)
Measurement of Dynamic Parameters of the Excited States (21Π0) in Na2
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

By means of two photon resonant three photon ionization spectroscopic technique, ionization spectrum of X 1Σ + g→2 1Π g of the sodium dimer in range of ( 16574.5~16590.5 ) cm -1 was detected and its three resonant ionization features were identified. With the measurement of ion current decay curves of the three features, dynamic parameters of them were obtained.

Acta Optica Sinica
Jan. 01, 1900, Vol. 18 Issue 10 1464 (1998)
Absorption Increasing Optical Bistability Using Er-Doped Fiber
[in Chinese], [in Chinese], and [in Chinese]

The observation of increasing absorption nonlinearity and bistability without cavity in Er doped fiber is reported. The operation power is low (submillilatts). The mechanism of Er doped fiber in creasing absortion optical bistability is analysed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 18 Issue 10 1459 (1998)
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 17 Issue 7 960 (1997)
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 17 Issue 7 959 (1997)
Coherent Soft X-Ray Radiation Obtained by High-Order Harmonic Generation
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

With 45 fs 2 TW Ti:sapphire laser system, the effects of laser intensity and gas density on the high order harmonic generation were studied. The highest order harmonic up to the 25 th(31.4 nm) in argon was observed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 17 Issue 7 957 (1997)
Ultraviolet Oscilloscope Paper Used in Array Camera to Record the Far Field of Laser Beam
[in Chinese], [in Chinese], and [in Chinese]

For recording the far field of 1.06 μm wavelength laser beam with an array camera, and using film to record the array spot diameter, it is difficult to read the spots diameter exactly and also affected by the developing condition. However, there are no such problems if the ultraviolet oscilloscope (UO) paper is used instead of the film. Using the UO paper to record the array spot diameter, the measured beam divergence (at 70% energy) fluctuation is less than 10%, and the energy (at mean divergence) fluctuation is within 5%.

Acta Optica Sinica
Jan. 01, 1900, Vol. 17 Issue 6 831 (1997)
Design of Optical System for New CCD Microscopic Objective
[in Chinese]

New CCD refracting objective of a short tube length with a long working distance on microscope is suggested and analyzed in detail. Data and results of optical design on this objective are given.

Acta Optica Sinica
Jan. 01, 1900, Vol. 17 Issue 6 828 (1997)
An Experimental Method for the High Resolution Investigation of External Field Effects of Rydberg Atoms
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

An experimental method for the high resolution investigation of external field effects of Rydberg atoms is proposed. From the preliminary results of Rydberg Cs atoms in various external fields obtained by this method, the potential of the method for the external field effect studies of Rydberg atoms has been demonstrated.

Acta Optica Sinica
Jan. 01, 1900, Vol. 17 Issue 6 824 (1997)
Approximate Expressions for Intensity of the Phase-Conjugate Wave in Photorefractive Media
[in Chinese]

Based on an exact solution of nonlinear coupled wave differential equations for photorefractive media, a conservative quantity which plays an important role in the process of deriving the exact solution is discussed. By elementary transformantions, several approximate expressions for intensity of the phase conjugate wave under different special conditions are obtained. As compared with other approximation methods reported, this approximation method is no need of establishing and finding solutions of reduced differential equations, therefore it is characterized by general suitability and simplicity.

Acta Optica Sinica
Jan. 01, 1900, Vol. 17 Issue 6 820 (1997)
Temperature Induced Quenching of the Raman Scattering on CdTe Crystal Surface
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The relationship of the Raman scattering signal intensity on the CdTe crystal surface and the exciting laser power was studied using the Fourier transform Raman scattering technique. The experiment results are analysed and interpreted.

Acta Optica Sinica
Jan. 01, 1900, Vol. 17 Issue 3 382 (1997)
Wavelength Conversion Using a Light-Injection DBR Laser Diode at 2.5 Gbit/s
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The experimental results of the wavelength conversion by employing a light injection DBR laser diode at 2.5 Gb/s are presented, which can be used in optical communications.

Acta Optica Sinica
Jan. 01, 1900, Vol. 17 Issue 12 1770 (1997)
In-Line Soft X-Ray Holographic Image and Digital Reconstruction at "Water Window" Wavelength Region
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

X-ray Gabor in line holograms of wire-like object is recorded in photoresist. After enlarged to film by microscope and digitized by scanning microdensitometer, the holograms are reconstructed by using numerical methods, and the origin objects can be clearly observed in the image plane. The 3.2 nm soft X rays used in experiments are the bending magnet radiation of a 800 MeV electron storage ring and have been monochromatized by linear monochromator. The estimated resolution of the reconstructed images are better than 2 micrometers and remains to be improved in the future.

Acta Optica Sinica
Jan. 01, 1900, Vol. 17 Issue 11 1599 (1997)
Ablation Characteristics of Diamond Film by Nd:YAG Laser
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Dimond film was cut by a Nd:YAG laser and the ablation rate and characteristics were studied. An ideal condition of ablation for dimaond film was discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 17 Issue 10 1468 (1997)
Laser Characteristics of Nd:S-FAP Crystal at 1.328 μm
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The performance of low-threshold and high-efficiency Nd:S-FAP laser at 1.328 μm has been realized by using xenon flash lamp and tunable dye-laser (570~600 nm) pump respectively. The centre wavelength of frequeney-doubling laser is 664 nm and the linewidth is 1.3 nm. When the transmission of output reflector is 7%,for xenon flame pump the threshold energy is 240 mJ and the slope effeieney is 0.85%, while for tunable dye-laser pump, the threshold energy is 4.5 mJ and the slope efficiency is 38%. The laser characteristics, such as the emission spectrum, the polarization, the devergenee angle and the output energy in different cavity length were given.

Acta Optica Sinica
Jan. 01, 1900, Vol. 17 Issue 10 1466 (1997)
Subfringe Integration Profilometry for the Measurement of 3-D Object Shapes
[in Chinese], [in Chinese], and [in Chinese]

A new technique of fringe analysis is proposed to measure the 3-D objest shape. A grating pattern is projected onto an object,and the grating pattern deforms in accordance with the 3一object shape. T his deformed grating image is analyzed by means of subfringe integration algorithm·T he phase distribution and profile of the object shape are given.

Acta Optica Sinica
Jan. 01, 1900, Vol. 17 Issue 10 1462 (1997)
Corrected Calculation of Narcissus Induced Temperature Difference in Scanned Infrared Imaging Systems
[in Chinese]

Based on the principles of radiometry and consideration of receiving size of the detector, the method now being used to calculate narcissus induced temperature difference is corrected. It can be used to evaluate the narcissus effects during optical design process and also to provide narcissus criteria for thermal imaging systems.

Acta Optica Sinica
Jan. 01, 1900, Vol. 17 Issue 1 126 (1997)
A Design of Femtosecond Pulse Stretcher
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A kind of compact and effective femtosecond pulse stretcher are designed reasonablely based on the Kirchhoff Fresnel integral. Not only a high stretching rate has been obtained, but also the spatial characteristics of the light beam through the stretcher has been reconstructed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 17 Issue 1 122 (1997)
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 9 1344 (1996)
A Soliton Solution for Laser Pulse and Wake Field of Intense Laser Plasma interaction
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A 1D soliton solution for laser pulse and wake field of intense lase plasma interaction is given in the condition of weak relativistic. The thin plasma is assumed being homogeneous.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 9 1341 (1996)
Study on Property and Formation of He+Ions Implanted LiNbO3Waveguide
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Fabrication of LiNbO 3 crystal waveguides implanted by He + ions is reported in this paper. The effective refractive index of the guided modes were measured before and after annealing. The refractive index profiles were calculated and proved to be in agreement with the damage profile and range profile.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 8 1215 (1996)
Adjustable Transmission Property of Electrorheological Fluid
[in Chinese], and [in Chinese]

Measurements have been made of He Ne laser transmission through suspensions of SiO 2 in silicone oil. When electrostatic fields were applied paralled to the laser path, transmission could be adjusted through selecting proper electrostatic field and suspension concentration. While electrostatic fields were applied perpendicular to the laser path, transmission declined quikly and then recovered slow, but no initial decline was observed for high concentration suspensions.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 8 1211 (1996)
Application of a Five Aperture Shearing Camera in Measurement of Second Order Derivatives
[in Chinese], [in Chinese], and [in Chinese]

In this paper, the five aperture shearing camera used for measuring second order derivatives of objects is presented. The pure second order derivatives of objects can be obtained by using the double whole field filtering technique.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 8 1208 (1996)
Design and Prepartion of Architecture Energy Conserving Coatings
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The design of architecture energy conserving coatings with the metal double layers and the tripe layers is presented. A detailed discussion involves the design parameters as well as the transmittance and the reflectance properties. Uniformity of thicknesses of large area coatings is simulated by a computer and optimized distribution of evaporation sources is given. Experiments show that acceptable uniformity can be reached by using computer simulated distribution of evaporation sources. The measured spectral properties of such coating are presented.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 8 1204 (1996)
A CW Nd:YAG Laser of Single Frequency and Single Mode at 1.3188 μm
[in Chinese], [in Chinese], and [in Chinese]

A CW Nd3+:YAG laser of single frequency and single mode at 1.3188 μm is diveloped. The laser threshold, direction, stability, laser spectra and laser output power are measured. The results were analysised by optical theory.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 8 1201 (1996)
Edge Enhancement of Binary Image Using Step filter
[in Chinese]

This paper deals with a optical method of edge enhancement of the binary image using the step filter. Properly shifting the filter on the frequency region can improve the contrast and the contour acuity of the output image. It is profitable for edge detection.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 8 1197 (1996)
Microlens Array Fabrication by Using Laser Direct Lithography System
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

In the paper, the method for fabrication of diffractive microlens array using laser direct lithography system and reactive etching machine is described. The diffractive efficiency and the fabricating errors are analyzed. The microlens array has been used in a minature Shack Hartmann wavefront sensor.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 8 1194 (1996)
Self-Starting,Stable Ultrashort-Pulsed Ti:Sapphire Laser with Low Pump Power
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Self-starting, stable ultrashort-pulsed Ti:sapphire laser with low pump power was demonstrated without additional materials or slit. The laser produced stable pulses of24. 6 fs. A bandwidth of 53 nm was observed which would correspond sub- 13 fsaccording ideal value of 0. 315 for time-bandwidth product.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 7 1023 (1996)
A Ti:Sapphire Laser Pumped Neodymium-Doped Tellurite Glass Laser
[in Chinese], [in Chinese], and [in Chinese]

A Ti:Sapphire laser purnped bulk Nd3+ doped tellurite glass laser operating at 1066 nm is demonstrated. The lasing threshold of 4. 20 mJ and slope efficiency outputenergy versus-pump energy of 14. 7 % were observed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 7 1020 (1996)
Mode Cutoff of Multiple Quantum Well Optical Waveguides
[in Chinese], [in Chinese], and [in Chinese]

The mode cutoff equation of the multiple quantum well optical waveguidescomposed of two materials is derived. The cutoff characteristic of the strained Ge.Si1-x/Simultiple quantum well optical waveguides grown on Si substrate is analyzed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 7 1017 (1996)
Light Emission in a Dye Solution with Scatterers
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

When a suspension of dye with strongly scattering media is excited, the emission exhibits a property of norrow spectral bandwidth. This effect depends on the gain length in the suspension. The multiple elastic scattering of photon can effectively enhance the gain length.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 6 893 (1996)
CC-Banyan Network and Its Optical Implementation
[in Chinese], [in Chinese], and [in Chinese]

Optical CC-banyan network has been implemented by using polarizing beam splitters and 1-D phase spatial light modulators, and the routing control between any input-output pair is given. Its corresponding energy loss and crosstulk are low, and its channel density is high. It is compact in structure and effective in performance.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 6 889 (1996)
Study on the Aberration of a Resonator for Self-Mode-Locked Ti:Sapphire Laser
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The aberration of a resonator for self-mode-locked Ti:sapphire laser is studied. The influence of the coma to the X-shape and Z-shaPe cavity is analyzed. The advantage of the X-shape cavity is indicated in comperison with Z-shape cavity. As short as 19 fs pulses have been obtained from this laser with average power of 320 mW and bandwidth of 42 nm at center wavelength of 784 nm.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 6 885 (1996)
Surface-Enhanced Energy Transfer Effect Between Molecules
[in Chinese], [in Chinese], and [in Chinese]

Energy transfer effect between molecules adsorbed on rough silver surface has been studied by means of fluorescence spectroscopy. Enanced acceptor fluorescence and quenched donor fluorescence have been observed experimentally. On the basis of surface local electromagnetic theory, it is found that the non- radiative energy transfer rate between molecules adsorbed on silver surface is enhanced by two orders of magnitude when the molecular frequencies lie on the vicinity of resonance frequency of surface plasma. The results provide evidence for surface-enhanced energy transfer effect between molecules.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 6 881 (1996)
RF Excited Diffusively Cooled Packed Slab Waveguide Kilowatt CO2Laser
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A new type of packed slab waveguide CO2 laser is demostrated, with which over 1 kilowatt power output is obtained from an only 500 mm electrode length device. This technique is possible to obtain multikilowatts power output compact CO2 lasers.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 6 877 (1996)
Direct Writing of Bragg Reflecting Gratings in Optical Fibers by Ultravoilet Light
[in Chinese], [in Chinese], and [in Chinese]

Direct writing of fiber Bragg gratings (FBG) by an excimer laser using phase mask copy method is reported. FBGs written in B Ge co doped single mode silica fibers with Bragg wavelength of 1541.80 nm, bandpass of 0.2 nm and central reflectivity of 95% have been observed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 5 703 (1996)
Laser Chracteristics of Xenon Flash Lamp Pumped Nd:S FAP Crystal
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The absorption spectrum of a new crystal Nd:S FAP was measured and a broad effective absorption band and two strong absorption pesks at 575 nm and 804.5 nm were observed. By using a Xeon flash lamp pumping, laser operation has been demonstrated at 1.059 μm with threshold energy of only 150 mJ, slope efficiency of 1.25% and a peak power of 10 MW/cm 2. The emission spectrum, output energy and pulse width were presented. The prospect of Nd:S FAP crystal for low threshold and high efficiency miniature laser was discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 5 700 (1996)
A High Quality Hollow Metallic Optical Waveguide
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Properties of an optical quality circular metallic hollow waveguide are discussed and the technique for fabricating such a waveguide is decribed. The waveguide with gold or silver as the waveguide cladding material exhibits the characteristics of low propagation loss, transmission insensative to waveguide bending and misalignment, and capability of transmitting high power light from visible to far infrared. It is demonstrated that transmission of He Ne laser is independent of the refractive index of the liquid filled into a gold hollow waveguide, and this characteristic greatly extends the nonlinear waveguide applications. The mechanism for a “hollow fiber” in the 10.6 μm spectral region is discussed and results of propagation of CO2 laser through a gold hollow waveguide are presented.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 5 696 (1996)
1.3 μm Distributed Feedback Diode Laser Module
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A kind of distributed feedback (DFB) diode laser module was developed for the use of Amplitude Modulation Cable Television (AMCATV) transmitter. The module is an InGaAsP/InP Double Channeled Planar Buried Heterostructure Distributed Feed Back (DC PBH DFB) diode laser emitting at 1.3 μm in butterfly peckage with an internal isolator. The modules provide CW linear output power of 2.5 mW and low distortion.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 5 692 (1996)
Bragg Gratings Photoimprinted in Hydrogen Loaded Optical Fibers
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Bragg grating was photoimprinted on the core of hydrogen loaded commercialized communication fibers using 193 nm ArF excimer laser and silica phase mask. The obtained fiber grating has a reflectivity greater than 90%, and a FWHM bandwidth less than 0.6 nm.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 4 575 (1996)
Franz-Keldysh Shift of the Wavelength of Peak Response of (HgCd)Te Photodetectors
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The Franz-Keldysh shift of the wavelength of peak response of (HgCd) Te detectors has been investigated experimentally. Our experimental measurements show that the Franz-Keldysh effect does have significant strength in (HgCd)Te and may lead to a considerable shift of the optical absorption edge toward the longer wavelength in a strong electric field.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 4 571 (1996)
Radiative Lifetimes of the Highly Rydberg States of Sodium Atom
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

We have obtained the population of the highly excited Rydberg states of sodium atom by two-step excitation using tunable lasers. The field- ionization thresholds for excitation states were measured by using a pulse electric field, which applied to interaction region after the laser excitation. Lifetimes for ns (n=20~24) and nd (n=19~23) states were measured by delaying field-ionization, and compared with the calculation values. The influence of some factors on lifetime is discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 4 567 (1996)
The Limited Maximum Number of Injected Lithium Ions in Electrochromic WO3Film
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The interface potential of WO3 film and lMLiClO4- PC solution and its measurement are discussed. Three kinds of WO3 films with different electrochromism proPerties were made, and their variation of the interface potentials were measured as a function of the number of Li + ions injected into WO3 film. It is found that the limited maximum number of injected Li+ ions is predicable through the variation trendaney of interface potential. The best deposition parameters of thermal evaporation for electrochromic WO3 film are obtained.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 4 563 (1996)
Artificial Colored Reproducing and Processing of Spectrum Images
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Using a code programmed based on the Fortran, spectrum images can be reproduced on the computer screen with artificial colored and multi level grey methods. Processing functions of screen cursor location, instant read out of spectrum data and image rotation were realized. In addition, the contour and 3D graph deduced from the image can also be produced. This code can greatly improve the efficiency and precision in film image data processing.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 3 382 (1996)
Transformation Properties of Gaussion Schell Model Beams
[in Chinese], [in Chinese], and [in Chinese]

In general case a Gaussian Schell model (GSM) beam passing through ABCD optical systems is represented by the superposition of coherent modes.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 3 378 (1996)
Ultralow Speed Measurement by Laser Doppler Velocimetry
[in Chinese], [in Chinese], and [in Chinese]

A ultralow speed measurement system and the experimental results are reported. Its optical system is a four beam two focus differential laser Doppler velocimetry system (LDV) and the signal processing system uses a dynamic phasemeter. The measurement range can be from 1 nm/s to 300 mm/s.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 2 252 (1996)
Luminescence of Porous Silicon/Laser Dye Composite System
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Porous silicon/laser dye composite was obtained by efficiently inserting laser dye into porous silicon. The composite shows luminescent property of both the porous silicon and the laser dye when inserting trace dye. Increasing the insert of dye molecules, luminescence of the composite increases, the rise time becomes faster, the pulse width of the luminescence narrows, and the composite shows mainly the luminescent property of laser dye. The luminescence peak position of the composite shifts clearly to the blue compared to that of the same dye in alcohol solution.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 2 248 (1996)
A Study on PALC Phase Shifting Shearing ESPI
[in Chinese], [in Chinese], and [in Chinese]

Characteristics of phase modulation of a nematic liquid crystal is studied. A new phase shifting shearing ESPI system which uses parallel aligned liquid crystal as a phase modulator is deceloped. This method lincreases the mearsuring accuracy of shearing ESPI by combining phase shifting technology with shearing ESPI. The phase modulation is simple. The correlation fringe method is used for phase calculation. Satisfactory results are acquired in the experiments on deformation measurement.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 2 244 (1996)
RF Excited Packed Waveguide CO2Laser
[in Chinese], [in Chinese], and [in Chinese]

The RF excited packed waveguide CO2 laser have been studied experimentally. When the dimensions of two packed waveguides both are 1×14.5×200 mm3, the maximum output power of 75 W and the maximum efficiency of 10.8% are obtain. This simple structure laser has a single peak beam output at the far field.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 2 240 (1996)
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 12 1836 (1996)
Heat Transfer Coefficient of Architectural Window with Energy Efficient Coating
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The heat transfer coefficient of architectural window with energy efficient coatings is an important parameter which reflects the performance of energy efficient coatings. In this paper, a method is put forword for calculating and measuring the heat transfer coefficient of architectural windows. Some of measured results are presented. it is found that optical coatings can greatly improve the energy efficiency of windows.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 12 1832 (1996)
External Cavity Mode Locked Multiple Quantum Well Diode Laser
[in Chinese], [in Chinese], and [in Chinese]

An external cavity mode locked multiple quantum well diode laser is reported. Its pulsewidth is 2~5 ps, wavelength tuning range is 1.52~1.57 μm, mode locking frequency is 0.5~1.0 GHz, and average output power is 1 mW. This kind of diode lasers can be used as the light source of optical communication.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 12 18291831 (1996)
Plasma Boring of Ultra Intense Laser
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

For studing the plasma boring effect occurring in the ICF fast ignition scheme, a simple pistol model is presented to study the plasma compression and shock generation by ultra intense lasers. Scaling laws are derived for parameters characterizing the process.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 11 1662 (1996)
Optical Limiting in C60/PMMA Composite Based on Singlet Excited State Absorption
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Optical limiting of C60 /PMMA is studied by using 21 ps laser pulse at 532 nm, and the three level model is used for simulation. The results show that the optical limiting is caused by the singlet excited state absorption.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 10 1534 (1996)
Study of Holographic Grating Used for Butterfly Interconnection Network
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Using two equal intensity beams of 0 and 1st diffracted order through a planar slanted fringe volume holographic grating; one can implement the straight forward link line and the other can implement the crossover link line in the butterfly interconnection network. The grating was fabricated on the red sensitive photopolymer plate, and its design principle and fabricating method are given in this paper.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 10 1531 (1996)
Measurement of Spectral Distribution of Hefei Synchotron Radiation in 200~350 nm
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The spectral distribution of the Hefei synchrotron radiation was determined in 200~350 nm, by comparison with the D2-lamp with MgF2 windows, which is a radiometric transfer standard source of NPL. Within experiments error, a good agreement was found between experimental results and value predicted by the theory of synchrotron radiation derived by Schwinger. The difference between experimental and thoretical data is less than 6% at 200 nm and 1.5% and 240 nm.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 1 126 (1996)
Third-Order Nonlinear Optical properties of Poly (2,5-Dialkoxyphenylene)
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The nonlinear optical properties of a soluble and π electron conjugated organic polymer: poly (2,5-dialkoxyphenylene) (abbreviation called PPP) were studied by degenerate four-wave mixing (DFWM) at 532 nm and 1064 nm. The third-order nonlinear optical coefficient and nonlinear refractive were measured, and the figure of merit is discussed to point out the suuitable wavelength for PPP practical application.

Acta Optica Sinica
Jan. 01, 1900, Vol. 16 Issue 1 122 (1996)
Large-Area, Free-Standing X-ray Transmission Gratings
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Large-area, free-standing X-ray diffraction gratings are of great importance in X-ray optics. Experimental tests on the large-area, free-standing transmission gratings made by Hefei National Synchrotron Radiation Laboratory manifest their success in manufacturing. This kind of gratings can be used for X- ray meaurements and applications in various fields from laboratory X-ray sources to astronomy.

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 9 1279 (1995)
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 9 1278 (1995)
Automatic Shadow Moire Topography
[in Chinese], [in Chinese], and [in Chinese]

The phase- shift technique is adopted to the conventional shadow moire topography to improve the measuring sensitivity and compunctional processing. The generation and error of phase-shift and experimental results are presented.

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 9 1275 (1995)
Dynamic Measurement of Slope and Curvature with a Rotating Cone-Glass Shearing Camera
[in Chinese], and [in Chinese]

This paper discusses the rotating cone-glass shearing camera used for dynamic measurement of slope and curvature. The whole process of slope and curvature can be recorded on a single specklegram.

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 9 1271 (1995)
19 fs-Pulse Generation from a Self Mode-Locked Ti:Sapphire Laser
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

As short as 19 fs pulses are generated from a self mode-locked Ti: sapphire laser which consistS of a Ti: sapphire rod of 5 mm long, two quartz prisms and a Xcavity configuration. The intracavity third-order dispersion is compensated properly and the shorter pulses are thus generated favorably.

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 8 1151 (1995)
Fabrication of Soft X-Ray Condenser Zone Plates
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Soft x-ray condenser zone plates with three kinds of parameters are fabricated by holograph-ion beam etching technique. Zone plate condensers are used in our soft xray microscopy experiments which act in combination with a pinhole as a linear monochromator.

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 8 1148 (1995)
The Properties of Faraday Anomalous Dispersion Optical Filter at 422.7 nm
[in Chinese]

In this paper the properties of Faraday anomalousdispersion optical filter at the g Fraunhofer line(422.7 nm) are calculated and discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 8 1145 (1995)
Curve Fitting to Determine IR Optical Constants of Diamond-Like Films
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A transmittance curve fitting method was used to determine the IR refractive index, absorption coeffecient, thickness and surface roughness of diamond-like films. A mathematical model to calculate the transmittance function of diamond-like films on silicon substrate is introduced. The experimental measurement and curve fitting results are given.

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 8 1140 (1995)
Double Phase Conjugation in Ce:KNSBN Crystal
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

In this paper we for the first time report the double phase conjugation in Ce:KNSBN crystal. It was also observed that the self-pumped phase conjugation and fourwave mixing have been produced with the same double phase conjugate configuration.

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 8 1136 (1995)
Electric Field Distribution in Active LayerOf GaAs/GaAlAs LD Array
[in Chinese], [in Chinese], and [in Chinese]

A new model of the injected current spreading in the active layer for LD arrayis presented in this paper. Regarding the electric field distribution in the lating region as asynthetical result of each unit, we also showed and explained the experimental result byusing Continuous Wave Electro-optic Probing (CWEOP) method to detect the electricfield distribution in the active layer of LD array.

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 7 958 (1995)
Automated Profilometry of 3-D Diffuse Objects byUsing Cosine Transformation
[in Chinese], [in Chinese], and [in Chinese]

A new method of automatitally reconstructing the 3-D surface of an objectfrom the deformed grating pettern is proposed. The method can automatically andaccurately obtain phase value at every pixel point without assigning fringe orders by usinga discrete cosine transform algorithm. It is flee from the errors caused by the higherharmonic components and the variation of light level. Theoretical analysis andexperimental verification are presented.

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 7 953 (1995)
Up-Conversion Effect of Erbium Doped LiNbO3Crystal
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The frequence up-conversion effect, the absorption spectra of Er:LiNbO3 crystal and the lifetime of the 4S state as well as its temperature dependence arereported for the first time in this paper. The up-conversion mechanism and the possibilityof laser action of the crystal are discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 7 948 (1995)
A Novel Optical Fiber Non-Contact Accelerometer
[in Chinese], [in Chinese], and [in Chinese]

A novel non-contact fiber optic accelerometer is presented. The velocity of a moving target is sampled at different times by two beams originating from the same laser but with different feed path lengths. The acceleration of the target is measured by heterodyning the two Doppler shifted return beams. By directing each return beam to the detector via the feed path taken by the other beam, equal path lengths are ensured relaxing the coherency requirements of the light source.

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 6 829 (1995)
Experimental Study on Pulse Amplitude Stablization in a Q-Switched Single Longitudinal Mode Nd:YLF Laser
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

An optical-electron feedback circuit based on ultra fast response GaAs photoconductive switch was applied to control a Q-switched single longitudinal mode Nd:YLF laser with negative feedback. The output pulse amplitude stability of the laser was enhanced and the perturbation less than ±3%.

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 6 826 (1995)
Float Polishing Subnanometer-Smooth Surface
[in Chinese], [in Chinese], and [in Chinese]

This paper is a summary about our current work on supersmooth surface by float polishing. The basic configuration of a prototype machine is described, and some parameters for polishing subnanometer-smooth surface are presented with the recent measurement results of surface roughness.

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 6 824 (1995)
Studies of (Nd,Ce): YAG Raman Shifting Laser with Compound Output Mirror
[in Chinese], [in Chinese], and [in Chinese]

The theoretical and experomental studies of (Nd,Ce):YAG Raman shifting laser in high pressure CH4 gas with compound output mirror composed of a partial reflective concave and a auxiliary plane mirror are reported in this paper.We have got 12 mJ pulse Raman laaser in 10 J input,and calculated the fundamental mode beam parameters of the fundemental freqiency field.

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 4 509 (1995)
Laser Diode Pumped Nd:FAP Laser Oscillator
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A laser-diode-pumped Nd:FAP laser oscillator is reported in this paper. A slope efficiency of 31% has been obtained with the transmission of output coupler of 8%,while the repetition rate is 100 Hz.The performance of LD pumped FAP and YAG lasers is compared, Nd:FAP is demonstrated to be a promising laser medium fitting for LD pumping.

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 4 504 (1995)
Space Intergrating Acousto-optic Correlator Using an Extraodinary AO Device
[in Chinese], and [in Chinese]

A space intergrating acousto-optic correlator (SIAOC) using one extraodinary acousto-optic device with two oppositely directed channels is proposed. Some interferencefree experimental results for analog radar signal (high- frequency signal modulated by rectangular pulses) through directed detection are given. When the width of the rectangular pulses is 10 μs, the correlative gain is 16 dB.

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 3 381 (1995)
Studies on H-Terminated Si(100)Surfaces by Second Harmonic Generation
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

In this paper, we report out experimental results of optical second harmonic generation from clean Si(100)2×1),Si(100)(2×1)-H and Si(100)(3×1)-H surfaces.For the clean Si(100)-(2×1)surface and the Si( 100)(3×1)-H surface,the second harmonic Intensity decreased monotonlcall with increasing temperature.For the(2 ×1) monohydride Si(100)surface,the second harmonic intensity varied on the temperature not monotonkically,but has the maximum at about 470 K.Structure and sample temperature could be monitored by the second harmonic intensity and the tempeerature dependence of second harmonic intensity.

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 3 377 (1995)
Second Harmonic Generation of TEA CO2Laser in the AgGaSe2Crystal
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

AgGaSe2 crystal of φ20×60 mm has been grown by the method of oven temperature drop. The frequency-doubled (5.3 μm) output and the power conversion efficiency of 1.12% have been obtained for second harmonic generation of TEA CO2 laser (10.6 μm). The pumped and the damaged threshold are about 3 MW/cm2 and 11 MW/cm2, respectively. We have also discussed the effect of the beam divergence on the second harmonic conversion efficiency.

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 3 374 (1995)
Single-Frequency Operation of Nd:YVO4Laser
[in Chinese], and [in Chinese]

Single-frequency output power of 155 mW has been obtained in 2% doped Nd :YVO4 crystal pumped with a 1 W laser diode. Continuous wave thresholds of 226 mW have been observed with slope efficiencies of 33%. The linewidth is less than 10 MHz.

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 3 371 (1995)
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 2 256 (1995)
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 2 255 (1995)
Fabrication of SiGe Rib Waveguides X Branches
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Based on the realization of low loss Si1-xGex/Si single-mode rib waveguides,we developed the Si1-xGex/Si "X" branches with the cross waveguides. These structures were fabricated from SiGe grown by molecular beam epitaxy (MBE). The branchesdemensions are determined by Si1-xGex/Si large single-mode conditions and propagationfeatures of the "X" cross waveguides using the beam propagstion and effective indexmethod.

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 2 252 (1995)
A New Structure of 1×4 Single-Mode Optical Fiber Splitters
[in Chinese], and [in Chinese]

Based on the linearly coupled mode equations, we have analyzed couPledpoWer characteristics of the coupling system consisting of five optical fibers. A mothed tofabri ̄ new Structure of 1×4 splitters is proPOsed and experimentally demonstrated.The characteristics and dimentions of the obtained 1×4 splitter are almost the same ascommon 2×2 coupler.

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 2 248 (1995)
Application of the X-Ray Picosecond Framing Camera in Intense X-Ray Pulse
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Image distortion of the electro-optical tube X-ray framing camera becomes serious for intense X-ray pulse operation because of the space charge effect. This paper describes the characteristic of MgF2 photocathode and its first application in the framing camara. The space charge effect has been reduced and the clear pictures have been obtained for the intense X-rays.

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 12 1738 (1995)
Chaos Behaviours in Dual Coupled Class-B Laser
[in Chinese], and [in Chinese]

The dynamical behaviours in dual coupled class-B laser were studied. This system can give CW, self-pulsing and chaos outputs. Period-doubling apptoach to chaos was found in the system.

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 12 1735 (1995)
Fabrication of SOI Wavelength Demultiplexer
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Silicon-on-Insulator (SOI) wavelength demultiplexers are studies by using thelarge cross-section single-mode rib waveguides conditions and the two-mode interferenceprinciple in silicon direct bonding SOI with bsck-polishing.They are fabricated by usingKOH anistropic etching. Their insertion loss are measured to be down to 4. 81 dB at thewavelength of 1.3 μm, and crosstalk is less than -18.6 dB at 1.3 μm.

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 11 1598 (1995)
Stimulated Raman Scattering in Oxygen or Oxygen-Helium Mixing Gas Pumped by a Q-Switch Frequency Doubled Nd:YAG Laser
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

This paper presents the stimulated Raman scattering in high pressure industraloxygen or oxygen-helium mixing gas pumped by a Q-switch freqency doubled Nd:YAGlaser. The relationship between Stokes energy converting efficiency and the pumpenergy, and gas pressure has been investigated. It is also discussed how to restrainsecond-order Stokes, et al.

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 11 1594 (1995)
[in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 10 1471 (1995)
Study on OPtical Propertics of (Ti, Al)N Films
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The optical properties of (Ti, Al)N thin film have been studied and the transmission and reflection spectra have been analysed carefully. Using Hadley equations, the optical constants, n-refractive index, k-extinction coefficient of (Ti, Al)N films were determined. According to the transmission spectrum of (Ti, Al)N film, the optical gap energy of (Ti, Al)N film was calculated.

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 10 1467 (1995)
Electron-Trapping Mechanism of Sm:Cas
[in Chinese]

After exposed to ultraviolet light, the strong infrared optically stimulated luminescence was obsered in CaS singly doped with Sm. It is result from the electron transfer between Sm ions at different sites. The optical spectral properties and electrontrapping mechanism of Sm: Cas are reported in this paper.

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 10 1463 (1995)
Bi-Cell Detector Algorithm for Calculating Misalignment
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A unique alignment algorithm-hi-cell algorithm is presented. With the alignment scan curve generated from the dark field alignment system, a bi-cell detector implemented in software is used for calculating the misalignment. In the bi-cell detector algorithm the symmetry point over the alignment scan curve is calculated as the ideal alignment point instead of the peak value point or other characteristic value point. Results show that the alignment accuracy better than 0.11 μm (3σ) can be obtained. The princi

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 10 1458 (1995)
The Green Function Solution of Van Der Pci Equation
[in Chinese], and [in Chinese]

The Fokker-Planck equation is solved by using the propagstor method. TheGreen function is calculated by using the local harmonic approximation method. Thepaper also discusses the applications in the quantum optics.

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 1 126 (1995)
The Transmisson of Electromagnetic Waves in Multilayer Media
[in Chinese]

In this paper the relations between the amplitudes of electromagnetic waves propagating in multilayer media and those of incident waves on surface are deduced. And a generating function by which the transmitted waves in every layer can be generated isintroduced.

Acta Optica Sinica
Jan. 01, 1900, Vol. 15 Issue 1 122 (1995)
Computer Moire Technique Used for 360° Measurement of Surface Topography of 3D Objects
[in Chinese], and [in Chinese]

In this paper, the principle of computer moire used in 3D 360° object surface measurement is discussed. The experiment verifies that the computer moire method is a very sucessful method and the result can be got automatically with high speed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 9 998 (1994)
Reverse Saturable Absorption and Optical Limiting of the C60/PSt Composite
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The preparation method of C60 in PSt (Polystyrene) composite is reported. The linear absorption spectrum of C60 in PSt have been measured. The reverse saturable absorption and optical limiting of C60 in PSt have been studied.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 9 995 (1994)
Reflection of Electromagnetic Pulse from an Oncoming Ionization Front
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Freuency up- conversion, pulse compression, and energy amplification of electromagnetic pulse upon the reflection from an oncoming ionization front is studied, the conditions favorable for these purposes are discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 9 992 (1994)
Binary Optical Element for Laser Beam Shaping
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A binary optical element is designed based on computer generated hologram for shaping the profile of laser beam from Gaussian to top-hat. As it is a binary optics, so the diffraction efficiency is four times than the holographic one's. The approach is easy in fabrication. The design and experimental results are presented.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 9 988 (1994)
Axis-Asymmetric Resonator Analysis Using an Iterative Computing Method of Complex Rays
[in Chinese], [in Chinese], and [in Chinese]

A method of representing astigmatic beams by complex rays is used for analyzing axis-asymmetric resonators. Numerical iterative calcalations were Performed for a folded resonator with general astigmatism to show the application of the method.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 9 984 (1994)
Optical Phase Conjugate in Azo-Dye-Doped Liquid Crystals Cell
[in Chinese], and [in Chinese]

An observation of optical conjugation in azo-dye-doped liquid crystals cell is reported for the first time. Its response time, diffraction efficienty and threshold intensity were measured, and the resolution was analysed. It is shown that it's a novel promising phase connjugate device.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 9 1005 (1994)
Transient Photoluminescence in Amorphous CdSe
[in Chinese], and [in Chinese]

Time-resolved photoluminescence (PL) deary and peak energy shift with time of PL emission spectrum in amorphous CdSe. are Studied. The initial dynamics of the thermalization and radiative recombination of photogenerated carriers are analysed with the geminate-pair model.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 9 1001 (1994)
Fine Hole Drilling Using the Phase Conjugate Laser
[in Chinese], and [in Chinese]

Using the Nd:YAG laser with the SBS-phase conjugate mirrow based on SF6 gas, the laser drilled hole on a 0.1 mm thik blade has been reported in this lecture.The primary experimental results show, that the fine hole with the exit diameter of 20 μm and the entrance diameter of 30 μm has been obtained due to the small laser beam divergence of this SBS-phase conjugate laser.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 8 894 (1994)
CW Single-Frequency Operation of a Diode Laser-Pumped Nd:YAG Laser
[in Chinese], [in Chinese], and [in Chinese]

Single-longitudinal-mode, TEM00 output of 55 mW has been obtainded from a end-pumped twisted-mode cavity Nd:YAG laser. Continuous wave thresholds of ~300 mW have been observed with slope efficiencies of 23%. The linewidth is less than 25 MHz.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 8 891 (1994)
Extension of the Bandwidth for a Far-Infrared Free-Electron Laser
[in Chinese], [in Chinese], and [in Chinese]

Extension of the bandwidth is investigated for a waveguide free-electron laser (FEL) by adjusting the waveguide dimensions, or the electron beam energy, or the period and strength of the wiggler. A far-infrared FEL oscillator with the bandwidth of 400 μm is designed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 8 886 (1994)
Measurement of the Faraday Effect of Magneto-Optical Film in Alternating Magnetic Fields
[in Chinese], [in Chinese], and [in Chinese]

The experimental apparatus for measuring the peak value of the Faraday rotation F induced by alternating magnetic field is set up. The sample used here is a magneto-optical film Prefared by liquid Phase epitaxy. By measuring the fundamental and the second harmonic of the photodetector current at a angle away from cross setting of P, A, the F can be calculated. The method is simple and accurate and can be used at any frequency.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 8 882 (1994)
Fabrication of SOI Single-Mode Rib Wavegulde with Large Trapezoidal Cross-Section
[in Chinese], [in Chinese], and [in Chinese]

A SOI (silicon-on- insulator ) single- mode rib waveguide with large trapezoidal cross-section formed by SDB (silicon wafers direct bonding) process has been fabricated. And the SDB SOI rib waveguide losses are below 0.85 dB/cm by measurements at a wavelength of 1.3 μm.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 7 783 (1994)
Study on the Refractive indices of PbBr2Crystal
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The orientation of the principal refractive aams Of PbBrZ crystal has beendetermined and itS principal refractive indices have been measured.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 7 781 (1994)
Equivalent Reflectance Of Baffle with Vanes
[in Chinese], and [in Chinese]

In this paper, the equivalent reflectance of diffusive baffles with vanes is discussed. After comparing several equivalent reflecamces introduced in literatures, a more appropriate model is proPOSed, in which not only the scattering and diffraction from vanes edge but also the influences of the segmentation of baffle are considered.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 7 777 (1994)
A Novel Method for Refractive indices Measurement of Optical Waveguides
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

In prism-waveguide coupling experiment we found that the reflected light through the prism carried all information of waveguide refractive indices. According to the intensity variation of the reflected light, the refractive indices of optical waveguide,including effective indices of waveguide modes and substrate index, can be measured precisely. Then the refractive indices at different depths can be determined by curve fitting.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 7 773 (1994)
Three-Dimensional Laser Doppler Velocimeter Using Frequency Shift Separation
[in Chinese]

A new three-dimensional laser Doppler velocimeter (3D LDV) by only using frequency shift separation method has been developed. Simultaneous measurementS of three velocity components are realized by a single color He-Ne laser and one photodetector with simple transmitting and receiving optics. The signals corresPOnding to different velocity components are distinguished by three different optical frequency shifts introduced by three Bragg cells, and separated by band-pass filters. A novel and simple four-beam transmitting optics which contains three sets of dual-beam LDV systems is proposed, and the design specification of the 3D LDV system is presetned. The measuring accuracy of the on-axis component is also discussed in this paper.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 7 768 (1994)
Lens Design of the Flat Field, Apochromatic CF Microscopic Objective
[in Chinese]

This paper discussed the scientific meanning and the main design idea of the flat field, apochromatic CF microscopic objective which is a new model of microscopic objective since 1980' s. The paper discussed the main idea, correction of the secondary spectrum and the petzval sum, and the evaluation of image quality. Finally the author evaluated the design example in terms of the Strehl ratio S. D.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 5 558 (1994)
Analytic Method for Calculating Propagation Comstant of TM Waves at a Nonlinear Interface
[in Chinese], and [in Chinese]

Exact dispersion relations and an analytic formula for calculating propagation constant and the power flux for TM guided waves at a nonlinear interface have been obtained. The advantage of this method is that the detailed field distrubutions are not necessarily known for solving the dispersion relations and also for calculating the power flux.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 5 554 (1994)
Sensitivity Analyses of Light Scattering and Extinction Parameters to the Aerosol Refractive Index
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

By using Mie theory of light scattering, under different type of the Junge size distribution, the numberical calculations were carried out about the sensitivity of the ratio of aerosol extinction to backscatter, extinction and backscatter to real and imaginary parts of aerosol refractive index. Some useful conclusions were obtained.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 5 551 (1994)
Hyperfine Structure Measurements on High-Lying Levels of Lanthanum by Laser Fluorescence Spectroscopy
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

By using laser fluorescence spectroscopy we measured the hyperfine structures of three second-step transitions(0 cm -1→1 6856 cm-1→34272 cm-1),(3010 cm-1→20082 cm-1→36853 cm-1),(3010 cm-1→20082 cm-1→37544 cm-1) in a La hollow cathode discharge lamp. The a coefficients of 34272 cm -1,36853 cm-1,and 37544 cm-1 levels have been calculated. The results given in this paper are first reported.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 5 548 (1994)
Primary Study of Deep-Etch Synchrotron Radiation Lithography
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 4 447 (1994)
Absorption Spectrum of Optical Glasses Doped with Fullerenes
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

C60/C70; optical glasses; absorption spectrum

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 4 445 (1994)
Observation of Mode Shift of Nd-Glass Mirospherical Cavity
[in Chinese], [in Chinese], and [in Chinese]

In this paper, we report the mode shift of Nd-glass microspherical cavity caused by small variations of cavity size. The influence of mode shift on pump coupling is analysed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 4 442 (1994)
Study on High Energy Long Mode-Locked Pulse Train Nd:YLF Laser
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

High energy long mode-locked pulse train in Nd: YLF laser was studied by dyamically control the cavity Q-factor. The total length of the mode-locked pulse train was about 16 μs, energy was 2.5 mJ, single stable pulse duration was 4 ps.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 4 439 (1994)
Initial Experiments of An Inside-Pumped Miniature Nd:YAG Tube Laser
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The design and experimental results of an inside-pumped miniature Nd:YAG tube laser are presented in this paper. The slope efficiency reachs 2.73%. The pulsed laser energy of 3 J has been obtained.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 4 436 (1994)
Temperature Dependence of Photorefractive Effects in Fe:KNbO3
[in Chinese], [in Chinese], and [in Chinese]

This paper presents the experimental investigation of temperature dependences (290~380 K) of photorefractive effects in Fe:KNbO3. Results of two-wave coupling under different experimental configuration and self-pumped phase conjugstion in special Cut crystal are demonstrated.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 3 334 (1994)
Plasma Ablative Shock Wave and Its Time Evolution
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The shock wave generation by plasma ablation is studied in this paper. The interdependent relations between various hydrodynamic parameters at the shock front and ablative flout are determined, the generation and temporal evolution of ablative shock are discussed in details.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 3 331 (1994)
Kerr Effect in Birefringence and Optic Logic Gate
[in Chinese], [in Chinese], and [in Chinese]

In the paper,The Kerr effect in single mode birefringence fiber is studied in detail. The related advantsge is discussed when it is used as fiber optic logic gate. In addition, itS theoretical analysis and calculated data as well as experimantul setup are given The " 1/0" state of intensity model fiber logic gate is defined and the pulse width of output light is measured. The experimantal resultS coincide well with theoretically calculated data.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 2 222 (1994)
GaAs/GaAlAs Heterostructure Rib Waveguide Stepped Δβ Coupler
[in Chinese], [in Chinese], and [in Chinese]

GaAs/GaAlAs heterostruture rib waveguide coupler with "stepped Δβ" Schottky electrodes has been investigated by using ion-etching and liftoff mask techniques, and optimization design of device structure and lowering epitaxy layer carrier concentration. Total losses of 10 dB and extinction ratio of 26.8 dB are obtained for single-mode operation at 1.3 μm.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 2 217 (1994)
Programmable Optical Parallel Fuzzy Logic Gated
[in Chinese], and [in Chinese]

A cascadable optical system for parallel fuzzy logic gates is proposed. Sixteen fuzzy logic operations can be realized by programming the polarization states of halfwave plates. The experimental results are given.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 12 1341 (1994)
Temperature Effect of Phase Conjugation Wave in Doped Lithium Niobate
[in Chinese], and [in Chinese]

The temperature effect of phase conjugation wave was investigated experimentally in doped lithium niobate. It is found that the conjugation wave has significant temperature enhancing phenomenon and which is explained by using the mechanism of Amodei' s electron diffusion.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 12 1337 (1994)
SHG Cherenkov Radiation in LiNbO3Waveguide
[in Chinese], and [in Chinese]

In this paper, the optical second harmonic generation (SHG) of cherenkov scheme in channel waveguide was analized and the condition of waveguide for Cherenkov type SHG was discussed in detail. We obtained the SHG power at wavelength of 0.53 μm by coupling 1. 06 μm fundamental power into the guide. The conversion efficiency is about 0.9% corresponding to the 10 mW input power.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 12 1333 (1994)
Performance of Optical Limiting in PDATS with ps Pulse
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Optieal limiting in 5-(2-methylthio-4-methyl-5-pyrimidinyl)-2,4-pentadiyne-1-ol tosylate (PDATS) in solution was performed using 21 ps laser pulses at 532 nm wavelength. By employing this material with high linear transmittance, low threshold and low clamped output of Eth=150 mJ/cm2 and Ec=180 mJ/cm2,respectively were ablained.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 12 1329 (1994)
Fabrication of X Type Crossing Waveguide Structure Constructed by Large Single-Mode Rib SOI Waveguide
[in Chinese], [in Chinese], and [in Chinese]

X type crossing waveguide structures constructed by large single-mode rib SOI (Silicon-on-insulator) waveguide have been fabricated. The SOI structure is formed by SDB (silicon wafer direct bonding) process. When crossing angle of the crossing waveguides is equal to 2°, their crosstakles is below to -20 dB, their radiation losses is below to 0.3 dB, and their propegstion losses of the direct channels are measured to beapptoximately 0.85 dB/cm at a wavelength of 1.3 μm.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 11 1230 (1994)
Reduction of Thermal Background of RENFWM Spectrum by Time-Delayed Method
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

We demonstrate that with the time-delayed mathod the Raman-resonance hidden in the thermal background can be revealed and the Raman-enhanced nonlegenerat6 four-wave mixing spectrum converts to a normal asymmetric lineshape with foe nonresonant background originating from the molecular-reortenactional grating. The experimental results are in good agreement with the theoretical predictions.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 11 1227 (1994)
Dispersion Equations of Inhomogeneous Planar Optical Waveguides
[in Chinese]

A new method for obtaining the analytical dispersion characteristics of planar waveguides with arbitrary refractive index profile is presented. The method is based on the transfer matrix theory and a new interpretation of the WKB approximation is proposed. A comparison with other methods and the exact numerical results shows that our method is much more accurate than the ordinary WKB method and other existing approximate methods.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 11 1223 (1994)
Influence of High-lStstes on the Autoionization Spectra
[in Chinese]

A combination of multichannel quantum-defect theory with the K reaction matrix has been used to imvestigate the influence of high-l 3pnl, (l=4) configuurations on the Mg 3pnd (j=3) autoionization spectra. The introduction of the 3Pug (J=3) configurations allows us to construct a complete model of the 3pug (J=3) autoionization process. Physical mechanism of some experimental phenomena have been related to the derailed structures of the autoionization spectra. Our theoretical results agree well with the published experimental spectra.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 11 1219 (1994)
Determination of Angular Distributions of Excimer Laser Induced Plasma Near YBa2Cu3O7-xTarget Surface
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Axial and radial distributions of emission spectral intensities from XeCl excimer laser induced plasma near YBa2Cu3O7-xsuperconducting forget surface were measured by using an Optical Spectroscopy Analyzer (OSA). The ansular distributions of excited species in the plasma plume were obtained with curve sitting method on the assumption that each kind of excited species had corresponding uniform radiation probability over the plasma region respectively. The plasma plume exhibited a cos n θ spread and the value of n is between 2.78 and 7.63. The results were investigated as the functions of laser spot energy density and background oxygen pressure respectively.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 11 1215 (1994)
Effect of Beam Size on Spatial Resolution of the PTR Systems
[in Chinese], and [in Chinese]

The definition of spatial resolution in the PTR (photothermal radiometry)system is given. The influence of incident beam size on spatial resolution is investigated.The theoretical anlysis and practical measurements show that focused incident beam improves the spatial resolution of the system greatly.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 10 1117 (1994)
Observation of Hyperfine Coherence Resonances in 87Rb with Microwave Modulated Semiconductor Laser
[in Chinese]

Hyperfine coherence resonances with ΔmF=0,±1,±2 are observed in 87Rb vapor optically pumped with a microwave modulated semiconductor laser. The O-O(F=2,mF=0) hyperfine coherence resonance may be used as a reference of the atomic clock.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 10 1114 (1994)
Stability of Backward Raman Compressor
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Stability of pulsewidth of backward stokes output is dominated by the stability of pump light. The theoretical prediction is verified by experimental results.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 10 1110 (1994)
[in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 1 112 (1994)
The output property of a nonlinear Fabry-Perot Interfreometer
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

This paper discusses the output property of a Fabry-Perot interferometer filled with a nonlinear medium. Because of the optical field induced refractive index, the transmissivity across the monochromatic beam through the interferometer depends on distribution of the beam intensity. The output beam is different from the input. As the reflectvity of two planes increases, the distinction changes clear, and there is a change close to discontinue.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 1 107 (1994)
Experimental study of superbroadening continuous spectrum generation
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

This paper reports for the first time the experiment of superbroadening continuous spectrum (100 nm) generated by pumping two kinds of fibers successively with intensive laser. The experimental phenomena are explained in details.

Acta Optica Sinica
Jan. 01, 1900, Vol. 14 Issue 1 102 (1994)
Transient all-optical switching in C60molecules
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

We have firstly demonstrated the transient all-optical switching for C60 in toluene pumped by a control light and probed by a signal light. The lifetime of C60 (3T1) can be deduced from the switching time.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 9 862 (1993)
Effect of polarization spectroscopy in multitep excitation and ionization of atoms on ionization efficiency
[in Chinese], and [in Chinese]

In this peper, the seventeen real motion equation of atoms were shown for the first time inconsiderlng the polarization choices of laser lights. The importance of polarization spectrcoscopy in thedetermination of ionization yields of multi-step excitation and ionization of atoms (MSEIA) wasshown.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 9 859 (1993)
Prism coupling method for refractive index measurement of optical wave guide substrates
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Careful study in the prism coupling method on refractive index measurement of optical waveguide substrates is given. The refractive indices of quartz, CaF2, LiF substrates and "C-813-8" gum plate were measured in two kinds of incident conditions and valuable measurement results are got.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 9 855 (1993)
Large scene depth rainbow hologram and its viewing conditions
[in Chinese]

The Scene depth of rainbow hologarm is analysed and discussed in detail based on the line-element hologram theory. It is theoretically demonstrated that the rainbow hologram can be used for displaying objects with large scene depth under certain viewing conditions. The rainbow holograms with scene depth of 450 mm are obtained in experiment.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 9 850 (1993)
Investigation on the reverse saturable absorption of C60α-methylstyrene/styrene copolymer
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Solid plates of C60 α-methylstyrene/styrene copolymer have been obtained. The light transmissive properties of the plates were studied with a 10 ns, 530 nm laser beam. The reverse saturable absorption process, corresponding to optical limiting performance was observed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 8 766 (1993)
The optical bistability in fullerenes
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

We have observed for the first time the phenomena of optical bistability-switching for the film of C60/C70 with all-optical method of the nonlinear F-P cavity. The on-off time of optical switching is about 10 ns.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 8 763 (1993)
Study of the overlapping ratr of selfoc lens arrays
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The overlapping rate of selfoc lens arrays is discussed and its influence on resolution and illuminance distrbution is analyzed in this paper. An important criterion is obtained for the manufacture of selfoc lens arrays after a series of measurement of single selfoc lens and lens arrays. The empirical formula concerning the unevenness of illuminance is derived from experimental data.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 8 759 (1993)
Influence of the adiabatic-magnetic-field distribution at the entrance of wiggler on the output power and efficiency in a free-electron laser
[in Chinese], [in Chinese], and [in Chinese]

The influence of the adiabatic-magnetic-field distribution at the entrance of wiggler on the output power, gain, and efficiency in a free-electron laser is investigated in terms of nonlinear simulation. Results show that the distribution f(kwz) = (kwz/2πNw)3 is better and closer to the measured data than both f=sin2(kwz/4Nw) and f=(kwz/2πNw)2.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 8 756 (1993)
Heterodyne common path surface profilometer
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

As a modified heterodyne profilometer the heterodyne common path surface profilometer for measuring surface roughness is described. The profilometer is not sensitive to mechanical instability and temperature variations. The actual height resolution is 0. 1 nm and this system could be developed into a standard instrument for surface roughness measurement.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 7 670 (1993)
Study of laser phase imaging radar
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

By using the principles of diffuse reflection laser phase ranging with non-cooperation turget to analyze and to design the key unit techniques, a prototype of laser phase imaging radar is developed which is suilable for the visual guiding system of autonomous carriage.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 7 667 (1993)
Angle-sensitive characteristics of volume holographic reflection element with two groups of peak planes
[in Chinese], and [in Chinese]

The characteristics of wavelength of dark-band valley in the transmitted spectrum of dichromated gelatin (DCG) holographic reflection element against the angles of incident beam are investigated experimentally. The use of holographic reflection element with two groups of peak-intensity planes as the holographic angle-sensitive element (HASE) is presented. The HASE has high angular sensitivity and the property of sensitizing to incident beam within very wide angles. The influences of experimental parmeters including the processing conditions and the ratios of reference to object on the minima and bandwidths of dark-band of transmitted spectrum are also analysed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 6 572 (1993)
Accurate analysis of non-collinear acoustooptic interaction in TeO2crystal
[in Chinese], [in Chinese], and [in Chinese]

Based on the analysis of the design theories[1,2] for non-collinear acoustooptic tunable filter (AOTF), this paper analysed and accurately calculated the angular dependence between the acoustic polar angle θa and incident light polar angle θi for TeO2. θa-θi curve satisfied the parallel- tangents momentum- matching condition for non- collinear AOTF with a maximum angular aperture is obtained. The resulted curve obviously improved the θa-θi curve of Chang[2], and it provides a solid theoretical basis for the design of TeO2 AOTF.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 6 568 (1993)
The implementation of FPS interconnection network using 2-D grating
[in Chinese], [in Chinese], and [in Chinese]

In this paper, a new method using 2-D diffraction grating to implement the folded perfect shuffle interconnection network is proposed. This method is simple and feasible, the experimental results prove its effectiveness.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 6 564 (1993)
Theoretical analysis of photoacoustic Raman spectroscopy in condensed matter
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The theoretical analysis of photoacoustic Raman spectroscopy(PARS) in condensed matter is presented. The general expressions of PARS signal are derived for the cases when two modulated continuous laser beams or two pulsed laser beams are used as the activation source. The theoretical value is estimated.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 6 557 (1993)
A new method for improving the environmental stability of dichromated gelatin holograms
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Polyvinyl alcohol and some additives were introduced into the gelatin ammonium dichromate system for making Lippmann holograms. Experimental results have shown that these holograms possess better environmental stability than conventional dichromated gelatin holograms. Tentative analysis is also presented about the functions of the polyvinyl alcohol and the additives added. Mechanism of the improved environmental stability is discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 6 552 (1993)
Propagation and compression of high intensity pulse in GVP optical fibers
[in Chinese], and [in Chinese]

Taking into account of the fourth- order nonlinear refractive index, we have obtained the soliton solution of the nonlinear equation which governs the propagation of optical pulse in group velocity dispersion (GVP) single-mode fibers. And we point out that there is a intensity threshold for the sech-type pulse compression.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 5 478 (1993)
Measurements of weak absorption of optical coatings for multi- wavelength by photothermal deflection technique
[in Chinese], [in Chinese], and [in Chinese]

The basic principle of weak absorption measurements performed with photothermal deflection technique is discribed. An experimental setup with multiple pumping lasers has been constructed, the testing procedure and the results of a simple measurement example are presented.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 5 475 (1993)
Optical properties of the diluted magnetic semiconductors Zn1-xFexSe thin films
[in Chinese], and [in Chinese]

The polycrystal thin films of the diluted magnetic semiconductors Zn1-xFexSe were prepared by vacuum evaporation. The structure and composition of the films were examined by X-ray diffraction and scanning electron microscopy. Optical absorption data showed that the energy gap E 8 decreases linearly with the composition x of Fe2+ ions. The best fitted relation is Eg=2.722-2.224x.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 5 470 (1993)
Noise of semiconductor laser arrays
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

We report in this paper the measurement results of the relative intensity noise (RIN) in GaAs-AlGaAs laser arrays and the comparison with that of single stripe lasers. The results are in agreement with the noise theory based on the rate equation. The experimental measurements include relative intensity noise versus drive current, modulation frequency and temperature. And in these circumstances the theoretical prediction that the maximum of the relative intensity noise occurs when the lasers run exactly at their threshold current level is examined.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 5 466 (1993)
[in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 4 384 (1993)
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 4 383 (1993)
Pulsed differential PARS of liquid
[in Chinese], [in Chinese], and [in Chinese]

Nonlinear Raman spectrum of various of liquids is detected by using pulsed photoacoustic method. The cause of limiting the detect sensitivity of PARS techenique, mainly due to linear absorption, is discussed. Furthermore, an improvement method, differential method, is used to elimnate the disturbance from linear absorption. The detect sensitivity of PARS techenique is increased, so that the Raman spectrum of low concentration matter and the weakline of Raman spectrum can be detected. The probability of using differential PARS techenique to detect contaminant is discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 4 379 (1993)
Optical properties of transparent and conductive Cd2SnO4films
[in Chinese], and [in Chinese]

The transmission and reflection spectra at wavelength between 0.2 and 6.0 μm, and photoluminescence spectra of Cd2SnO4 films deposited by RF reactive sputtering from a Cd-Sn alloy target have been measured. The optical properties of Cd2SnO4 films are analyzed and calculated theoretically in detail.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 4 375 (1993)
Technolohy of measuring high resolution spectra with an OMA system
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The optical multichannel analyzer (OMA) is a modern instrument for mesuring spectra. But there is a contradiction between the spectral resolution and the mesurable width of simultaneous spectra. In this paper, a method has been given out which can enhance the resolution ten times or even one hundred times without reducing the width of simultaneous spectra. The high resolving spectra of an OMA system can be easily obtained with this method.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 4 371 (1993)
Rotating aperture cone glass shearing speckle photography
[in Chinese], and [in Chinese]

In this paper, rotating aperture cone glass shearing speckle photography used for dynamic problems is proposed. The whole dynamic process can be recorded on a single specklegram, and the derivatives of displacements of every moment can be obtained by whole-field filtering.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 3 287 (1993)
Study of the frequency off set-locking technique of CO2laser
[in Chinese], [in Chinese], and [in Chinese]

In this paper the frequency offset-locking techniqe of CO2 laser, one of the element techniques in CO2 laser heterodyne is studied. Beat frequency locking between two CO2 lasers with free oscillation has been realized. Having taken some measurement to reduce the affection of circumstance, the frequency traceability of 0.5 kHz (τ=10 s) has been obtained. Its central frequency can tuned continuously in the range of 2~20 MHz.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 3 284 (1993)
Optical absorption of ZnSe-ZnTe strained-layer superlattices
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Absorption spectra of ZnSe-ZnTe strained-layer superlattices were measured at room temperature. Two step-like absorption edges corresponding to the transitions from the first heavy- and light-hole to the first electron level were observed. The valance band offset of ZnSe-ZnTe superlattices were determined from the band gap of the superlattice to be 1.10 eV.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 3 281 (1993)
Nonlinear optical property of cresyl violet
[in Chinese], [in Chinese], and [in Chinese]

This paper studies the nonlinear property of cresyl violet. By using degenerate four-wave mixing, the 3rd nonlinear electric susceptibility X3=2.0×1010 esu have been obtained. Afterwards,its relaxation time was measured as τ21=163 ps, by using pulse correlation technique.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 2 189 (1993)
Interferometric approach method for measuring refractive index of liquid samples
[in Chinese], and [in Chinese]

A new interferometric technique for measuring liquid refractive index (RI) with high accuracy has been developed, which is directly traceable to the wavelength of He-Ne laser. The accuracy of this method is improved by increasing the optical path of step. The experiment revealed that the temperature distribution nonuniformity in the liquid limits the practical uncertainty of liquid RI measurement from 1×10-6 to 4×10-5 (2σ) depending on its temperature coefficient although much finer resolution can be easily achieved with this method.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 2 185 (1993)
Nonapproximate analysis of two-grating interferometer
[in Chinese]

In this paper the two- grating interferometer is analysized by means of nonapproximation. It is shown that when the number and the contrast of fringes from the interferometer are not limited by the coherence of its illuminating light, it is also not influenced by the position in space of the light source and is still capable of yielding equal spacing straight fringe pattern. The general conditions are derived under which the temporal or/and spatial coherence of illumination has no influence on the fringe patterns. Further, the effect on the interferometer due to the mismatch of these conditions is discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 2 179 (1993)
Giga watts Nd: glass laser system with PTM Q-switching
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The characteristics of a giga watts Nd: glass laser system with PTM Q-switching, the optical path scheme and its laser output performances are reported in this paper.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 2 175 (1993)
One step panoramic rainbow hologram with two concave mirrors
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

One-step panoramic holography is presented. Two concave mirrors are used in imaging system to record the rainbow hologram with 360°viewing angle on a plane holographic plate. Compared with the two-step method, the prominent property of this method is without the processes of accurate conjugate reconstruction and precise registration.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 12 1149 (1993)
Observation high power laser induced damage process by scattering
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

High power laser induced damage process is observed by scattering. Features of scattering change after sample damaged, and extrapolating damage threshold, scatter change versus laser damage morphology are described. Moreover, the laser damage accumulation effect is studied.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 12 1144 (1993)
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 11 1055 (1993)
Using space filter to improve light pipe uniformizer
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

This paper describes a technique of using space filter in the light pipe uniformizer. With this filter, the uniformity of illumination of light pipe can be improved. Some parameters of the space filter are calculated and experimental results with it is given.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 11 1052 (1993)
The discussion of chromatism and resolving power about the orthogonal cylindrical lenses holography
[in Chinese], and [in Chinese]

This paper discussed the achromatic region, resolving power, aberration and applied range etc in orthogonal cylindrical lenses holography.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 11 1049 (1993)
Dynamics of reverse saturable absorption in copper phthalocyanine
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

In this paper, we have studied the dynamic of reverse saturable absorption in copper phthalocyanine (CuPc) using the rate equation theory. The experimental demostration is given by using Q-switched YAG laser and CuPc solution. The absorption cross-section of 2.6×10-17 cm2 of triplet excited state is obtained by using thereotical simulation.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 11 1045 (1993)
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 10 960 (1993)
Microstructure analysis of thin films deposited by ractive ion plating
[in Chinese], [in Chinese], and [in Chinese]

There are distinct differences in microstructure between thin films deposited by reactive evaporation and by reactive ion plating. Cross sections of TiO2 single layer thin films and TiO2/ SiO2 multilayer stacks deposited by reactive ion plating have been investigated by transmission electron microscopy; analyses of TiO2 thin films by Raman spectroscopy and by RBS is prestented in this paper.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 10 956 (1993)
The subpixel interpolation accuracy of image spots with array detectors
[in Chinese], and [in Chinese]

Using interpolation technique it is possible to determine the image spots position with subpixel accuracy. After a brief introduction to several common used interpolation algorithms, their algorithm errors are investigated based on a Gaussian image spot model. By correcting the algothm error an even higher accuracy can be achieved. Above analyses are well verified by our experiments.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 10 952 (1993)
Real-time intensity imaging for CO2laser heterodyne receive
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The real-time intensity imaging of a CO2 laser heterodyne receiving system with an acousto-optical modulator is made for a static target in the laboratory. The image displayed by pseudocolor of four color grades is the pix of 128× 98, and the field of view is 7°×5°.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 10 949 (1993)
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 1 96 (1993)
[in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 1 95 (1993)
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 1 93 (1993)
The Raman Spectra of Bovine Serum Albumin in Aqueous Solution
[in Chinese], [in Chinese], and [in Chinese]

The Raman spectra of BSA in 5% aqueous solution extracted by nitrobenzene have been studied. The amide I band appears at 1 651 cm-1,amide Ⅲ band appears at 1 292 and 1242 cm-1. The characteristic Raman bands of the tyrosine residue are at 856、828 and 643 cm-1. The band of the s-s bond is at 522 cm-1. All the characteristic Raman bands of mis protein peptide prove that its structure consists of a- helical and random- coil. The tyrosine residue is "exposed" and the conformation of the carbon atoms in the disulfide bridge C-C-S-S-C-C is trans-gauche-gauche.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 1 89 (1993)
Calculating the birefringence of an elliptical inner cladding fiber by rectangular waveguide approach
[in Chinese], and [in Chinese]

In this paper, we presented a rectangular waveguide method to calculate the birefringence of an elliptical inner caldding single mode fiber. The fiber is approximated by a rectangular waveguide, then Marcatili and fective ndex ethod were applied respectively to calculate the birefringence caused by the elliptical clading. Numerical example was given and calculated results were compared with that obtained by plane wave approximation, modified coupled mode theory and perturbation method as well as exact values by solving the eigen value equation. It is shown that rectangular waveguide method is not only accurate but simple.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 1 86 (1993)
Studies on mode in a CuBr laser with compound resonators
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The phenomena of longitudinal mode quenching in a CuBr laser with two types of multiple-mirror compound resonators are reported. The multiple mode-locking pulse trains at a repetition rate equal to a multiple of the fundamental longitudinal mode spacing have been obtained. The highest repetition rate is up to 440 MHz. The experimental results indicate that the mulptiple mode-locking pulses at high and wide-range tunable repetition rate in CuBr laser can be generated by adjusting the structure parameters of the compound resonators, without shortening the length of the active medium.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 1 81 (1993)
Thermal fixing technique of Ti-diffused LiNbO_3 waveguide characteristics
[in Chinese], and [in Chinese]

There is a characteristics drift caused by the photorefractive effect in Ti-diffused LiNbO3 waveguides. The drift will result in severe problems to the devices in pratical use, especially to that based on optical coherence principles. Experimental results about thermal fixing technique of waveguide characteristics are presented in this paper. It is derived from our experiment that H+ ions do not play an important role in thermal fixing processing.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 1 76 (1993)
Absorption and fluorescence spectral study of Fullerence-60 and Fullerene-70
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

We have measured the absorption and fluorescence spectra from the solution of the mixture of C60 and C70 in toluene. The SHG output from a Q-switched YAG laser was used as excitation source. Two Fluorescence peaks were observed at circa 670nm and 695nm, which may originate from C70 molecules.

Acta Optica Sinica
Jan. 01, 1900, Vol. 13 Issue 1 73 (1993)
Investigation of cavity length modulation and dynamical parameter measurement for a CO2laser
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

In this paper, the small-signal response of a CO2 laser to cavity length modulation has been investigated. The results show Satisfactory agreement between theor etical and experimental studies on the effect of modulation of dynamical parameters. In this paper, the multi-level theoretical model is used to a typical CO2 laser. The dynamical parpameters of the laSer are precisely determined by fitting this theory with the experimentally measured curves.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 9 859 (1992)
Transient response of amorphous CdSe and glow-discharge amorphous Si to mode-locked laser pulses
[in Chinese], [in Chinese], and [in Chinese]

This paper reports the transient response of amorphous OdSe and glow-dicharge amorphous Silicon to ultrashort pulses generated by a colliding pulse mode-locked Nd:YAG laser. The Photocurrent relaxation is analysed with the model of extended-state transport controlled by multiple trapping.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 9 855 (1992)
Above-threshold-ionization of atom under intense laser field with realistic pulse shape
[in Chinese], and [in Chinese]

Based on the results in previous paper, we further discussed the above-threshold lonzation (ATI) of atom under intnse laser field with realistic pulse shape. Affter considering the influence of initical ionization time, it is more clear that the red shift and brodening of ATI peaks appear as the laser pulse width changes from long to short regime.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 9 850 (1992)
Investigation of surface plasmons decay using photoacoustic method
[in Chinese], and [in Chinese]

Photoacoustic (PA) observation of the decay channels of surface plasmons wag made on the plasmong excited by the attenuated total reflection (ATE). Both in the interfaces of Ag-air and CaF2-Ag-air, ATR and PA spectrum were measured at the game time. The results show that it is possible to determine the radiative and non-radiative decay quantatively by comparing measurements taken with transparent and blackened cavities.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 8 764 (1992)
Experimental study of Li-like calcium and potassium ion X-ray lasers
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 7 671 (1992)
All-fiber frequency shifter using LiNbO3SAW device
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

An all-fiber frequency shifter operating at 10.7MHz is described. The device was based on a SAW structure using interdigital transduser on LiNbO3 substrate. A coupling efficiency of 35 % has been achieved by using a 1.5W electrical drive power.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 7 668 (1992)
Generation of ultra-high intensity laser using backward scattering compressor
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Combination of backward Brillouin scattering and grating compressor has made possible the production of extremely bright laser sources. The first step towards the realization of such a source is the development of small size laser system. Using this suggestion, 100 times pulse compression of an 5 ns initial puls down to 40 ps ia obtained.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 7 664 (1992)
Automatic analysis of holographic interference photo-carrier fringe patterns
[in Chinese], and [in Chinese]

The automatic analysis of holographic interference photocarrier fringe patterns has been realized by using orthogonal coherent phase detection methed. The edge effects of analyzing the fring patterns is discussed, and a exptrapolation algorithm suited for microcomputer processing has been proposed. Finally, the analysis results of the fringe patterns are shown in this paper.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 7 660 (1992)
Measurements of refractive indices and double-frequency coefficients of KIO3single crystal
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The principal refractive indices and double-frequency coefficients of KIO3 single crystal have been measured for the first time. The measured recults are given in this paper.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 7 657 (1992)
Optical parametric generation with high conversion efficiency
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Using a 6.5×9×20 (length) mm KTP crystal, picosecond pulses were obtained with tunable range of 625nm-3575nm, maximum energy conversion effioienoy of -30 %, and maximum peak power of 34MW.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 6 575 (1992)
A study of measurement of nonlinear refractive index and time resolution for pyrylium-doped polymer films
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

In this letter we report the nonlinear property of pyrylium-doped superpolymer studied by degenerate four-wave mixing (DFWM). The nonlinear susceptibility x(3) of pyrylium-doped polymer is 3×10-10 e.s.u.. The time resolution curve formed by the decay of phase conjugate reflection as a function of the delay of the backward pump pulse in the counterpropagating DFWM scheme was observed, and the relaxation time is 30 ps. The electronic and brientational mechanisms are discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 6 572 (1992)
[in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 6 570 (1992)
Interferometric visualization and image processing of explosive flow field and combustion field of initiating agent
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

In the paper, the experiment results of time-serial interferograms of explosive flow field and initial combustion process are presented which are produced by using pulsed YAG laser to detonate initiating agent and obtained with timeserial interferometry. On this basis, a method of fringes curve detecting and the function of double cubic many-knot interpolating splines are used to extract the wave-front of shock wave. With the algorithm of serial wave-front registering the propagation velocity of shock wave is calculated quantitatively. At the same time, the distribution of temperature with the change of time in the process of initiating agent combustion is calculated quantitatively also.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 6 565 (1992)
Fast optical bistability in multiple waveguide coated with copper phthalocyanine LB films
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The 34 layers tapCuPo, the copper tera-4- ( 2.4-ditert-ampylphenoxy) phtha-locyanine, were deposited by the LB technique on the optical glass waveguide of K+ ion-exchange, and a four-layer dielectric waveguide with LB films cladding is formed. The 532 nm line from a YAG laser is used as a light source. The input light with pulse width of 250 ps is coupled into the optical waveguide by a glass prism, and then is passed through the regiod coated with the LB films. In the experiment,a fast optical bistability with the switching off time to 24 ps has been demonstrated.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 6 562 (1992)
Optical properties of chalcedony
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The analysis of the composition, construction, spectrum of transmittance and depolarization ability are made on a chalcedony sample. It reaches a conclusion that the material in a very good choice for depolarization windows of the detecters used in ultra-violet, visible and near-infrared spectra regions.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 5 476 (1992)
Ion-beam sputtering deposition of oxide coatings
[in Chinese], [in Chinese], and [in Chinese]

TiO2 and ZrO2 thin films were deposited by ion-beam sputtering. Their refractive indices, optical absorption and laser-induced damage thresholds are investigated. The optical absorption of the coatings are decreased obviously.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 5 473 (1992)
Grating optical bistability
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

In this paper, a grating optical bistable device is described. Changing the relative displacement between two symmetrical gratings, a periodic modulation of the light intensity is realized, Taking such a system as the transmission part and using He-Ne laser and white light, we have performed the optical bistable experiment. The experimental results are in good agreement with theoretical analyses.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 5 470 (1992)
Computer-Generated Holograms change the wavefront and mode of lasers
[in Chinese], and [in Chinese]

Taking that elliptical Gaussian beam change into circular symmetrial Gaussian beam as an example, this paper gives the theory and method using Computer-Generated Holograms to change the wavefront and mode of lasers, and deduces the equation of Computer-Generated Holograms. The Computer-Generated Holograms are made. Experiment results are presented.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 5 466 (1992)
Theoretical analysis of crystal clad fifcer-optic polarizer
[in Chinese]

Theoretical analysis of crystal clad fiber-optic polarizer is presented in this paper. At first, the anisotropic refractve indices of potassium pentaborate at long wavelength region were determined. Then extinction ratio variations with the parameters of single mode fiber and crystal were calculated for the polarizer with only one side crystal clad by using planar dielectric waveguide model, and the whole crystal clad polarizer by using W fiber model, The comparison and the discussion of these two types of crystal clad fiber-optic polarizer have been made.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 5 462 (1992)
Resonance enhanced stimulated four-photon mixing in Er3+doped silica fibers
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Resonance enhanced stimulated four-photon mixing and optical free induction decay have been first demonstrated in Er3+ doped silica fibers under the excitation of a 1064 nm laser. The enhancement of anti-Stokes of stimulated four-photon mixing by the excited state 4I11/2 of Er3+ has been confirmed in frequency- and time-domain.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 4 382 (1992)
Optical properties, microstructure and recording properties of phate change recording thin film GaSb prepared by RF-sputtering
[in Chinese], [in Chinese], and [in Chinese]

Amorphous GaSb thin film have been prepared by rf-magnetron sputtering. The effects of ther mally-induoed phase change of the film on its optical properties and miorostruoture have been studied systematically. It is found that amorphous GaSb thin films change to polycrgstalline state with cubic structure (α0 = 0.6095 nm) around annealing temperature 270℃, and the optical gap changs from 0.7(eV) to 0.94 (eV) after the phase change. The cauve of GaSb thin film resistance versus annealing temperature is measured by fourprobe method. And write-once recording properties and laserinduced phase change of the GaSb thin film have been studied.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 4 377 (1992)
2π quasi-periodical damping oscillation in the area-dependent population of two-I evel atoms
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A 2π quasi-periodical damping oscillation is shown in the variation in populations of two-level atoms with the time-dependent pulse area, which providers us with a rather good picture of atom behaviors under the influence of abitrary strong laser pulses.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 4 374 (1992)
Enhancement of brightness of laboratory soft X-ray lasers
[in Chinese], and [in Chinese]

A large separation "oscillator" source-travelling wave amplifier approach is suggested for attaining high power fully coherent X-ray source. Using a newly-designed aspherical lens combination, a long narrow local line can be obtained, resulting in a more uniform and narrow laser-produced plasma column. It may be a great help to raise gain-length product.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 3 284 (1992)
A study of spectral response characterization on S-25 and New S-25 photocathodes
[in Chinese]

In this paper, spectral response characterization on S-25 and New S-25 photo-cathodes are studied. Since photocathode has thicker pliotocathode thickness, higher photocathode structure parameter and spectral response cut-off wavelength, phot oca-thode sensitivity between 850 and 1000nm is improved. The improvements repres ent the superiority of New S-25 photooathode as well as a new direction of multialkali photocathodes.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 3 279 (1992)
Optical, structural and crystalline properties of GeSb2Te4thin films
[in Chinese], [in Chinese], and [in Chinese]

Phase change recording medium GeSb2Te4t hin film is prepared by RF-magnetron sputtering, Thermal annealing effects on the optical and structural properties of GeSb2Te4 thin films have been studied systematically. Thermal-inducedcrystalline property of amorphous GeSb2Te4 thin film has also been studied.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 3 274 (1992)
Separation of multiple scattering and its numerical simulation
[in Chinese]

An improved notion of calculation of multiple scattering based on the method of sucoesive singular scattering and a theorem are proposed. The results of simplified numerical simulation are in good agreement with the published experimental data.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 3 269 (1992)
A type of 10.6 μm light isolator in common transmitter/receiver antenna
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Light isolators in common transmitter/receiver antenna coherent laser radars is discussed in this paper. The characteristics of quarter waveplate and Fresnel rhomb are analysed, and the quarter retarders of Ge crystal are designed and produced. The rhomb has been used in the CO2 laser heterodyne detection system, and the transfer efficiency is more than 93%.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 3 265 (1992)
Experiment on frequency up-conversion in Er3+doped silica fibers
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Frequeney up-conversion in Er3+ doped silica fibers pumped by a CW 1064 nm laser has been first demonstrated. The visible fluorescence spectra of Er3+/GeO2/SiO2 and Er3+/Al2O3/GeO2/SiO2 optical fibers were measured. Two-photon absorption and excited-state-absorption of Er3+ ions are proposed to account for the experimental observation.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 3 261 (1992)
The overtone vibration spectrum of water vapor by using an AlGaAs diode laser
[in Chinese], [in Chinese], and [in Chinese]

26 absorption lines of water vapor in vibration-rotation band have beoen bser-ved by using an AlGaAs diode laser around 822.6-823.2 nm. The minimum absorption coefficient α-3 ×10-6 cm-1 and the SNR-60 (for α-1×10-4 cm-1) have been detected, A pressure broadening coefficient of 0.128 MHz/Pa was measured.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 3 256 (1992)
A new type of fiber-optic interferometer with high sensitivity and common mode compensation
[in Chinese]

A new type of fiber-optic interferometer is proposed and analysised. Based on Maoh-Zehnder interferometer, this novel fiber-optic interferometer offers higher sensitivity, together with the unique capability of compensation for optic source's wavelength and enviromental fluctuations by appropriate adjustment of its two phase.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 2 188 (1992)
Technique of projection correlation for fingerprinr/character identification
[in Chinese], and [in Chinese]

By using the 1-D projection correlation theory of 2-D correlation, the fingerprint and character field are identified repidly and effectively. The experiment, results are in good agreement with theory. Finally, the projection technique for idntifioation are discussed in detail.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 2 183 (1992)
Temparal diffraction integration of optical system and its applications
[in Chinese], and [in Chinese]

The temporal diffraction integration in terms of temparal ABCD matrix element is introduced in an optical system. This integration is used to discuss the Gaussian pulse propagation in dispersive medium, and to show the time-imaging in a linear dispersive medium and square pulse shaping for optical fiber.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 2 179 (1992)
[in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 12 1152 (1992)
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 12 1151 (1992)
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 12 1149 (1992)
Study on polarization effect of optical system
[in Chinese], [in Chinese], and [in Chinese]

Transformation of the degree of polarization under the action of a nondepola-rizing system is analysed. We find that the degree of polarization may be reduced in gome nonpolarizing systems and it does not agree with the belief before.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 12 1145 (1992)
Investigation of all fibre laser Doppler veloclmetry
[in Chinese]

A laser Doppler velocineter system in which ordinary single-mode eptical fibre is used to form the all optical paths is described. The velocity direction sensing is performed by an acoustic-optic frequency shifter using ordinary single-mode fibre. Single-mode fibre polarisation controllers are used to provide adjustment of the polarisation State in fibre exits. This system is simple, miniature, flexible and easy to adjust because of the all fibre configuration.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 11 1053 (1992)
Study on the two-wave mixing properties of Fe:KTN crystal
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

In this paper, the two-wave mixing properties of tetragonal phase Fe doped KTN crystal are repoted for the first time. A gain coefficient of 7.3cm-1 and diffraction efficiency of 42% were measured. The response time is 2.8 seconds. The Sign of the dominant oharge carriers is determined and some other parameters are calculated.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 11 1049 (1992)
Light scattering of polyethylens spherulites with concentric-circle
[in Chinese], and [in Chinese]

In this paper, the light scattering patterns of polyethylene spherulitea with concentric-circle extinction are examined by wide-angle laser scattering instrument. Based on the model of effective dipole moment and by moans of Fourier transform and diffraction grating principle, the causes of pattern formation are analysed and the twisted phenomena of lamellae are further discussed. The theoretical analysis is in agreement with the experimental result.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 10 956 (1992)
Lasing properties of a GGG crystal slab laser
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The laging properties of a 6×16×84 mm GGG crystal slab were measured and its thermal lensing effect was investigated under high power pumping.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 10 953 (1992)
Study of laser frequency stabilization with external Doppler frequency modulation
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

By utilizing an external Doppler dither modulation scheme, the frequency of the CO2 laser 10P(16) and 10P(18) lines are locked at the centers of the saturated absorption lines of SF6 molecules in an external absorption cell. The locked laser has a frequency fluctuations of some 7 kHz. The looked laser output has neither parasitic frequency modulation nor parasitic amplitude modulation. The stabilized frquency is independent of laser operating characteristics.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 10 950 (1992)
Observation and research of new Raman spectra characterizing nanocrystalline materials
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

We present the Eaman spectra of nanocrysttalline materials of ZrO2 and SnO2 for various particle sizes. After comparative observation and analysis, we discover and study the new spectra characterized by nanocrystalline materials.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 10 946 (1992)
Phase -stepping stoboscopic holographic interferometry
[in Chinese], and [in Chinese]

Phase-stepping technique is applied to stroboscopic holographic interferometry to extract quantitative results of vibration objects. The effect of different ratio of the pulse duration to the period of the vibration is analysed, and experimental demonstrations are presented.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 1 92 (1992)
Absorption coefficent of multialkali photocathodes
[in Chinese], [in Chinese], and [in Chinese]

The absorption, coefficient experience formula of multialkali photocathodes (Na2KSb(Cs)) is given in this paper. The theoretical curves of coefficient calculated by the formula show good agreement with experimental results in the visible and near infrared "regions. The absorption coefficient of multialkali photocathodes on near absorption edge is derived by quantum mechanics. Quantum yield difference between S-20 and LEP is explained.

Acta Optica Sinica
Jan. 01, 1900, Vol. 12 Issue 1 87 (1992)
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 11 Issue 9 864 (1991)
[in Chinese], [in Chinese], and [in Chinese]

Acta Optica Sinica
Jan. 01, 1900, Vol. 11 Issue 9 863 (1991)
Making of hard alloy WC-TiC-Co and study of its mechanism
[in Chinese], and [in Chinese]

This article presents a method of making hard alloy WC-TiC-Co on the No.45 steel surface by using high power laser beam. The microstructrue and performance of the alloyed layer are observed, examined and analyzed, and the mechanism of forming hard alloy is studied. The results indicate that it is very successful to improve the properties of the metal material's surface with this method.

Acta Optica Sinica
Jan. 01, 1900, Vol. 11 Issue 9 858 (1991)
The VUV spectrum of five-time ionized titanium TiVI
[in Chinese], and [in Chinese]

The spectrum of five-time ionized titanium emitted from a three-electrode vacuum spark has been observed using a 1-m normal incidence speotrograph. We have observed 157 new lines of TiVI in the region from 24 to 200nm. According to the newly identified lines of TiVI we have found 11 new enegy levels and revised 5 doubtful energy level valuse.

Acta Optica Sinica
Jan. 01, 1900, Vol. 11 Issue 9 853 (1991)
Theoretical Calculation of Energy Levels and Soft X-ray Spectra for Na-like ions from Copper to molybdenum
[in Chinese], [in Chinese], and [in Chinese]

The energy levels of Na-like ions from Copper to Molybdenum are reported. The transition wavelengths of 5g-4f, 5f-4d, 6g-4f, 6f-4d are given as well as the oscillator strengths. These transitions are of potential interest for X-ray laser. The results indicate that the 6f-4d transition of Se ions, the 6g-4f transition of Br ions, the 5f-4d transition of Zr ions, the 5g-4f transition of Nb ions are all in the range of the "Water "Window".

Acta Optica Sinica
Jan. 01, 1900, Vol. 11 Issue 9 848 (1991)
Single transverse mode narrow bandwidth pulsed tunable dye laser with hollow circular dielectric waveguide
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

This paper presents a novel widely tunable, pulsed dye laser with single transverse mode narrow bandwidth which can be constructed by using a grazing-inoidenoe grating in eonjustion with a hollow circular dielectric waveguide. The experimental results show that the single transverse mode narrow bandwidth laser output can be obtained while maintaining a high lasing efficiency. The mechanism of the improvement is also discussed in this paper.

Acta Optica Sinica
Jan. 01, 1900, Vol. 11 Issue 9 844 (1991)
Folded longitudinal acoustic phonon modes in ZnS-ZnSe strained-layer superlattice
[in Chinese], [in Chinese], and [in Chinese]

The Raman spectrum of folded longitudinal acoustic phonon modes of ZnS-ZnSe strained-layer superlattice have been reported. In the region 10~90cm-1, three doublets were observed at room temperature.

Acta Optica Sinica
Jan. 01, 1900, Vol. 11 Issue 8 767 (1991)
1.08 μm superradiation in Nd-doped silica fiber
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Pumped by 514.5 nm Ar ion laser, superfluorescence was observed in a 3 m Nd-doped silica fiber. The maximum output power is 6 mW with the emission linewidth-of 3 nm. A good agreement is found between experimental; data and theoretical fits.

Acta Optica Sinica
Jan. 01, 1900, Vol. 11 Issue 8 764 (1991)
Polarization method of moving interference fringes
[in Chinese], and [in Chinese]

Based on the theoretical analysis of two elliptically polarized light fields, the features of two elliptically polarized light fields which orthogonalized each other (levorotation and dextroroyation) and a circular polarization and a linear polarization light field are disused. Polarization method for moving interference fringes is introduced.

Acta Optica Sinica
Jan. 01, 1900, Vol. 11 Issue 8 761 (1991)
Study on the number of calibrating wavelengths for calibration of optical wedge space
[in Chinese], and [in Chinese]

The calibration of optical wedge space in Fizeau laser wavemeter is the precondition for the measuring laser wavelegth accurately. The number of calibrating wavelengths for the calibration of optical wedge space is studied in this paper. The analysing results show that the number of the calibrating wavelengths mainly depends on the selection style for the calibrating wavelengths and the error range of the optical wedge space.

Acta Optica Sinica
Jan. 01, 1900, Vol. 11 Issue 8 755 (1991)
The design of KNSBN self-pumped conjugators
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The prioiple and basic considerations of the design of barium strontium potassium sodium niobate (KNSBN) self-pumped phase conjugators are given in this paper. The corresponding device was designed and its oharateristica were studied.

Acta Optica Sinica
Jan. 01, 1900, Vol. 11 Issue 6 573 (1991)
Optical perfect shuffle using CGH element
[in Chinese], and [in Chinese]

In this paper, we describe a new method using computer generatal holograph element (CGH) to complete two-dimensional optical perfect shuffle, Experimental result shows that it is feasible and effective. The mothod can be extended to other transformnet work.

Acta Optica Sinica
Jan. 01, 1900, Vol. 11 Issue 5 477 (1991)
Fluorescence lifetime measurement of haematoporphyrinand lactoflavin
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

In our experiment described in this paper, the single pulse of the picosecond laser (λ=0.527 μ) from bhe output of a frequency-doubled mode-locked phosphate Nd glass laser at λ=1.054同μm was used as the exciting light source. The lifetimes of the excited singlet states S1 of the organic biological macromolecules haema-toporphyrin and lactoflavin were measured with streak camera. The quenching effect of oxygen molecules on the lifetimes was discussed preliminarily.

Acta Optica Sinica
Jan. 01, 1900, Vol. 11 Issue 4 381 (1991)
Accurate holographic interf erometry-application of phase stepping technique
[in Chinese], and [in Chinese]

A system for accurate phase determination using two-referenoe-beam, duble-exposure holographic interferemtry and phase-stepping technique is described. It calculates the interference phase pointwise with repeatability better than 2%, and takes less than 2 min for a 256×256×8 bit image.

Acta Optica Sinica
Jan. 01, 1900, Vol. 11 Issue 4 376 (1991)
A novel transverse mode control resonator for pulsed Nd3+:YAG laser
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

It is presented in this letter that a novel transverse mode control resonator (TMCR) can be constructed by using a stable resonator in oonjuction with a suitable hollow circular dielectric waveguide. In comparison with a TMCR with a pinhole, the energy conversion of the pump to TEM00 mode output is high and the beam fan field divergence is small. The mechanism of the novel TMCR is discussed and analysed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 11 Issue 3 285 (1991)
Second harmonic generation using an active nonlinear medium Nd:MgO:LiNbO3
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Self-freqency doubled laser was demonstrated by using Nd: MgO:LiNbO3 as active and nonlinaar optical medium. Pumped by a small Xe flash-lamp, the second harmonic wave (547 nm) was generatad at room-temperature with 4.8J threshold and 400μJ/shot maximum output. The tamparature range of operation is over 20℃~45℃ and photorefractive damage has not yet observed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 11 Issue 3 283 (1991)
Analysis of grating imaging based on coherent theory
[in Chinese]

The intensity distribution and the allowable locations of both object and image in grating imaging are derived from coherent theory. A group of experimental photographs with different parameters and a group of diagrams drawn by the aid of the computer are given in this paper.

Acta Optica Sinica
Jan. 01, 1900, Vol. 11 Issue 3 278 (1991)
Two-speckle-patterns phase-shifting digital interferometry
[in Chinese], and [in Chinese]

A digital speckle pattern interferometry system for automatic measurement of deformations of a diffuse object is presented by using phase-stepping and digital signal processing technique. Computer is utilized to take data and calculate phase without an intermediate recording step. Phase frings are produced instead of speckle correlation frings. Noise data points caused by randomness of the speckle are removed by digital signal processing. Two experimental results for the measurement of in-plane and off-plane deformations are presented.

Acta Optica Sinica
Jan. 01, 1900, Vol. 11 Issue 3 273 (1991)
Four-wave mixing in GaAs crystal
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

We have observed infrared conjugate pulses in undoped GaAs crystal by using degenerate four-wave mixing (DFWM) pumped by 1.06μm mode-looked Nd:YAG laser. Main properties of these pulses and enhancement of the gain are discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 11 Issue 3 269 (1991)
Space-resolved spectroscopy studies of excimer laser ablation of Y-Ba-Cu-O superconducting target
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Space-resolved luminescence spectra of excimer laser ablation of high Tc Y-Ba -Cu-O superconducting target was studied with WP4-optioal multichannel analyzer. In the vicinity region of the target surface (d<0.35mm), a wide continuum spectrum with salf-absorption lines due to the electronic transition from the ground states of Y, Ba and Y+, Ba+ was observed. The excited state emission spectrum lines of atoms, ions and moleoulae were detected only at the distance larger than 0.35mm. These experiment results support the dynamic explanation of explosion and ejecting molecular cluster or solid fragments on laser ablation.

Acta Optica Sinica
Jan. 01, 1900, Vol. 11 Issue 2 189 (1991)
Discussion of calculating method for theoretical limit of laser linewidth
[in Chinese], and [in Chinese]

This paper discusses the calculating method for theoretical limit of laser linewidth in the single mode laser cavity in which the distribution of light intensity is nonuniform. Authors analyse the revision factor of linewidth for two different models of light intensity distribution.

Acta Optica Sinica
Jan. 01, 1900, Vol. 11 Issue 2 184 (1991)
Experimental investigation on saturated galnof soft X-ray laser from Ne like Ge plasma
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Using the technique of "Mulxi-Target cascade", an output of near saturated gain of soft X-ray laser from Ne-like Ge plasme was abtnined.

Acta Optica Sinica
Jan. 01, 1900, Vol. 11 Issue 12 1135 (1991)
SRS in quasi-monomode germanium doped silica-core fiber
[in Chinese], [in Chinese], and [in Chinese]

The experiments of SRS in quasi-monomode germanium-doped silica-core fiber are reported. The phenomena of competition between Raman modes and order-jump of SRS are observed. The competition between SRS modes is discussed in detail.

Acta Optica Sinica
Jan. 01, 1900, Vol. 11 Issue 12 1131 (1991)
Determination of optical constants for LB films with surface-plasma-wave technique
[in Chinese], and [in Chinese]

The surface-plasma-wave technique is a very sensitive way used for determining the optical constants of ultra-thin films. In this paper we propose a new method to determine the dieleotrical coefficient and thickness of Langmuir-Blodgete film unambiguously by measuring the angle spectrum of minimum reflectivity with respect to thickness of air gap in Otto's coupling system. Experimental results for arachidic acid LB films with different number of molecular layers are presented.

Acta Optica Sinica
Jan. 01, 1900, Vol. 11 Issue 12 1125 (1991)
Cu-doped KNSBN high reflectivity self-pumped phase conjugate mirrors
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

We have demonstrated the self-pumped phase Conjugate mirrors of Cu-doped KNSBN crystals. The phase conjugate reflectivity reaches as high as 65% for the crystal with Cu-doped 0.04wt%. The phase conjugate reflectivity and its response time were also measured as a function of the Argon-ion laser wavelengths.

Acta Optica Sinica
Jan. 01, 1900, Vol. 11 Issue 11 1055 (1991)
Nogelatin dichromated holographic recording material and its real-time property
[in Chinese], [in Chinese], and [in Chinese]

In this paper, the real-time effect and the primary property of nongelatin diohromated (NGD) holographic recording material are described briefly. The realtime diffraction efficiency (ETED) of up to 25 % at ±1 level in plane grating has been obtained in the experiment.

Acta Optica Sinica
Jan. 01, 1900, Vol. 11 Issue 10 956 (1991)
Laser induced damage to optical thin films of different coating designs
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

In this, paper, investigation of laser induced damage to polarizing coatings and 1.06μm high-reflection coatings is pre-sented. The relationship between damage thresholds and coating designs has been studied. The experimental results have been an-alysed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 11 Issue 1 93 (1991)
Fast and high accuracy processing technique of speckle photography fringes
[in Chinese], [in Chinese], and [in Chinese]

A fast and high accuracy technique, homomorphio-threshold filtering of speckle photography fringes is presented in this paper. It can be used to continuously process the speckle photography fringe with high-speed, pointwise and high-precision. So the speckle photography fringe spacing and orientation can be-recongnized effect-ively.

Acta Optica Sinica
Jan. 01, 1900, Vol. 11 Issue 1 88 (1991)
38 fs light pulses generated from a synchronously pumped dye laser
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

We have demonstrated that optical pulses as short as 38fs can be successfully generated from a simple linear-cavity dye laser. The laser consists of a six-mirror cavity with two dye jets (a gain jet with Rh 6G and a saturable absorber jet with DODCI) and a pair of prism as group-velocity disperesion compensator, and is synchronously pumped by the frequency-doubled output of a CW mode-locked Nd: YAG laser. The average output power is 20 mW at a reptition rate of 100 MHz.

Acta Optica Sinica
Jan. 01, 1900, Vol. 11 Issue 1 84 (1991)
Diffraction spectrum of reflection hologram
[in Chinese], [in Chinese], and [in Chinese]

The experiments has shown that the spectrum of reflection hologram presents obvious non-symmetry, and is accompanied with a series of sub-peaks. In this paper, the experimental results under varied condifious are reported and the characteristics of the spectrum are analyzed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 11 Issue 1 78 (1991)
Beam-expander prism used in laser gyroscope signal detection
[in Chinese], [in Chinese], and [in Chinese]

It is predicated both theoretically and experimentally that beam-expander prism utilized in the signal detection of lareor gyroscope can effectively enhance the signal to-noise ratio of beat signal received by detectors.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 9 862 (1990)
3 Dimensional spectro-gonioreflectometer
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Construction, controlling, and data processing system of a 3 dimensional spectro-gonioreflectometer developed at National Institute of Metrology (NIM) are introduced in this paper. Radiance uniformity of a spherical radiator and photometric nonline-arity of measuring system as well as wavelength accuracy and stray radiation of the monochromator are tested. Reflected radiance distribution curves of a mat ceramic plate and a Halon pressed powder plate have been measured. Some inportant applications of the gonioreflectometor to colorimetry and spectro-photometry are discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 9 857 (1990)
Eye protection against laser with holographic optical elements
[in Chinese], [in Chinese], and [in Chinese]

The reflection holographic filter has ideal filtering property, and can be well used as a kind of elements for eye protection against laser. In this paper, the wavelength selectivity and the angle selectivity of holographic filters are analyzed. The power density threshold of the medium is tested and some practical problems are discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 9 851 (1990)
Analyses of rinbow holography with the line-element hologram
[in Chinese], [in Chinese], and [in Chinese]

Based on the inherent line-element hologram of rainbow holography, this paper presents the illustration of the imaging mechanism of rainbow holography by no means of the traditional concept of slit images. The relationship between the width of line-element hologram and the minimum resolved distance as well as the stereo limit of the reconstructed image are discussed in detail. Characteristics of the line-element holograms and their effects on several typical rainbow holograms are illustrated and a new approach of observing the reconstructed image without the real slit image is proposed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 9 845 (1990)
Evolution of the multiphoton Jaynes-Commings model
[in Chinese], and [in Chinese]

In this paper, the general evolution laws of the multiphoton Jaynes-Commings model which is initially in an arbitray state have been investigated. The quantum statistical properties of the two-photon Jaynes-Commings model for a two-level atom interaction with a coherent light field, as example, have been discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 9 837 (1990)
Optical measurement of the Fourier phase
[in Chinese], and [in Chinese]

On the basis of diffraction property of a grating in the Fourier optical system, the real part and imaginary part in the Fourier spectrum of object could be obtained, and the Fourier phase could be measured. The experimental results regarding to the optical measurement of Fourier phase for 1-D real object are presented and discussed in this paper.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 8 765 (1990)
Experimental research on laser amplification in Er+——doped fiber
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

An experiment on laser amplification using a home made Er+——doped fiber hag been demostrated. A laser amplification at 1.52μm wavelength has been observed with a gain of more than 10 dB when Ar+-laser pump is applied. Some experimental data on Er+-doped fiber and its laser amplifier are given in this paper.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 7 668 (1990)
An effective method for measuring high reflectivity (or transmissivity) of optical components
[in Chinese], and [in Chinese]

An effective method for measuring high reflectivity (HR) of laser mirrors and high transmissivity of optical components with antireflective (AR) coats is described in this paper. The features of the method are that n-components with HR or AR ooats are measured at same time, and the measuring error is 1/n of the normal way. Measurements of a group of laser mirrors with HR coats and a group of thin disk with AR coats show the acceptability of the method.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 7 664 (1990)
Depression of background noise in reflection holographic filters
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Compared to the conventional in terference filter, the main disadvantage of holographic filter is its higher background noise. In this paper, a method using slanted fringes is introduced, with which the background noise of a reflection holographic filter can be depressed greatly.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 7 661 (1990)
A new method for recording colour rainbow image plane hologram
[in Chinese], [in Chinese], and [in Chinese]

A new method for recording colour hologram is proposed is this paper. Using liquid crystal ligh valve (LCLV) and a monohromatio laser. LOLV is a device with which incohernt light image can be translated into coherent light image. Three holograms corresponding to, three primary colour are recorded respectively on the same ailTer holide plate using a laser of 6328 A This hologram can reconstruote original colour image using whste light.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 7 656 (1990)
Propagation properties of a pair of soliton pulses in a fiber
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

It is pointed ont that the Split-step Fourier Method and the Propagating-beam Method are equivalent, and namerically calculated by the method that a pair of soliton pulses propagate in a fiber with bhe initial equal changeable amplitudes-Our results show that the interaction between solitons can be much greately reduced by raising their amplitudes.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 7 651 (1990)
Liquid FT-IR photoacoustic detector for elimination of water-vapor interference
[in Chinese], and [in Chinese]

A liquid photoacoustic detector suitable to Fourier transform infrared (FT-IR) spectrometer with a condenser microphone as coupling unit is described in this paper. The experiments with the use of this detector show that the interfering signal arising from vapor absorption can be eliminated. We also present a better method for measuring FT-IE spectrum of aqueous sample in this paper.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 7 647 (1990)
Excitonic optical bistability in ZnSe/ZnS multiple quantum wells
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Optical bistability in the ZnSe/ZnS multiple quantum wells (MQWs) grown by MOCVD has been observed at 77 K for the first time with ns switching time. On the bases of the shape of hysteresis loop and photoluminescence and absorption spectrum measured, the optical bistability in the ZnSe/ZnS MQWs can be attributed to enhanced absorption effect, which originated from the collision broadening of excitonic resonance.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 7 643 (1990)
Phase conjugation by four-wave mixing of Nd:YAG lasers in Si single crystal
[in Chinese]

The phase conjugate wave has been obtained by degenerated four-wave mixing (DFWM) with silicon single crystal as the nonlinear medium using Q-switched Nd:YAG lasers. The reflectivity of the phase conjugate mirror (PCM) has been calculated from the theory of the light induced electron-hole-pair density, which produced a phase grating. Experimentally, a reflectivity of 125% of the PCM was obtained and the property of the compensation of the phase aberrations was demonstrated.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 6 570 (1990)
Optical instability in ZnS optical bistable devices
[in Chinese], [in Chinese], and [in Chinese]

In this paper we present the first observation of optical regenerative pulsation in ZnS interference filter bistable device. Condition for the device to be unstable is analysed. Simulation of the pulsation process has been carried out. The device is expected to be used as clock-pulse generator in optical digital computing experiments.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 6 565 (1990)
Experiments of real-time atmospheric turbulence compensation with adaptive optical system
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The experiments of using adaptive optical system to detect and correct the atmospheric turbulence effect in real-time along a 340 m horizontal path about 15 m above ground are reported. The results show that the image quality for point source and extended source with certain extension after corrected by adaptive optics is improved.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 6 558 (1990)
A new type of optical system in optical head for magneto-optic disk drive
[in Chinese], and [in Chinese]

This paper describes a new type of optical system in optical head for magneto-optic disk drive, expounds theoretical the basic principle for magneto-optio information read out. The system has improved the performonoe of optical system reduced optical noise, incrased efficiency of optical energy. It has been applied to the development for a prototype magneto-optio disk(51/4inches) drive and the ratio of read out signed-to-noise has been reached more them 50 dB.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 6 552 (1990)
Theoretical analysis on inhomogeneous reflection hologram
[in Chinese], [in Chinese], and [in Chinese]

A theoretical analysis on inhomogeneous reflection hologram was made in this paper. Taking account of the light absorption of recording medium the coupled wave equation consisting of two linear differential equations was transformed to a nonlinear differential equation-Riccati equation. The characteristics of the equation was analysed. From numerical solution, some new significant phenomena were discovered.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 6 545 (1990)
Circular birefringence due to geometri path of optical fibers
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Polarization rotation due to geometric path of singlemode optical fibers has been investigated. The results of theoretical and experimental studies are reported on such polarization rotation with input and output ends of fibers being non-parallel. This is, to our knowledge, the first time that this kind of research has been done.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 5 476 (1990)
Off-axis detect on approach-a new autofocusing method
[in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A new antofoeusing method called off-axis detection (OAD) method is deoeloped. It used no ether elements except a off-axis arranged quadrant detector . It has the advantages of simplicity, good reliablity, high sensitivity, better linearity and can be used in many fields, especially, in optical disk. The principle of the OAD method is described and the results of computer simulation and experiment are given.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 5 470 (1990)
How to adjust the pseudocoloring of an encoded phase-picture through the spatial filtering
[in Chinese]

A new method adjusting pgendocoloring by spatial filtering is presented and its theoretical analysis is given.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 4 382 (1990)
Experimental study of laser of FB(Ⅱ) color centers in Na KCl crystals at liquid nitrogen temperature
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A laser utilizing FB (II) centers in Na-doped KCl crystals and operating stably a-liquid N2 temperature is described. Color center crystal was pumped by the frequencyt doubled output of a Q-switched Nd:YAG laser. Laser emission wavelenghth. ranges from 2.420 to 2.542 μm. Experimental results are discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 4 378 (1990)
Additional optical path caused by yaw of moving roof mirror in composite retro-refletor system
[in Chinese], and [in Chinese]

The composite retro-reflector system plays the role of the cubic corner retro-reflector on 2-D interferometric controlled precioion workstage. But it is liable to cause considerable additional optical path when it is yawing. The formulan for calculating the additional optical path are derived and the measures to reduce the error are discussed in this paper.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 4 374 (1990)
Measurement of thermal expansion coefficients of optical thin films
[in Chinese], and [in Chinese]

Thermal expansion coefficients of optical the films can be measured by means of the combination of photothermal displacement optical team deflection technique and transverse photothermal dcffection technique. In this paper, single layers of SiO2, TiO2, ZrO2, MgF2 and ThF4 are taken as examples to show the experimental methods and results.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 4 369 (1990)
Automatic processing of holographic interferogram with intense background
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The principle of de fects inspecting in selder joints on printed circuit board (PCB) by holographic method has been described briefly in this paper. In order to processing interferogram with intense background by computer, some suitable methods have been suggested. We have accomplished image background and noise depressing, smoothing, thinning and recognition of the fringes. Satisfied rasults have been obtained.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 4 365 (1990)
Stimulated Raman scattering in CBrCl3liquid core fiber
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

11 Stokes orders of SRS were observed in CBrCl3 liquid core fiber pumped with a mode-locked and Q-switehed YAG laser at 1.06μm. Eelative peak power of pumping and Stokes pulses as well as the frequeonoy spectra of 9th, 10 th and 11 th Stokes light were measured. This kind of liquid core fiber can serve as an IR coherent light source-beyond 2μn wavelength.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 4 362 (1990)
Dependence of extinction ratio on birefringent axes rotation in polarization-maintaining fibers
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Based on a model of infinite slices imaginarily out and Jones matrix theory, an equivalent matrix is proposed for describing polarization-maintaining fibers with rotation of their birefringent axes. The influence on the extinction ratio is discussed due to birefringent axes rotation in the polarization-maintaining fibers.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 3 286 (1990)
A new device for manufacturing holographic gratings
[in Chinese]

A new device and its setting method for manufacturing holographic gratings have been demonstrated based on the principle of Lloyd mirror. The advantages of the device are of simple in optical system, high in locating accuracy of interference fringe and convenient to setting, etc. It can be used in manufacturing holographic gratings suitable for spect oscopy.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 2 189 (1990)
The physical properties of liquid surface wave grating
[in Chinese]

In this paper parallel sine waves producing on liquid suriace are acted as an ideal reflective grating. When the grating is irradiated by laser beam. (with certain wavelength and certain incident angle), the diffraction patterns are formed. The diffraction patterns characterize the physical properties of the liquid surface and gas-liquid interface.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 2 183 (1990)
The properties of Nd3+doped glass temperature and optical fibre temperature sensor
[in Chinese], and [in Chinese]

The absorption of Nd3+ doped glass is analysed on theory and indicates the reason of temperature dependent absorption of Nd3+. In experiment, the severeal kinds of probe with Nd3+ doped glass core are made. The experimental results agree with theory analysis. The results demonstrate that Nd3+ doped glass is one of superior temperature sensing material.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 2 178 (1990)
LiF crystal F+3—F2mixed color-center laser
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

A pulsed laser using F3+-F2 mixed color centers in a LiF crystal operted at room temperature is reported. The laser output wavelength ranges from 510nm to 580nm and from 640 nm to 710 nm using a LiF crystal and a pumping wavelength. The total bandwidth is 140 nm.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 2 174 (1990)
A double-pulse TEA CO2laser with adjustable pulse interval
[in Chinese], [in Chinese], and [in Chinese]

A novel transversely excited atmosphere carbon diaxide laser is described in this paper. It is constructed by common optical cavity. The device produces two pulses with adjustable time interval up to 150 μs under single excitation, which is obtained without gas flow. The design features of the construction and control circuit are presented. The experimental result and conclusion are given.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 2 168 (1990)
Measurement of ultra-low stray light in a laser Raman spectrometer
[in Chinese], [in Chinese], and [in Chinese]

The stray light measurement is a difficult problem in specifying x the technical performance of a laser Raman spectrometer. This article suggests a new method of testing ultra-low stray light in a laser spectrometer. Experimental results show that, the stray light measuring limit of the order of 10-14may be achieved.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 2 165 (1990)
Electronic speckle-pattern interferometry with polarization phase-shifting technique and it's application to deformation measurements
[in Chinese], and [in Chinese]

An E. S. P. I. with polarization phase-shifting technique for the deformation measorements of diffused surface is presented. The high stability is obtained by adopting the common-path optical phase-shifting technique. A phase map can be precisely obtained from computer image processing technique. The precise data of surface deformation are extracted directly by unwrapping technique.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 2 161 (1990)
A new approach to obtaining efficient generation of multiple illuminating beams
[in Chinese]

On the basis of image contrast reversal, a new method is described for efficiently generating multiple illuminating beams. This technique can be applied to the fabrication of array light signal sources needed by array processors or optical computers. Experimental results are presented and discussions are given.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 12 1132 (1990)
Theory of power spectrum of linear frequency-swept optical pulses
[in Chinese], and [in Chinese]

Expressions of the power spectrum of linear frequecy swept Gaussion pulses are given which are equivalent to the power spectrum of the modulated and compressed light pulses without ohirpping. The chirp ping be can determined by means of the power spectrum and the standard intensity autocorrelation.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 12 1129 (1990)
Effects of laser spatial inhomogeneity on above-threshold ionization
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

By taking into account the spatial inhomogeneity of the laser field in the essential state model theoretical prediotions well consistent with the experimental results are obtained.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 12 1125 (1990)
The experimental study on nonlinear four-frequency heterodyne detection of CO2laser
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

CO2 laser heterodyne detection is one of the promising methods for civilian and military radar. In this paper, the nonlinear four-frequency heterodyne detection have been analysed theoretically. In experiment, the nonlinear fourfrequency heterodyne detection was realized and the results obtained coincides with expected one. Square amplifier is the key element for the processing of electric signals from heterodyne detector in four-frequency system. The main principle is described and a practical device had been made used in the experiment.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 11 1052 (1990)
Single photon resonance and two-photon resonance laser enhanced ionization spectrometry of rare-earth element Europium (Eu)
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

Laser Enhanced Ionization (LEI) spectrometry of rareearth element Europium (Eu) is studied. Single photon resonance LEI spectrometry of EuI 287.779nm, EuI 287.887nm, EuI 289.254nm, Eul 280.303nm and EuI 289.383nm are detected by UV tunable laser and two photon resonance LEI speotrometry of EuI also are deteoed by visible tunable laser. The meohanism of excitation and ionization of Eu atoms are discussed. The detection limit of the element Eu is about 10 ng/ml.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 10 956 (1990)
Research of nonlinear guided-wave gratings
[in Chinese], and [in Chinese]

Fundamental concept and fabricating method of nonlinear gnided-wave periodic structure are described in this paper. Grating couplers are made on InSb and semiconductor doped glass waveguide. Nonlinear coupling effects are observed experimentally. Their practicabilities are discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 10 950 (1990)
The effect of Cl-and ZnCl4=ions on the ultrafast supercontinuum generation in water
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The spectral distributions of ultrafast supercontinuum laser from aqueous solutions of NaCl, KCl, ZnCl2 and K2ZnCl4 at several concentrations have been studied using 35-pseo laser pulse at 1.06 μm. In visible region the spectral distribution of USL from H2O is strongly affected by halides. The main features are significant increase in SRS intensity by Cl- and the effective spectral broadening due to the formation of complex anion ZnCl4=in concentrated ZnCl2 and K2ZnCl4 solutions.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 1 92 (1990)
Fringe sharpening in grating-interferometry by using pseudo-random sequence gratings
[in Chinese], and [in Chinese]

A technique of coding gratings in the grating-interferometer with pseudorandom sequences is described in this paper. Consequently, fringe sharpening is resulted. The theoretical analysis and experimental verifications are given.

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 1 88 (1990)
Squeezing phenomena in atomic coherence states
[in Chinese], and [in Chinese]

It has been shown that the squeezing behaviors in atomic coherence states are not similar to those in Glauber coherence states. A operator G(ξ) simulating the squeezing operstor S(ξ) can't be a "atomic" squeezing operator".

Acta Optica Sinica
Jan. 01, 1900, Vol. 10 Issue 1 84 (1990)
The effect of gradient term on the modes of inhomogeneous optical fiber
SU KEFENG

Rigrous analysis for weakly-guiding inhomogeneous refractive index profile optical fiber shows that, while the gradient term can be included in soalrr wave equations of longitudinal field component, it must be neglected in the transverse field equations. Specific expressions of the effect of term on TM modes are obtained, hence bhe degeneracy between TM and TE modes is eliminated and the single-mode condition is clarified.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 8 763 (1989)
A measuring method of relative spectral sensitivity distributions of photoelectric detectors
Wu JIZONG, Lu JINGHONG, and ZHANQ FENGHONG

In this paper, bhe relative gpectral sensitivity distributions [S(λ)r] of photoelectric detectors are classified and compared. On the basis of above considerations, a new method for measuring S(λ)r using the pyroeleotrio detecbor as the reference and the integrating sphere as the monoohromatio radiation receiver has been suggested and designed. Because of the advantages of system structure, guch error factors as polarization and nonuniformity of incident radiation, temperature drift of detectors and stray radiation are decreased significantly.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 8 758 (1989)
An automated method for 360 ° surface measurement of 3-D objects
SU XIANYU, CHEN XIAOXIE, and GUO LUROXG

A new method for obtaining a complete 360° reconstruction of a general 3-D object is presented. The principle, system construction, data acquisition and processing schedule, and exparimental results are described briefly.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 7 670 (1989)
0.86μm laser two-dimension-scanning imaging experimental research
WANG WEIRAN, CHEN WEIYONG, LIU HONGZNAN, and PENG LIADG

In this paper, a set of images with 0.86μm laser two dimension scanning imaging and the block diagram of imaging experimental system were presented- the range equation of the lager imaging system and the measured data of retorre, flectanoe oontrait for several different matters were given also in the paper.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 7 667 (1989)
The property of light polarization in single multimcde optrcal fiber and its effect on the image transmitted using phase cojagaticn
LIN DAN, YANG GUOGUANG, GU TIANQU, HE CHONGFAN, LI XUEMEI, and TANG YUANFENG

The polarization property of the light beam carrying an image while passing through a multimode step-index optical fiber and its effect on the quality of the image tnransmission by phase conjugation are studied in this paper. The method of filtering the noise is suggested. With this method, main part of the noise can be reduced and the image quality can be improved. Both the theoretiial analysis and esperimentat results are given, and a transmitted image with a resolution of 40 line/mm is obtained.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 7 662 (1989)
ESR study of photolytic process in six laser dyes under action of UV irradiation
FU WENBIAO, WU ZHENGLIANG, and Zhao Jinming

The property of photolysis for six kinds of laser dye-ethanol medium was studied by EST technique. Free radicals and triplet state was measured at 77 K. Finally the experimental results were discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 7 658 (1989)
A method of measuring the modulation of refractive index of phase holographic recording medium
YUN GANG, and Yu MEIWEN

A method of measuring the modulation of refractive index of a certain holographic recording medium is presented in this paper, for the purpose of more appropriately evaluating different recording mediums and different fabrication techniques.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 7 653 (1989)
Discrete Hankel transform and its application to laser shaping in high efficiency
LI YONGPING, and ZHU JIANG

Discrete zero-order Hankel transorm is developed and applicated to the design of phase units which can uniform optical fields. The results appeared to be more ideal and accurate than the two-dimensional FFT.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 6 573 (1989)
A possible way for generating sub-poissonian field
GU QIAO, and ZHANG JIYUE

A novel feature in single-mode laser is revealed. The nonolassioal field with sub-poissonian photon statistics can be induced by single-mode laser at certain pump conditions. A possible way for generating sub-poissonian field is thereby proposed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 5 478 (1989)
Spin-polarized MS-Xα calculation of the CsMnBr3 crystal
QlU Y0ANWU, and ZHU JIKANG

In this paper the electronic structures of the complex ion (MnBr6) 4- are calculated with the spin-polarized MS-Xα method under the actual crystal field of symmetry D3d of the crystal CsMnBr3. The one-electron eigenvalues and elgenfunotions and the spin polarization splittings are given. Energies of some optical transitions and the charge transfer transition are calculated based on the transition state theory. The spinorbit coupling constants are calculated with the Oase-Karplus charge parti Won method, and fine structures of the absorption spectra are disoossed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 5 473 (1989)
Measurement of femtosecond pulsewidth with interference correlation
GONG ZHENGLIE, QIAN SHURONG, ZHAN CHEN, and WANG QINQYUE

A new technique for measurement of femtosecond pulsewidth is proposed with equality-width in this paper. The positions on the up-envelope of interference correlation curve are given at which the envelops width equals FWHM of the second order intensity correlation curve. They are 3.984, 4.875 and 4.928 corresponding to pulse shape of sech2t/T, exp(-2t2/T2) and exp (-2t/T), respectively. The critical delay velocities for two kinds of correlation measurement are defined. Theoretical analysis is in good agreement with experiment. The results show that the measurement method oan enhance the resolution of correlation measurement of ultrashort pulse to a few or eyen tens times.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 5 467 (1989)
Study of electronic XOR logic Moire technique and effect of differential equiorder surfaces rotation
ZHANG HONG, LIU LIBEN, WU SHUDONG, and WANG ZIJIANG

This paper reports the Moire technique by means of digital electronic XOR logic for obtaining 3-D object contour fringes in real time. The main advantage of this method is removal of the unwanted patterns. In this method the rotation of equlorder surfaces is obtained by changing period of projection grating. Also the slope contour fringes are obtained by moving the object in lateral. The projection system by means of self-imaging Talbot effect is used. The experimental results are presented.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 5 460 (1989)
Orientational dependence of absorption and laser induced damage in wire grid polarizers
LIANG JIUQING, ZHOU GUOSHENG, MEHRDAD MOHEBI, and M. J. SOILEAN

We report in this paper the theoretical and experimental study on the relation of the absorption in wire grid polarizer with laser polarization orientation and wavelength. Measurements of absorption and laser induced damage thresholds are in good agreement with theoretical model.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 5 453 (1989)
Propagation of Gaussian Schell-Mode beams through optical system
Pu JlXIONG, and CHEN JINKAI

The formula describing propagation of second order correlation function of Gaussian-Sohell model beam via optical system has been derived based on Hugens-Fresnel diffraction integral. By introducing a parameter q similar to that of Gaussian beam, it is proved that the ABCD transformation law is satified with the q of Gaussian-Schell model beam.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 5 447 (1989)
Optical flip-flop made by LiNbO3 intersection waveguide
MING HAI, SHINSUDE UMEGAKI, and SHUN-ICHI TANAKA

An optical triggered flip-flop is demonstrated using two hybrid bistable optical devices consisting of series connection LiNbO3 intersection waveguide in intergrated optical circuit. The experimental result, is given.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 5 441 (1989)
High-gem LiNbO3 optical parametric oscillator
HUANG WBIPING, XIE SHENGWU, JIANG XIUMING, WANG PBIJUN, and CHEN YINGLI

We report in this paper a high-gain tuned LiNbO3 optical parametric oscillator pumped by a Q-switched ruby laser. The maximum output energy and conversion efficiency is as high as 50mJ/pulse aud 19 % respectively. The oscillator is continuously tunable from 1.1444μm to 1.7652μm.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 4 380 (1989)
Absolute calibration of VUV intensity using branch ratio
WEI LEHAN, Wu XIAOLAN, Fu JIKAI, and WANG SHUYA

The absolute sensitivity of VUV gracing incidence VUV monoohromator was calibrated on tokamak using branch ratio. The calibrated range is from 15A-1640A. The technical problems are discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 4 375 (1989)
Normal astigmatic character of astigmatic holographic element
YANG XUELING

Possibility of making an optical element of astigmatic character (astigmatic holographic element) by holographic method is analyzed theoretically. The astigmatic character in the space normal direction is researched in detail. The experimental results are given. The advantages are easy to operate and ecomomy.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 4 370 (1989)
Characteristics of IR stimulated emission from two-step excitation of Li-vapor at different frequencies
LI YONGFANG, LI XIANGSHENG, HU YIXIAN, and FU KEDE

In this paper, we report the five lines of IR stimulated emission and cascade radiation from two-step excitation of Li-vapor at different frequencies. The characteristics of the stimulated radiation are discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 3 285 (1989)
Electrostatic biprism with quadratic potential distribution
MA JIAN, FU SHUFEN, and WANG ZHIJIANG

A new electrostatic biprism-Quadratic Potential Distribution Biprigm is proposed, which as possible to increase the intensity of interference electron as well as the range of equidistanoe interference fringes.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 2 190 (1989)
Determination of normal harmonic current at silver surface under ultrahigh vacuum condition
ZHENG WANQUAN, LI LE, DONG SHUTAN, and ZHANG ZHIMING

We have measured the optical second-harmonic generation at free silver surface under ultrahigh vacuum condition. The value of the phenomenologioal parametre "a", introduced by Rudriok and Stern as a measure of the normal surface current, is determined to be - 4.0±0.8 at inoiden 1.064μm fundamental radiation.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 2 186 (1989)
Refracted near-field technique for the measurement of optical fiber refractive index profiles
YIN AIE, JIANG ZHONGXUAN, and ZHANG YILONG

The basic principle and experimental method of refracted near-field technique for the measurem nt of optical fiber refractive index profiles are described. The measured results for multimode and mono-mode fiber profiles are provided and compared with that by reflection technique and near-field technique. The spatial resolution better than 0.8μm, and refractive index sensitivity better than 2×10-4 are obtained in the experiment.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 2 181 (1989)
Improved approximate scalar finite-element analysis of optical waveguides
ZHAO ANPING, and YU RONGJIN

The match conditions of wave vector is firstly used for solving the strip waveguide problems by approximate scalar finite-element method in this paper. Thus the two-dimensional problems are simplified into two one-dimensional ones. This may provide a new approach for less computer memory and time, and retains all the advantages of approximate sealan finite-element method.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 2 175 (1989)
Self-mode-locking in phosphate glass laser
ZHANG GUOXUAN, HUANG GUOSONG, CHEN ZEXINQ, and LIN FUOHENG

The phenomenon of self-mode-looking in phosphate glass laser is reported. The experiment results have shown that the probability of self-mode-looking can reach 100% when the pumping power is high enough and the length of the resonator is longer. The experimental results have been analyzed and discussed in this paper.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 2 170 (1989)
The superiority of laser cavity folded along flow direction
WU ZHONGXIANG

The 3-dimensional radiation Seld distributions, saturated gain distributions, output powers and efficiencies in various cavities of gas dynamic laser are analysed by simulating calulation and comparison. The results predict the superiority of laser cacities folded along flow direction. The essential laws are applicable to other kinds of high speed flow gas lasers.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 11 1053 (1989)
Imaging two-dimensional objects composed of discrete points with a cross-grating interferometer
WU JIANHONG, CHEN LINSEN, and JIANG YAGUANG

In this paper the second cross-grating of a cross-grating interferometer is replaced with two one-dimensional gratings and the two fringe boxes of x and y directions are separated. When an object is composed of N discrete points, the image, N2 points, can be obtained from the two fringe boxes, consisting of the N correct ones and N(N - 1) false reconstructions. The second image is obtained by rotating the cross-grating interferometer an angle about its axis of symmetry. Comparing the first image to the second, we discover that the N(N-1) false reoonstruotiong are different and the N oorrect image points are the same. By multiplying the two images, the false reoons—tmotions are eliminated and the correot ones are obtained. The experimental results are given.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 11 1047 (1989)
The surface enhanced Raman scattering of piperidine adsorbed on silver electrode surface in nonaqueous media
GU RENAO, ZONG YAPING, and LENG YONGZHANG

This paper presents a study of surface enhanced Eaman scattering (SEES) spectra of piperidine adsorbed on a silver electrode surface in the methanol solution. The potential dependence of the SEES spectra and SEES spectra of piperidine during two kinds of the Oxidation-reduction cyclic pretreatment of the silver electrode are measured. We have studied the relationship of SEES of piperidine in the methanol and aqueous system. The experiments show that the enhancement factor of SEES of piperidine in methanol system is smaller than that in the aqueous system and their potential dependence is different.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 11 1041 (1989)
Optical absorption study of Ag+ implanted SiO2 glass
FEKG YIPING

High dose Ag+ implanted SiO2 glass and subsequently annealing were investigated by Rutherford baekscattering and optical absorption techniques, optical absorption spectra showed that the implanted Ag+ coalesce into colloidal particles, the plasma resonance maximum is at 400 nm. The Ag colloid of 18 A in radius was estimated from measurements of the half-width of the plasma resonance by using the Mie theory and Doyle method.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 11 1037 (1989)
Compound panoramic holography of orthoscopic and pseudoscopic image
Fu SHENGIQIAO

This paper presents a new optical holography for compounding reconstruction orthoscopic image and pseudoscopic image of the recorded object. Better stereoscopic and artistic effect can be obtained as the information on both the front side and the back side of object recorded in a hologram can be seen at the same time. In this paper, the recording principle and the experimental technique and results are introduced.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 10 955 (1989)
Thermo-optic switched directional coupler with reversed Δβ
CHEN ZHENG, and WU GANG

A conception of thermo-optic switched directional coupler with reversed Δβ is proposed and a testing device with two paires of electric heaters has been fabricated on glass substrate. At 1 kHz square wave voltage modulation, analyzing optical output power from the device by using a high speed 12-bit A/D converter connected with a computer, shows that both a bar-state and a cross-state have been obtained. Because glass waveguides are optical damage-free, polarization-insen sitive, and easy to fabricate, the device can be widely nsed in the oases that do not require high speeds.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 10 951 (1989)
Orthogonally polarizing 180° rotational shearing interferometer and its application
ZHU ZHIMINQ, XU KETAO, and ZHAHG ZHIMING

An orthogonally polarizing 180oooooooooooooo rotational shearing interferometer is reported and the experiment shows distinctive power and superpreoision in optical testing. Eccentricity and the coefficient of primary coma and distortion were quantitatively measured.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 10 944 (1989)
Wide-Temperature And Low-Loss Single-Mode Directional Coupler
LU SHAN DA, FENG MING HE, and HUANG YONG

This paper describes the fabrication of a wide-temperature and low-loss fused single-mode optioalfibre coupler. The device is fabricated from standard communication fibre. The specifications of the packaga device at 1.52μm are as follows: splitting at 0(?)50%,splitting ratio tolerance 40 dB. The splitting ratio is highly sensitive to operating wavelength, but insensitive to polarization of input light.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 1 93 (1989)
Investigation of a novel integrated optics microdisplacement sensor
CAI BORONG, CHEN ZHENG, and LI YUXIANG

This paper reports a novel integrated optics microdisplacement sensor which has been fabricated in our Labs, based on S. Honkanen s proposal. The NA approach is firstly used for ca]culating the characteristics of the sensor and all the performances of the device are measured. The theoretical analysis and experimental results are in agreement basically. Several ways to improve the sensitivity of the device are presented. The sensor could be used in a wide area, such as vibration, acceleration and acoustic sensing etc.

Acta Optica Sinica
Jan. 01, 1900, Vol. 9 Issue 1 88 (1989)
A new method for phase correction in FTS
FAN SHIFU, and XU XIAOCHU

A new methed for correction of asymmetrical interferogram is presented. After once application of this new method a asymmetrical interferogram will be absolutely symmetric so that the distortion of complete spectrum will bo corrected. The theory and experiments show that this new method is more efficient than other available phage correcting methods in FTS.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 9 861 (1988)
Photon statistics of degenerate two-photon laser
WANG ZHICHENG

Starting from the master equation for density operator of the atoms and the field mode and applying the operator method of adiabatic elimination of the atomio variables developed by Haake and Lewenstein, we derived the Fokker-Planck Equation for Wigner function of the lightfield and its steady-state solution. With a Gaussian approximation to the solution, analytical and numerical results on the photon statistics for various pumping strengths are obtained. Comparisons with previous works are made.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 9 856 (1988)
On catastrophe behavior of the three-level laser
SUN MAOZONG

The behavior of the three-level single-mode laser in the presence of an applied field and a saturable absorber is revealed near the losing -threshold. It is shown by quantitatively calculating that nonlinearity of laser field and introduction of applied field cause the correspondence of steady states of the laser with the canonical cusp catastrophe manifold. In this paper the physical meaning of the cusp catastrophe manifold is explained in more detail. The quantitative condition for optical bistability generation is given.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 9 851 (1988)
The effects of rotation and scale change with amplitude-compensated filter
Mu GUOGCANG, WANS ZHAOQI, and WANG XUMING

In this paper, rotation and scaling properties with an amplitude-compensated matched titer is presented. Computer simulations show that this kind of filter is much more sensitive as compared to a matched spatial filter or a phase-only one. Correlations against rotation angle and scaling factor for all the three filters are also presented.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 8 764 (1988)
A stigmatic grazing incidence grating spectrograph and laser plasma XUV emission spectra
ZHANG ZHENGQUAN, FAN PIUZEONG, ZHAO SHICHENG, ZHOU JINZHI, and JlN RENSHAN

In this paper the design and the performance of a stigmatio gazing incidence spe-ctrograph with a spherical grating and a toroidal mirror, built by our group, are given and the application to the observation of the spectra of beryllium, carbon. Lithium fluoride and calcium fluoride in the range 20-120A is reported.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 8 762 (1988)
Fluorescence spectrophotometric assay of O6methyIguanine in low concentration
ZHUANG DAKUI, LIU YASHU, QU YONGHUA, and WU YIQIAN

The determination of chemical oarcinogen-DNA adducts is necessary for research of molecular epidemiology and mechanism of chemical carcinogenesis. A method ig presented in this paper for the detection of putative addnots by using fluorescence spectroscopy. The main advantages include high sensitivity and high selectivity. The minimum detectable amount of O6-MEG is 0.01 fmol/ml. The sensitivity of detection is an order of magnitude higher than that of radioimmunoassay.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 8 759 (1988)
Periodic deca7 and revival effect of the atom interacted with two-photon field
PENG JINSHeng, and HUANG XIAYAO

The exact solution of time behaviour of the two-level atom interacted with two-photon field is obtained. The periodic decay and revival effect of the atom is also revealed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 8 756 (1988)
Holographic coupler for fiber-optic Sagnac interferometer
ZOU YUNLU, and HSC DAHSIUNG

The crucial parts of a fiber-optic sensor (FOS) are 3dB couplers. It is a novel idea that a holographic lens is made as the coupler for a fiber-optic gyro. Theoretically we explored the possibility of this way and achieved it experimentally. According to Kogelnik s Coupled Wave Theory, under the Bragg condition, the diffraction efficiency of transmission holographic gratings, whose recording material is fit for certain conditions, theoretically, is up to 100%.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 8 751 (1988)
A study on luminescence of tautomeric laser dye Kiton red
We ZHISTGLIIAXg, XIE YANYAn, and LIN LIHUASG

This paper reported that PS laser teohniqug was used to measure the fluorescence lifetime of kiton red dye. Experimental results show that fluorescence decay of Kr molecules behaved as double exponential form, which verified the existence of tauto-meric equilibrium between enol form and Kito form in the Kiton dye solution.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 8 747 (1988)
Rapid laser etching of fused SiO2
PAN DAREN

Rapid laser etching of fused Si02 has been achieved using a 10.6μm CW CO2 laser and several etchant gases. Etch rates of above 200μm/s and clean, smooth surfaces have been obtained. The observed experimental results are explained in terms of the presented mechanizins.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 8 742 (1988)
Spatial fringe-scanning method for analyzing interference fringes
CHEN JINBANG, and LI XING

Interference fringes with a tilted wavefront are spatially scanned perpendicularly to the carrier fringes and analyzed using FFT algorithm. It is not necessary to use any device in order to modulate interference fringes temporally. Itis also not necessary to locate fring centers and to assign interger order number. In this paper. we propose these techniques for determining the topography of a wavefront from an interferogram. The accuracy is higher then standard deviation of 1/50 wavelength.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 7 669 (1988)
Fresnel rhomb used as a optical wavelength plate
DING DAJUN, and LIU HANG

We have constructed Fresnel rhombs used as a λ/4 or λ/2 wavelength plate. This design was based on Fresnel s principle in a total internal reflection. We have made a transformation from a linear to a circular polarization or a rotation of a linear polarization vector in ultraviolet spectral legion.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 7 667 (1988)
Approximate Talbot self-imaging effect for Gaussian beams and two new applications of Tablot effect
LU HONGJUN, and BAI GUIRU

The present paper has discussed some characters of appraximate Talbot self-imaging phenomena for incident spherical Gaussian beams. Upon using Talboi self-imaging a convenient way for measuring divergence angle of Gaussian beams and ultra-high amplification of the self-imaging in some condition are also proposed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 7 663 (1988)
ABCD law for nonsymmetric optical systems
LIN QIANG, LU XUANHUI, and WANG SHAOMIN

Diffraction integral formula for general nonsymmetric optical systems is clearly derived by means of vector analysis. Based on the concept of tonsor complex curvature of radious, the ABCD law for nonsymmetric optical systems is presented. Also, an applying example is illustrated.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 7 658 (1988)
Doppler-free saturated absorption spectroscopy of CO2 and SF6 molecules by using a resonant optoacous tic multipass cell (MPC)
CAI BANGWEI, LU BAIDA, and CHEN XIMING

The Doppler-free saturated spectroscopy of the CO2 and SF6 molecules is investigated experimentally by using optoacoustic detection with a resonant multipass cell. The width of the absorption dip for CO2 is measured to be about 2.5 MHz, five absorption dips for SF6 are observed in the experiments, and the dip width is about 1.9MHz. In both oases the spectral resolving power is greater than 107.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 7 653 (1988)
Statistical properties of light field at degenerate parametric down-conversion
SUN WANJUN

The evolution operator of state for degenerate parametric down-conversion has been obtained. By means of state function we have studied the statistical properties of light field at degenerate parametric down-conversion.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 7 648 (1988)
Preparation of multilayer soft X-ray mirrors
ZHENG TIANSHUI, and SHEN YUANHUA

In thia paper we described the design and preparation method of Ni-0 multilayer soft X-ray mirrors with emphasis on the thickness monitoring method. The optical coefficients of Ni and C superficial layers at 6328 A are determined by ATR method and so their thicknesses could be monitored by measuring the transmittanoe of the sample at that wavelength during deposition. The depth profile of a sample was analyzed with AES; the diffraction performance at 1.54A and the reflectivities at soft X-ray region of some samples were measured and compared with the theoretical calculations.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 6 572 (1988)
Experimental study on optical second harmonic generation of Langmuir-Blodgett monolayer assembly
CHEN GANG, WANG GONGMING, ZHENG JIABIAO, ZHANG ZHIMING, TAO FENGGANG, and XU LINXIAO

The second order non-linear polarizability of Langmuir-Blodgett multilayer formed with one sort of molecules is zero because of the counteraction of non-linear polarization in adjacent monolayers which have opposite orientation. The magnitude and sign of effective non-linear optical coefficient of Langmulr-Blodgett monolayer with different polar groups have been studied experimentally by optical second harmonic gener ation technique. We alternatively assembled the monolayers which have opposite sign of polarizability and successfully have their non-linear polarizability superposed construtively. In this way, we can obtain a molecular membrauce poseessiag much larger effective second order non-linear optical coefficient.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 6 567 (1988)
Continuous tunable frequency-stabilized 1. 52μm He-Ne transverse Zeeman laser
ZHAO JIAQI, AN JIALUAN, CAO JIANFING, LIU HANTIAN, and LI YINZHU

A1.52μm single-mode He-Ne laser with internal mirror in transverse magnetic field have been successfully developed. A method is suggested that laser frequency on looking condition can be continuously tuned along optimal S type curve. By this method laser frequencies have been obtained with a relative frequency stability in the order of 10-11, sample time of 0.1-1S and over a wide range (100 MHz). It can be used as a optical source in the single-mode fibrle communication.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 6 563 (1988)
Colored Morie topography
LIU LIREN

Based on the dispersion of prism, a new method is proposed for pseudocolor-coding the fringes of Moire topography. Two typical systems with a single prism and a pair of complementary prisms are discussed. The experimental of demostoation is given too.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 5 478 (1988)
The effect of parametric amplification produced picosecond pulses
CUI YIBEN, QI HONGXING, LI GONGPU, and PAN ZHONGHAN

In this paper the parametric LiNbO3 crystal of angular tuning pumped by 0.53μm trains of picosecond ultrashort pulses was reported. We have obtained energy converse efficiency 1% of single-pass parameirio amplification. The frequency range 0.8-1.6μm of timing curves of the signal and idler pulses was mersured.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 5 474 (1988)
Coupling between two doubly cladding single mode fibers
CHEN ZHIHAO, and YAO HUIHAI

An accurate analytic expression of coupling coefficient between two parallel doubly cladding single mode fibers is given in this paper.The coupling coefficients as a function of normalized frequency parameter V are calculated for fibers with raised, matched, and depressed inner cladding indices. The coupling coefficients as a function of normalized distance D/a are also given with different V. The formula can be used to compute both the coupling coefficients for both x-polarized modes and the coupling of y-polarized modes further. It can also be used to analyze ilie coupling beliweeri two fibers with their large refractive-index difference, as well as polarisation obaraoterlstioe of optical fiber couplers.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 4 379 (1988)
Optical PAM-to-PDM convertion:An application of optical critical slowing down effect
ZHONG LICHEN, and GUO YILI

In this paper, a new function that convers optical pulse amplitude modulation (PAM) to light pulse duration modulation (PDM) for a bistable optical system is proposed and observed experimentally. This PAM-to-PDM convertion is based on the optical critical slowing-down effect.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 4 374 (1988)
Phase noise of semiconductor laser due to external optical feedback
YE JIAXIONG

Phase noise in semiconductor laser due to external optical feedback is investigated theoretically. The theoretical analysis introduces a feedback coupling rate K and linearized rate equations. We also derive the experssion of phase noise power spectrum density of semiconductor laser. It is shown that the phase noise spectrum density shift periodicity with the length of external cavity and the peak value of power spectrum density varies considerably with the feedback coupling rate.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 4 368 (1988)
Application of Kramers-Kronig relations for calculating phase dispersion of reflective mirrors
LIANG PEIHUI, ZHANG SHAOFENG, and WO MINZHENG

The phase dispersion of optical elements plays an important role in the generation and transmission of ultrashort pulses. In this paper we put forward a method for directly calculating the phase dispersion of reflective mirrors from reflective spectra by using Kramers-Kronig relations. Taking multi-layer dielectric coating and Al coating as examples, the method is analysed and discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 4 363 (1988)
Scanning tunneling microscopic images of the surface of graphite
YAO JUN KN, SHANG GUANGYI, JIAO YUEKAN, YI YUAN, BAI CHUNLI, HE JIE, ZHONG JICHANG, and RONG DEYIAN

In this paper, a scanning tunneling microscope constructed in this laboratory using a single tube scanner was described. Line scan (amplitude modulation), top view (brightness modulation) and shaded topographical images of the surface of highly oricented, pyrolytic graphitc (HOPG) were shown.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 3 287 (1988)
Digital phase contrast imaging
ZHOU ZHIQING

The digital phase contrast method is described, and it is used to process the data acquired from Scanning Laser Acoustical Microscope. Images obtained are quite clear.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 3 284 (1988)
Investigation on the rotating a perture methods of white-light speckle photography
CHEN BINGQUAN, and CHENG CHUANFU

Rotating aperture methods of white-light speckle photography used for measuring the dynamic problems is proposed in this paper. In addition to the advantages of rotating aperture mothods of laser speckle photography, in particular it can be used for dynamic measurement in the field.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 3 281 (1988)
The magnetooptic effect of single-mode fibers
CHEN XIKUN, and ZONG WKIYONG

In investigating the polarization property and magnetooptic effect of single-mode fiber, we need to consider not only its Faraday effect but also its birefringence. In this paper, the theory of the magnetooptic effect of the single-mode fiber is described with the Jones matrix. The Jones matrix expressing the birefring ence and magnetooptic effect of the single-mode fiber is derived. And the relation between the output light intensity and Faraday rotation angle of current sensor system is presented using Mueller matrix.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 3 276 (1988)
Measurement of polarization characteristics of Bow-Tie fiber
CHEN YIQIANG, and HUANG ZHAOMING

The paper describes a simple experimental process, including the optical system and calculation method for measuring the beat length and extinction ratio of bow-tie fiber.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 3 271 (1988)
Optical wave propagation through inhomogeneous random medium——The solution of the m-n th moment equation of multiple scattering
WANG ZHENGSONG

The analytic solution of the multiple scattering m - nth moment equation with different wave numbers and different posiiions is given in the small angle scattering approximation for optical wave propagated through such a random medium, that the material parameter fluctuates inhomogeneoursly in the dirction of propagation and homogeneously in the direction transverse to the propagation path. The applications of the solution to the problems related with the optical beam propagation are discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 3 266 (1988)
Point-wise analysis of rotating aperture method for speckle photography
GU JIE, and SHEN YONGZHAO

In this paper, we make a point-wise analysis of a specklegram made by rotating aperture method for speckle photography. The Young s pattern is generally not equal spaced straight fringes, but curved fringes according to the dynamic process of displacements. In this paper, the meaning of the pattern is explained, theoretical analysis and experimental demonstration are presented.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 2 188 (1988)
A simple method of reconstructing refractive index field with a wide field angle
GAO YIQinG, KAng QI, and DING HANQUAN

In this paper, a dual-illumination-beam and dual-reference-beam holographic system is designed with which interferograms of flame temperature field over a 90° angle of view are obtained instantaneously. A simple reconstruction metod is discussed. The effects of projection number and the measurement error on the reconstruction precision are determined by computer simulation. The temperature distribution in a plane are reconstructed from the experimental data. The results are compaed with thermocouple measurement.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 2 181 (1988)
Optical design problems of wide conversion lens
WANG SHUZE, and LI YUANKANG

In this paper, a reverse Galilean telescope is used as a wide conversion lens and design of the 1.67× lens system is given as a Living example. Being manufactured and practised, the 1.67× wide conversion lens confirms its good quality and utility.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 2 177 (1988)
Transfer function improvement by means of synthesis of different defocused electron micrographs with unsymmetrical rotational aberrations
SHEN XIAOQING, LI MINGJIN, ZHENG SHIHAI, and LI FANGHUA

The different defocused electron micrographs with the unsymmetrical rotational aberrations are synthesized. It makes possible to get a relatively broad distribation of phase contrast transfer function(PCTF). The PCTF in the spatial frequency area has the similar phase and the regions near the zero point of transfer function, which do not transfer information, are filled by other transfer function. The resolution of electron micrograph is improved.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 2 171 (1988)
Nonlinear guided wave in symmetric slab leaky waveguide
XUE BINGZHANG, WANG QI, and CAI YINGSHI

Based on plane wave theory, the propagation characteristics of TEo modes have been studied in a symmetric slab leaky waveguide of a nonlinear djelectric film. Our results show that steady TEo modes can not exist if the film thickness is above a critical value, two TEo modes with different peak field intensities may exist at most if the film thickness is below the critical value. With the decreasing of the film thickness, the peak field intensity difference between the two modes becomes large.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 2 166 (1988)
A new proposal for phase—only CGH and its application
HUANG XIANGYANG, CHEN WEIFENG, YING XUANTONG, and JIA YURUN

A new coding method for a CGH with pure phase is proposed and demonstrated in which only two cells are needed for each sampling point.The phase-only CGH produced by the proposed method can record any complex wavefront with advantages of on-axis reconstruction, high SBW and high diffraction efficiency.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 2 162 (1988)
The principle of ring laser magnetic sensor for weak field and it experimental investigation
Zou DATING, ZHANG SHULAN, FEN TIBUN, and TIAN QIAK

This paper reports the principle and the experimenlal vesults of the ring laser magnetic sensor for weak field (RLMS) for the first time. Theoretical analysis indicates that the ELMS suseceptibility mainly depends on the merit coeffecient of magneto-optical material. In our experiments a terbium-silicate glass of 20 mm length is used as a Faraday cell, a susceptibility of 2.9 ×10~(-8) Oe/Hz (0.0023A/m·Hz) and a random shift of less than 2.3Hz during 9 hour have been obtained.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 12 1133 (1988)
A new scheme for improving stability of intensity modulation optical fiber sensors
ZHU ZIMIN

In this paper, an improved Beheim mathod is described, by which the stability of the intensity modulation optical fiber sensor can be enhanced in the measurement of many physical quantities, the experimental results for measurement of relative disp acement are given.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 12 1129 (1988)
A study of threshold LLL-CCD cameras
WEI ZEBIN, and ZOU YISONG

A concept of TV-signal to noise ratio transfer function (SNTF) is proposed in paper, and a deterotive equation is established based on the SNTF. Theoretical calculated resulte well coordinate with the experimental results. Values of detectivity of LLL-CCD cameras under several different conditions are calculated based on the equation with the aid of computer. After analysis of the results, some ways of improving detective ability of LLL-CCD are proposed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 12 1123 (1988)
Influence of pump field on squeezed state generated by degenerative parametric amplifier in absorptive media
LI YUFANG, TAN WEIHAN, and ZHANG WEIPING

Making use of the result given in the previous paper, this paper inyestigatefl the influence of intensity and detuning of the pump field on squeezing and gives the numerical calculated result.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 12 1119 (1988)
A holographic method for in situ observing effective coherent length and TC periodicity of the multi-mode laser
YlN JIANPING, and BAO REN

According to the J. Upatinick s principle of elliptical equi-optioal path, we suggests a holographic method for in situ observing the effecting coherent length and TC periodicity of the multi-lengitudinal mode laser. It s basic principle is described and relative experimental results are given in this paper.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 11 1053 (1988)
Influence of stimulated Raman process on fundamental solitons in fibers
QU LINJIB, and XIE SHUSHING

With the aid of computer simulation, we study energy spectrum erolntion of the fundamental solitons propagating in fibers, caused by Raman self-pumping. We find that the self-frequency shift effect will be accompanied with bandwidth change and energy spectrum distortion of the solitons whose durations are shorter than sub-picosecond.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 11 1048 (1988)
Resonance enhancement of photoacoustic FTIR spectroscopy of solid samples
YU GANG, ZHANG CHUNZHOU, and ZHANG GUANGYIN

The resonance enhancement of photoaconstic signals due to the frequency response of the photoacouatic sample cell in FTIR-PAS measurements was observed for the first time. The frequency response analysis of the cell shows that this effect originates from the unflat response of the pressure transducer of gas in the chamber. The possibility of improving the sensitivity and the S/N ratio of the photoacoustic measurements with the resonance enhancement method was discussed in this paper, and an example of using this method to analyze structure defects of SPs in the conducting polymer PTh samples was also given.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 1 93 (1988)
Fabrication of blazed grating by sloping V-groove structures on silicon
HUANG XINFAN, LI LIANGZHU, GAO WENQI, and YE QUANSHU

oriented silicon is used as substrate and the surface is at an angle of 25.24° with planes. A 36 μm period diffraction grating as a mark during the anisotropic etching of silicon was generated on Si by thermal oxidation and photo-etching technology. Subsequently silicon wafers are etched in the coventional anisotropio etching solution. Continuously slanted V-groove structures on silicon have been fabricated which is used for a 36 μm groove distance blazed grating can be obtained by further reducing the groove distance.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 1 89 (1988)
Complex Huygens wavelet expansion and its parameter selection
RUAN YINGZHENG

A new method for analysis and evaluation of wave fields, complex Huygens wavelet expansion, is presented, which replaces the coventional Huygens wavelet bya secondary source with complex coordinates, evaluates the field from each wavelet by complex ray theory, and superposes the individual contributions to construct the wavefield from the primary source. The method of this expansion is illustrated. In comparison with exact reference solution, the error of the method is less than 1%, provided that the expansion parameters are properly chosen.

Acta Optica Sinica
Jan. 01, 1900, Vol. 8 Issue 1 83 (1988)
Investigation on dignoses of earlier period cancer diseases using laser spectra
HUI LINGKAI ET AL

We have compared the different compositions of the blood for cancer patient with the composition of the same kind of the healthy person. To discover the spectra of them present obvious difference and the spectra for the blood of the different kind of the patient also present obvious differece, but the spectra of the specifieness compositions for earlier peiod cancer disease is same which close to spectrum of the That the method is used in the earlier period diagnoses is maybe the most good and can bo used in checking widely. It is not only simple but also quick.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 9 864 (1987)
Polaried aperture method for speckle photography
GU JIE, and SHEN YONYZHAO

In this paper, we have discussed the function of a polarizer in multiaporture method of speckle photography and proposed a new aperture-polaried four-aperture for speckle photography.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 8 767 (1987)
Precision measurment of thermo-optic coefficients of optical materials——A thermo-optic coefficient measuring instrument
LIU HAIQING, JIN DEYUN, and HUANG GOUSONG

This paper decribles a kind of thermo-optic coefficients measuring instrument which can be used for exact measurement of five coefficients of optical materials. A new design shich combining two kinds of interferometers, computer control and data processing and adoped, resulting in a high-precision measurement. An accuracy of ± 3 × 10-7℃-1 has been achieved in measuring the thermal expansion coefficient α in a low temperature region, temperature coefficient of refractive Index β and thermo-optic coefficient of refractive Index β and tiiermo-optic coefficient ω.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 8 760 (1987)
A theoretic explanation of the absorption spectra of YIG and YGG: Fe3+ at crystal field of low symmetry
BAI GUIRU, and XU CHANGQING

Using SOF d-orbital theory of Fe3+-ion in complex, we have calculated the absorption spectra of YIG and YGG:Fe3+ at low symmetry D3d and S4 respectively. With only two parameter N and μ, we have explained the splitting at 10800 cm-1, 21160 cm-1, 25700cm-1, 27600cm-1 in YIG, and pointed out that the peaks at 26320cm-1 and 26970cm-1 in YGG:Fe3+belong to two center transitions of Fe3+-ion pairs. Some confusion in the theory of the absorption specta of YIG and YGG:Fe3+ have been clarified.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 8 753 (1987)
A new method for realizing image edge enhancement in a white-light processor
Zhang Yonglin

A new method for realizing image edge enhancement in a white-light processor is presented. Compared with conventional method, its primary advantages include elimination of coherent noise and obtaining accurate edges in a simple process of two dimensional edge hightening of images.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 8 748 (1987)
Measurement of optical constants of LiNbO3 in the range of abnormal dispersion
SU DAZHAO, XU JINMIN, ZHANG WANLIN, and ZHANG GUANGYIN

The reflection spectrum of LiNbO3 in the range of 80cm-1-2800 cm-1 is measured by means of a 170SX Fourier transformation infrared spectrometer. The optical constant spectra of LiNbO3 in the same range are calculated rapidly and accurately using the integral form of the Kramers-Kronig relation. The transversal frequencies wT, longitudinal frequencies wL and high-frequency dielectric constants ε∞ of A1 and E modes can be obtained directly from the spectra. The oscillator strength is calculated and the mutual coupling between these oscillators are discussed. The 670om-1 mode Is recognized as a fundamental frequency of the E mode.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 7 667 (1987)
A new kind of heterodyne fiber-optic gyroscope
PENG GANGDING, HUANG SHANGYUAN, and LIN ZONGQI

In this paper, a novel fiber-optic heterodyne detection technique of rotation rate is described. Using electro-optic frequency shifter and highly birefringent single-mode fiber, the heterodyne fiber-optic gyroscope system no more needs the use of acousto-optic devices and is free from the direct-current drift in the electronics. In addition, the reciprocity of the optical path in the system is improved. Preliminary experiments have shown a good linearity of the scale factor.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 7 662 (1987)
Birefringence and polarization characteristics of soliton in a single-mode optical fiber under elastic deformation
ZHOU GUOSHENG, and LI XUENONG

The influences of elastic deformation on the soliton propagation characteristics in. a single-mode optical fiber are studied by treating the deformation as perturbations. It is indicated that the deformation also can cause polarization. dispersions and birefringences in soliton propagations, same as in conventional propagation.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 7 656 (1987)
Investigation of degeneration mechanism and improvement method of infrared (Ge/SiO) stack filters
LI ZHONGQI, LIN CHENZAN, and Li ZHeRGEN

The degeneration mechanism of characteristics of infrared (Ge/SiO) stack filters is discussed based on experimental results. We propose a method to prevent such degeneration of characteristics. By using the method, high-quality filters have been obtained which can withstand immersion tests in water and solutions of salt or acid.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 7 651 (1987)
Multiphonon-assisted radiative transition of Cr3+ in glass
LIU HUIMIN, and GAN FUXI

By using laser narrow line excitation at different wavelengths the linear relationship between excitation energy and fluorescent Stokes shift of Cr3+ in glass could be found. Therefore, the crystalline dynamic field parameters of Or3+ are deduced.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 6 575 (1987)
Rectification of principle errors in shadow Moire topography
YUAN YULIN, and ZHANG YANGYUN

It is proposed that there exists principle errors in the shadow Moire topography. The mathematical expression is derived in order to correct such errores. Moire contour photographs are presented. Corrective reckoning of photographs indicates that these formulas are valid.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 6 567 (1987)
Luminescence of Cr3+ ions in Na2MgAlF7
WU GUANGZHAO, ZHANG XIURANG, ZHANG SHUNXING, SHI ZHENHUA, and A. LUPEI

The luminescence properties of Cr3+ ions in powdered Na2MgAlF7 multicrystal were studied experimentally. The fluorescent emission from 4T2 covers a wide region of 700 nm-1050 nm in the near-infrared. At 77 K, the fluorescence lifetime is about 310μs and the decay curve deviates slightly from single expenential form Temperature quenching occurs at above 200K. Several structures on the spectra are discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 6 563 (1987)
Mollenstedt biprism and partial coherent electron beam interference
FU SHUFEN

An expression for electron deflection angle caused by Mollenstedt biprism was deduced according to the similarity between electron optics and geometrical optics. A comparison between optical Fresnel and Mollenstedt biprism was given. The effects of partial coherence of electron beam on interference field were pointed out. The obtainable maximum number of interference fringes were discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 6 558 (1987)
The discussion of phase error in diffraction equation
CHEN GON, and WU ZHUOCAI

Brsed on the wave theory of optics, the affect caused by the phase error in Fresnel near-field diffraction equation is analysed. Taking single slit as an example, the relationship between phase error and resulting accuracy is given. Prom calculating of the focal plane intensity distribution on Linear Presnel Zone Plate, the results of using Fresnel diffraction equation is stated when the phase error requirement is not satisfied. Some facts affecting the focal plane intensity distribution of LFZP are given.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 5 477 (1987)
Discussion of measuring signal-noise ratio of high power laser pulse using silicon photoelectronic switch
ZHI TINGTING, and CHEN LANYONG

The laser damage of silicon in silicon photoeleotronic has been investigated with a 1.06μm laser. Laser pulse duration is 50ps and energy is 20mJ/pulse. Calculations show that the damage occurs at the silicon surface and depend on pulse duration time, laser energy flux and manner of the laser irradiation. The experimental result is in agreement with the theoretical analysis.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 5 473 (1987)
Electro-optic induced optical waveguide and modulator in SBN:60
ZHANG DIYANG

The first observation of eleotro-optio induced waveguide and dark spot phenomena in SBN:60 is reported in this paper and a new eleotrooptio modulator with lower driven voltage, high modulation factor of amplitude modulation is demostrated.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 5 468 (1987)
Study of Goos-Hanchen shift of reflected beam from absorbing medium
LENG GUANGYAO

General expressions of Goos-Hanchen shift for both s and p polarizations from absorbing medium has been derived in this paper. Let the extinction coefficient be equal to zero, they will be simplified to the formulae[1] given by M. McGuirk and C. K. Carniglia, which are only fit for non-absorbing medium. The shift from absorbing medium occurs at any incident angle except zero angle. On Gallium surface, Goos-Hanchen shift may have several wavelengths.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 5 464 (1987)
Application of the Monte-Carlo method to light scattering from randomly distributed particles in thin layer
WANG YIPING, and WN ZHENSEN

We use the Monte-Carlo method to calculate the intensities of transmission and reflection of a collimated light beam scattered from randomly distributed particles in thin layer. The results obtained are compared with those calculated by the transport theory of diffusion approximation. When the scattering is nearly isotropic, both of the results agree well. When scattering becomes anisotropio, the results from Monte-Carlo method are reasonable, while the theory of isotropio scattering approximation becomes invalid.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 5 458 (1987)
Experimental measurements of anharmonicity constants of CF3D
KUANG LIPING, XIE HUI, SONG QUAN, and KUANG YIZHONG

Experimental measurements of the infrared spectra of CF3D are reported. Five anharmonicity constants of OF3D are obtained directly from the equations which include fundamental frequencies, overtone and combination bands.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 4 382 (1987)
Hybrid optical-digital diagnosis of pneumoconiosis
CHEN YIWEI, LIU QIZHEN, HE YONGBAO, WU ZHONGYA, and YU ZHAOLIN

This paper presents the results of a joint study of automatic diagnosis of chest radiographs of pneumoconiosis. The Hybrid Optical/Digital Image Processing System of Fudan University (OPSA-1) was used. New algorithms developed for feature selection and classification led to a higher efficiency through experiments, with 94% accuracy in discriminating normal/abnormal radiographs.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 4 376 (1987)
Simultaneous measurement of the SELFOC lens optical index on axis no and quadratic gradient constant g by the equal object-image size imaging method
CHENG XIWANG

A new measuring method of the SELFOO lens optical index on sxis n0 and quadratic gradient constant g by the equal object-image size imaging method (EOSIM) is proposed in this paper. The resulte obtained has shown that this method is significant in practical application, and it can also simplify the surveying instruments.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 3 285 (1987)
Reman seattering of Ti diffuced LiNbO3 waveguide
SHI BANGREN

Four kinds of right angle Eaman scattering spectra of Ti-deffused LiNbO3 optical waveguide are reported in this paper. In the experiments on this waveguide, obvious anomalous phenomena in Eaman scattering spectra have been observed for four scattering geometries. The phenomena can be considered as the results of TE/TM mode conversion of incident beam in the waveguide.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 3 280 (1987)
Normalized cut-off frequencies of the LP11 mode in α-power fibers with a central dip
JIANG SHIJUN

A normalized mathematical model is used for describing the refractive-index profile of α-power fibers with a central dip. The cut-off characteristic of the second-order mode (LPu) is investigated by means of the power-series expansion method. Detailed normalized cut-off frequencies, which directly correspond to the actual refractive-index profile, are given. It is of advantage for theoretical design and measurement analysis of α-power single mode fibers.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 3 275 (1987)
On the polymerization of LB mono-molecular layers studied by ATR technique
YANG XINLIANG, CHEN GUANHUN, ZHANG ZHIMING, TAO FENGGANG, and XU LINXIAO

The polymerization of a Langmuir-Blodgett mono-molecular layers composed with 11-methaoryloylaminoundecanoio acid molecules is studied. It is the first time to show that these organic molecules will be straightened during the polymerization process.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 2 190 (1987)
A new approach enhancing squeezing
[in Chinese], and [in Chinese]

The re-squeezing approach was found to enhance squeezing. In this letter a hybrid transient second harmonic generation prooesses is discussed and large squeezing of mode w is obtained.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 2 188 (1987)
Review on the tolerance for colour contribution index of camera lenses (ISO/CCI)
SHEN HAILONG

In this paper, chromaticity co-ordinates of photographic effect of camera lenses corresponding to the six points, which limited the tolerance of ISO/001, is calculated by means of the basic formulae of colorimetry. The color difference of photographic, effects between the lenses according with the six points and the ISO standard camera lens is computed by using the OIE 1964 color difference formulae. According to these results, the rationality of the tolerance of ISO/CCI is discussed and the proposal for dividing the teleranoe of ISO/CCII into two regions is presented.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 2 181 (1987)
Optical logic processor by real time coding
YANG XIANGYANG, JIN GUOFAN, WANG SINUA, and WU MINXIAN

A real time optical logic processor is presented, that can perform binary logic operations in parallel. Experimental result is given of the system as a half adder.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 12 1136 (1987)
Approximate property of the imaging matric formula for selfoc lens
CHENG XIWANG

Based on the ray equation, imaging matric formula of the selfoc lens is derived is detail in this paper. Approximate property and applicable range of this formula can be seen from the derivation process, and the view of considering the formula applicable to the imaging of non-Gaussian optics should be corrected.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 12 1133 (1987)
On the econoimc tolerance of optical system
JIANG HUILIN

This paper tries to analyze the economic beneiits of an optical system, and to make a proposal in the estimating and calculating formulae for making optical tolerance with probability-statistical method. In the equations which are usec to find the solution of tolerance, the target function is minimum cost, while the restraint conditions are the permitted variation of MTF value and manufacturing ability. Its feasibility is proved by a practical example.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 12 1127 (1987)
Spatial differentiation by two sinusoidal gratings
CHEN YAN

On the bases of experimental and theoretical analysis, the author points out the feasibility of realizing optical differentiation by using simple sinusoidal gratings.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 12 1122 (1987)
Optical properties of Ce3+ in yttrium gallium garnet phosphor
LIU XINGREN, WANG XIAUJUN, and MA LONG

The diffuse reflection, excitation and fluorescence spectra of Ce3+ ions in Y3Ga5O12 garnet phosphor have been studied and discussed at room temperature for the first time. It has been found that the YGG:Ce3+ shows the optical properties of the allowed 5d-4f transition of Ce3+ ions whether under UV radiation or visible blue light or oathoderay excitation. The broad emission band extending from 430 to near 670 nm results from the transition of the lowest 5d level to 2FJ (J=5/2, 7/2) terminal state. In YGG, the optical behaviour of Ce3+ Is very similar to that of Ce3+ In YAG, but the positions of absorption and emission bands of Ce3+ shift toward shorter wavelengths.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 12 1118 (1987)
Error analysis for a ring-laser weak magnetic field sensor
ZHANG SHULIAN, ZHOU DATING, and FENG TIESUN

The main errors of a ring-laser weak magnetic field sensor are analysed and the methods to eliminate these errors are discussed. The error introduced by temperature coeffient of verdet constant of magneto-optical materials is derived theoretically. This is the main source of error due to temperature coefficient of a ring-laser weak magnetic field sensor after low expansion cavity materials and frequency stabitization technique have been used. The error introduced by Zeeman effect is given. The Zeeman effect error results from ihe magnetio field sensitivity of the gain, medium, and it is mixed with the magnetio field sensitivity of the Faraday magnetio-optical material. Bj locating a gain tube in each longer arm of the rectangular cavity, the Zeeman effect can be avoided. The two gain tubes haye the same parameters (such as core length, diameter, total and partial presure, discharge current and diamension of catitod). The infiuenoe of Langmuir gas flow effect can be eidmination by beating positive and negative rotations and then adding the beats of right and ligt rotations.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 12 1112 (1987)
Light propagation in active fibers
WENG TINGDUN, and ZHON GUOSHENG

In this paper, we deduce the equations of motion for both cw and long-pulse light in active fibers. We then solve the equations under zero-order and first-order perturbations by using the quantum theory about the polarization of an active material. We give a quantitative description of the evolutions of amplitudes and phases of the cw and long-pulse light, and discuss the influence of the active material on the group velocity of the long pulse light.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 12 1106 (1987)
A method of inspection of an optical synthetic aperture radar processor
JIN YOU

In this paper we take a general OSARP inspection as an example to explain the method of inspection of an OSARP. We relate the adjustable quantities of each adjustable assembly of the OSARP (Optical Systhetic Aperture Radar Processor) with each characteristic number of a SAR (Synthetic Aperture Radar) data film. The applicable range of the OSARP is obtained by testing the adjustable quantities. The imaging quality of the OSARP is inspected with the general testing targets and a shift lens. The advanced inspection of the OSABP is done wilii the simulated SAR daia films. It is a different way, but "the results are tiie same as tiie former, Finally, the ture SAR data film is processed to whow the oomprehensive imaging quality of the SAR and the OSAEP. Tite expearimentel pictures.and data presented in this paper are for reference only. The experimental results show that the method is applicable.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 12 1099 (1987)
Photon correlation spectra of unneutralized electrolyte solutions
LI MING, and WU CUNKAI

In this paper we discuss the dynamic property of light scattering of unneutralized electrolyte solutions and the photon correlation spectra.The resultsshow that weak un-neutralization can largely increase the measured diffusion coefficient and, comparing with neutral electrolyte solution, the diffusion coefficient of unneutralized one is more sinsitive to the scattering angle. For a dilute electrolyte solution of 10-3 molar with unnentralization of 1%, an enhancement of 102-103 in the diffusion coefficient can be obtained. The physical mechanism of unneutralization effect is discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 11 1051 (1987)
Optimum meridional image plane of off-axis paraboloidal mirror
XU SHI, and CHEN JUNREN

Analysis is made for the meridional imaging rays of a not-far-off-axis paraboloidal mirror, which indicates that there is an inclined optimum image plane of the off-axis mirror if certain approximation is satisfied and the aperture stop is properly located. The inclination and the blurred point image size on the image plane are derived. The analysis and the ray tracing result both show that the image quality is much improved on the inclined image plane.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 11 1045 (1987)
Research on photodissociation process for laser dye rhodamine 6G by ESR
FU WINBIAO, and WU ZHENGLIANG

Resear ch has been carried out on photodissociation process for laser dye rhodamine 6G by ESR. Experimental results show that there is the energy transfer between triplet of the dye and the free radicals in the solvent.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 11 1041 (1987)
A high repetition rate XeCl excimer laser
NAN YINGZI, WU HAIliN, WANG CHANSHAN, GENG XIULAN, and Li YINKAI

Configuration and performances of a high repetition rate XeCl exoimer laser are reported. A ceramio-metal grounded grid thyratron used as pulse switch, a transverse flow system, and a structure of fast transverse discharge of UV preionization are adopted in the laser system. The maximun output pulse energy is 200 mJ, maximum average power is 18 W at a repetition rate of 107 Hz.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 10 957 (1987)
Observation of leaky modes of a multi-layer quasi-waveguide
DING TIENAN, BEN BIGKFU, and ZHAO SHENG

A new method for measuring multi-layer optical film parameters is proposed, which is based on observation of quasi-waveguide leaky modes. As an example, two liquid layers separated by a glass slide and sandwiched between a prism and another slide, were studied. Leaky mode mlines of the two layers were measured, and used for calculation of the parameters of the two layers. The errors of refractive index of the measured film and the thickness are about ±0.001 and ±0.1μm, respectively.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 10 953 (1987)
Four-wave mixing used in optical amplitude encoding
Guo SIJI, and ZENG XIAODONG

The possibility of using transient four-wave mixing (TFWM) in optical amplitude encoding is studied theoretically. We developed an effective numerical method to solve coupled wave equations with discontinuous solutions, and to study the influences of system parameters on the quality of signal. It has been found that the TFWM system is suitable for encoding and it can generate high data rate communication signals.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 1 92 (1987)
The near infra-red confocal scanning interferometer
YUAN SHUZONG

In this paper, the scanning interferometer with confocal spherical cavity structure is described, which is operated round 0.85μm and 1.3μm respectively. The free spectral range of the interferometer is 4.3GHz, and the higest resolution is 36MHz (finesse is about 120).

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 1 87 (1987)
The deductive method of the light lock Moire fringe
CAO XIANGQUN, JIN TONQ, and FAN HUALIANG

This paper describes a deductive method of the light lock Morie fringe profile. This is more brief and pronounced concept than the method proposed by Japaneses. In comparison the theoretical calculated value with the experimental data, the results are satisfactory.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 1 82 (1987)
A match filtering method with high efficiency
YANG GUOGUANG, SU YONGGANG, and FU SHAOJUN

The physical justification of pattern recognition with a phaseonly match filter is analysed in this paper. In the experiment the amplitude of Fourier transform of object is modified to reduce the intensity dynamic range, while phase information is preserved. The holographic match filter was made by dichromatic gelation. The high emeiency correlation is obtained by using this method.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 1 78 (1987)
Three-dimensional reconstructure of neural cells on a computer
Wo MINCHEN, and LI QINXIUN

The ability of displaying stereograms on a computerized plotter has been applied to the 3-D reconstruction of cranial neural cells. We present in this paper the integrated digital constitutions of neural cells and the way of plotting stereo projective maps according to the stereopsis principle. The method provides a flexible and straight forward way for the study of the structures and morphology of organic cells.

Acta Optica Sinica
Jan. 01, 1900, Vol. 7 Issue 1 74 (1987)
Filamentation instability of nonuniform intense laser light in plasmas
LI XINLIN, and XU ZHIZHAN

The filamentation instability of nonuniform intense electromagnetic radiation, which contains large-amplitude Gaussian intensity variations (i.e., hot spots), has been studied. The relations of this instability with the intensity and transverse scale length of the initial perturbation, and with initial plasma electron density have been calculated and discussed. The results indicate that the large-amplitude Gaussian perturbations superimposed on a linearly polarized plane electromagnetic wave will fall apart...

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 9 859 (1986)
An approach to optimization of optical tolerance for minimum cost
TANG JIUHUA, and YU WEIZHOU

An optimization model of optical tolerance is proposed to enable straight forward calculation instead of the usual tolerance-budget balancing by trial and error. The objective function, is the minimum fabrication cost of the optical system. A general expression relating the cost of component processing to the tolerance is obtained by fitting to existing data. The constraints are image qualities in terms of MTF and distortion. An example is given which has two variables and is solved by network algorithm.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 9 854 (1986)
A new X-ray analyzer crystal——trihydroxymethylaminomethane
SU GENBO, HUANG GONGFAN, and LI ZHENGDONG

According to the relation between crystal structure and X-ray diffraction property, a new analyzer crystal-trihydroxymethylaminomethane (TAM) lias been prepared. Its was found to have a stable physico-chemical property with characteristics such as mechanical performance, linear expansion coefficient and X-ray diffraction property better than pentaerythritol (PET) crystal commonly used today. It has also been found that the TAM crystal is useful in practical applications.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 9 848 (1986)
Nonlinear optical coupling modes
LIAO CHANGJUN, and GEORGE I. STEGEMAN

Modes of coupling an external radiation field into an integrated optics waveguide, of which the guiding film is characterized by an in tensity-dependent refractive index, have been analyzed. Unlike the linear optical coupling, the transfer function is not a constant through its coupling area in a nonlinear coupler. The coupling efficiency can be increased by contouring suitably the layer of the nonlinear material in the coupling region.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 9 842 (1986)
A new hypothesis for origin of light formation during earthquake
ZHENG LIANDA

The earthquake light has long been supposed to be a phenomenon of atmospheric discharge. But it can hardly explain the fact that the earthquake light exhibits many colors and may occur in the sea. This article suggests that the earthquake light is not caused by atmospheric discharge but is a direct radiation from the fault rocks when they arerubbing each other. This new hypothesis oan explain many phenomena that cannot be explained by original suppositions.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 8 763 (1986)
Evaluation of aliasing for sampled imaging systems
ZHANG BAOMIN

Based on the model of integral sampling theory, an important fact about sampled imaging systems is presented in this paper. Instead of the traditional OTF, the complex frequency analysis of the output image with a normal input of bandlimited continuous space speotrum of variable-bandwidth should be used to evaluate the sampled imaging systems acouratly and completely. An evaluation method of aliasing for sampled imaging systems and the theoretical basis of data processing are also presented.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 8 759 (1986)
Relativistic calculations of single-electron energy eigenvalues and X-ray energies of rare earth elements Ac, Th, Pa and U
ZHAO YONGFANG, WANG ZHEN, and PAN SHOUFU

The relativistic Hartree-Fock-Slater (HFSD) approximate method was used in calculating the single-eleotron energy eigenvalues and the energies of Kα, Kβ and Hβ X-rays of rare earth elements Ao, Th, Pa and U. Calculations were also carried out by taking account of the relativistio correction to the exchange potential. Our results are in good agreement with experiments (with an accuracy of 0.3%).

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 8 753 (1986)
Study of the orientation of molecules DASPI and PIC adsorbed on an optical surface
QIU PEIHUA, LI QUN, WANG WENYAI, and LUO YI

With a linearly polarized laser beam of wavelength λ= 1.06μm acting on the monolayer of the laser dye 2-(p-Dimethylaminostryry L)-Pyridyethyl iodide (DASPI) and the organic molecules N, N -diethyl-pseudoisocynanine chloride (PIC) on a smooth surface made of fused quarz or glass, the SHG by DASPI or PIG can be detected easily. By changing the direction of the linear polarization of the fundamental wave and ratating the substrate, we have found that axes (electrio-dipole) of both kinds of molecules are perpen.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 8 748 (1986)
A picosecond GaAs photoconductive switch
ZHU SHIDONG, YE ZIQING, HONG XICAI, and YIN YUYING

The development of a picosecond GaAs photoconduotive switch is reported. The switch consists of a miorostrip transmission line formed on Cr-doped semi-insulating GaAs with a small gap (-20μm) in the stripline. As the source of optical pulses used for preliminary evaluation of the switch, a synchronously pumped Rh6G dye laser was used. The rise time of the signal observed on a sampling oscilloscope was 120 ps and the FWHM was 230ps. We measured the dependence of peak voltage of the switched electric pulse on the energy of the incident laser pulse for a bias voltage of 30 V and incident energy range of 38~220 pJ.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 8 744 (1986)
Design of a fluorescence image multiplier used for examining carcinomas
XIA AIDI

This article describes the design principle, design method and characteristics in structure of a fluorescence image multiplier used to examine early intramural carcinomas or neoplasms. Its clinical values are also evaluated.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 7 667 (1986)
Computer simulated rate processes in continuously pulsed CuCl lasers
SHI BINXING, FUu YUNPENG, YU JAILEE, and PAN ZHIWEN

We have calculated the lasing process in a continuously pulsed CuCI laser with rate eqations and found that the calculation converges rapidly in the iterative procedure with a set of carefully chosen initial values. Therefore, solutions can be obtained on a microcomputer. The relation between the laser output and tube wall temperature has been studied. Eesults indicate that Cl~ anions are important for the laser output.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 7 660 (1986)
Dependence of thermo-optic coefficients of glasses on temperature and wavelength
PAN XINTANG, and QI YAFAN

The dependence of thermo-optic coefficients W of glasses on temperature and wavelength has been investigated. The results show that W increases linearly with temperature according to the equation Wλt = Wλo+θt, while it decreases which increasing wavelength according to the equation W2 = A0 + A1λ2 + A2λ2+A3λ-4+ …. It has been found that thermo-optic coefficients W of glasses at any temperature in the range from room temperature to annealing temperature and at any wavelength in the visible region can be calculated by these equations.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 6 573 (1986)
Application of iterative method in the design of high-efficiency multi-beam gratings
WU ZHOULING, LU DA, and JIN GUOFAN

HEMG (High-Efficiency Multi-beam Gratings) are widely used in optical systems as splitters. HEMG should have (1) high diffraction efficiency and (2) uniform intensities at each diffraction order. High efficiency is realized by making the phase grating. Uniform intensities may be attained by either W. H. Lee s PPM Pulse Position Modulation) or PWM (Pulse Width Modulation). However, when the number of the required uniform beams increases, or when we deal with certain kinds of 2-D HEMG, these two modulation methods will lose their effectiveness, and become either ???perfect or too complicated to be practical. In this paper, we introduce the iterative method to design HEMG. Some practical results are shown.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 6 567 (1986)
Spectral matching of color measurement detectors for color printing
ZHU DEKUI

The calculation of theoretical "screen effect " from the viewpoint of mutual matching of spectral tristimulus values of a CIE standard colorimetric observer with color negative films and color printing papers is described in this article. The corresponding peak value position, half band-width and peak value s allowance of Red, Green and Blue of color measurements of color negative films are provided. The metamerism analysis and error analysis for the color measurements of general wavelength values are given. The experimental results have boi'ne ont the analysis. Each peak value comforms to the data published by Kodak Co. and French Co., and is nearly equal to the data pxoyided by a foreign color printer. Our data will provide reference for workers engaged in color photography and research and design of photographic equipment.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 6 562 (1986)
Two-dimensional aberration-balancing and computation of phase compensation function for holographic wavelength demultiplexer
XU DAXIONG, XU ZUO, WANG BEN, and FU ZHIPING

Optimized parameters of the optical configuration of holographic wavelength demultiplexer (HWD) have been obtained with aberration balancing. The wavefront aberration caused by wavelength shift has been minimized. The image size of a point source formed by HWD was determined by ray tracing. To reduce the size of the image, we propose a phase compensation function to calculate the image size. The phase compensation could be achieved by Computer-Generated Hologram (CGH).

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 6 558 (1986)
A new technique of image processing with speckle encoding using a holographic lens
MU GUOGUANG, WANG XUMING, WANG ZHAOQI, and WU FAXIANG

The application of a holographic leng in optical information processing with speckle encoding is presented. The hololens used is made under optimum condition. As an example, experimental results of multi-image storage with speckle encoding using the hololens is given.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 5 476 (1986)
Energy levels of 5sns and 5snd Rydberg series of Sr
LU JIE, HU SUFEN, ZHANG SEN, and SUN JIAZHEN

The 5snd and 5snd Rydberg series of Sr were selectively excited from the 5s2 1So ground state by using two pulsed tunable dye lasers pumped by the harmonic of a Nd: YAG laser. Afterwards, the Rydberg atoms were photo-ionized by a third laser pulse. The energy levels and quantum defects have been measured for more than seventy Rydberg states of Sr.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 5 469 (1986)
Study of infrared reflection spectra of TGS-family ferroelectric crystals
LI SHICHUN, YANG XIUPING, ZHAO YUJIE, LI JAN, FANG CHANGSHUI, and WANG MIN

Infrared reflection spectra at room temperature have been investigated for TGS-family ferroelectric crystals, including TGS. DTGS and ATGSP. The observed lines are tabled and classified according to their wavenumber and modes. We have found that there is a line at 930cm-1 resnlting from PO43--ions group on the infrared spectra of ATGSP. This indicates that the phosphoric acid enters the crystal, replacing sulphuric acid.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 5 465 (1986)
A subnanosecond electro-optical switch drived by an optoelectronic GaAs switch
ZHU XINMING, and MAO HONGWEI

A compact optical switch has been constructed, which consists of two pieces of Cr-GaAs, a resistor and a KD*P crystal, and is controlled by mode-locked optical pulses. The open time of the switch is oontinuosuly variable from sub-nsec to several tens of nsec, and its responsive time is as short as 280 pseo.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 5 461 (1986)
A large-aperture equal-thickness-fringe Fabry-Perot interferometer
HE ANZHI, and YAN DAPENG

This paper discusses the principle of a large-aperture equal-thickness-fringe Fabry-Perot interferometer. Its merits include a relatively low requirement on optical material, high resistance to disturbance and vibration, and high accuracy of fringe location. A transient interferometer has been developed which has a large aperture and can operate in an environment with strong vibration. Interferograms of combustion flames and rocket exhaust plumes were obtained by using this interferometer.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 3 284 (1986)
Real-time vibration measurement by image holography and photodetection
WANG CE

A system for real-time measurement of vibration using image holography and photodetection is described in this paper. This system can be used to measure samples having rough surfaces with poor reflectance. The photodetection instrument required here is very simple. Some examples of the measurement are given.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 3 281 (1986)
Nonlinear enhancement effect of adsorbed layers of HPD and riboflavin biological molecules
QIU PEIHUA, LI QUM, WANG WENYAO, JIANG SHOPING, and LIAN SHAOHUI

Under the action of the fundamental wave of a laser with λ = 1.06/μm, the biological monoJayers of HPD and riboflavin molecules adsorbed on an optical surface can generate SH and TH signals. The beam divergence angle of SH and TH of the HPD layer is 1 mrad, equal to that of the fundamental wave. It is, however, different from that of the ribaflavin layer. The harmonic light beams diffuse into a wide angle.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 3 277 (1986)
Preliminary research of contact photolithography by using a UV excimer laser
LOU QIHONG, LU DENWU, QI JIANPING, and WANG REMWEM

Excimer laserg are noted primarily for their ability to produce high output powers at ultraviolet wavelengths. This ability has made them attractive for lithography application. Excimer lasers are many times more powerful than conventional deep-ultraviolet sources like xenon mercury lamp. An experiment of contact photolithography in the order of a micrometer was demonstrated by using an ultraviolet XeCl excimer laser. An X-ray preionized discharge pumped xenonohloride laser was used to expose a thin layer of resist. The la^er, whioh emits at 308nm, delivered 10MW of peak power in a 2×2 oma beam, A ehromeon-quartz mask with features ranging from 1,0 ?10 gm was employed, tfor contact photolithography. After optimization of the laser power intensity on the resist^ the best laser power intensity for contact photolithography was found to bo about 0.2.Jim2 under our experimental condition. The pattern on the resist shows that linewidths down to 1.5 μτα can be resolved, and 2 .5/xm lines can meet iihe requirements of LSI. This technique has great implications for phoiiolithography because is has high resolutions and ultra-fast exposure times.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 3 274 (1986)
Study of laser selective excitations of hematoporphyrin in the condensed phase
CHEN SHUCHUN, DAI FENGMEI, JIANG SHOUPING, and LIAN SHAUHUI

Using a tunable pulse dye laser, we have made experiments of laser selective excitations in the vibronio band and O-O transition band for hematoporphyrin in both ethanol and 1N HCl at 77K. We have obtained structural fluorescent spectra, which show obvious selectivity for the excitation wavelength. It was found that there are four kinds of isomers of HPD in ethanol at 77 K.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 3 266 (1986)
Power coupling between two neighboring graded-index single-mode fibers
WANG ZIHUA

Approximating fundamental mode of graded-index fibers by Gaussian-modified Bessel function, the power coupling between two neighboring graded-index single-mode fibers is calculated. Coupling coefficient formula is derived,curves of the coupling coefficients as a function of distance D with different F values,exponent g of power law-index are plotted. Comparing these results for step-index (as a limit of g = ∞) with Snyder s results which suit to step-index only, we see that Gaussian-modified Bessel approximation is better than Gaussian approximation in dealing with evanesent coupling problems.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 2 189 (1986)
Raman spectroscopic study of coordinations of aluminium,boron in Na2O-Al2O3-B2O3-P2O5 glasses
JIN YIFEN, JIANG DEHUA, CHEN XIANGSHENG, BIAN BEIYA, and HUANG XIHUAI

The coordination states of aluminium,boron in Na2O-Al2O3-BaO3-P2O5 glasses have been studied by means of Raman spectroscopy. The study shows that when boron,aluminium ions coexist in phosphate glasses, it is possible that boron iong form BO4 tetrahedra prior to aluminium ions, with the former having three or four coordinations,the latter having four or six.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 2 185 (1986)
Study on the spectral,lasing characteristics of R560
Wu ZHENGLIANG, SHU JUPING, and YANG GUANG

This paper reports the spectral,lasing characteristics of R560 using a XeCl excimear laser,a YAG:Nd laser as pump sources. R560 is one of the Rhodamines synthesized by this group. In our experiments a diffraction grating is used in the dye laser resonator as frequency selection element, which is at grazing incidence in order to minimize the line-width. In this way, we have obtained a linewidth of about 0.1 A. As it has good spectral characteristics, such dye can be used in practical lasers.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 2 181 (1986)
Ray traces in graded-index optical fibers
WANG AN, and LIU SONGHAO

Three optical invariants of graded-index optical fibers,the ray equation in a fiber cross section have been derived. Examples are given for several special cases. The results obtained here are in good agreement with previous theoretical calculations. The method,results are useful in designing refractive index profiles of fibers.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 2 176 (1986)
Statistical properties of an absorptive optical system driven by a partially coherent field
WANG LI, and HU GANG

The quatum-statistical properties of an absorptive optical system driven by a partially coherent field are investigated. As the coherent component of the input field increases from zero, the intensity fluctuation of the output light may be slightly enhanced, i.e., the output field becomes less coherent as the input field becomes more coherent. This abnormal behaviour is caused by the phase fluctuation of the input light. In the low noise limit, the location,value of the maximum of the second-order correlation function for the input field are given analytically by means of the Gaussian approximation. In the Jiigh noise limit, an explicit expression of the second-order correlation function is also obtained.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 2 169 (1986)
A point-diffraction holographic interferometer
ZHOU WANZHI, and LU ZHENWU

This paper describes a new interferometer-point-diffraction holographic interferometer. In this interferometer, a collimated beam from a He-Ne laser is divided into beams (reference and object beams) by a beam splitter; the lens to be tested is placed in the object beam with a pinhole at its focal point; another lens is placed behind the pinholt to collimate the outgoing beam and a holographic plate is placed at the position where the reference and object beams are over lapped. The pinhole is small compared with the Airy disc of the lens. After the hologram is processed, it is replaced at the original position while pinhole is taken away. The hologram is then illuminated bj both the reference and nnfiltered object beams so tlxat two interferogxams with the same distribution are formed in the object and referenoe beams behind the hologram. It is known by theoritioal analysis that this is an iBdieation of the aberration of the lens under test. The principle of this method is basically the same as thai; of a point-diffractions interferometer. But in the case of a point diffraotien interferometer, adjustment is very difficult beeau5e it uses a glass plate with a highly absorbing layer and a very small hole on it and one can not find its position easily. While if oar method is used ihere is no more adjustment diffiotilty provided that the replacement is correct. In the tranditional intexferometrio testing of a lenft, auch as Twyman-Greeii interferometer, a standard spherical mirror must be used to reflect the beam back. In addition Twyman interferograms are sensitive to vibration and temperuture. Our method, however, does not require a standard spherical mirror and can provide more stable interferograms. In addition,the same hologram can also be used in testing other lenses provided that their fecal points are exactly at the pinhole position. This method can be naed 111 testing of lenses, telescope and microscope objectives during their proceflsing or assembling. It has the merit of simple structure and easy operation.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 12 1130 (1986)
Analysis of kinetic model of double exponential fluorescence decay
CHEN WENJU, LIN MEIRONG, and JIANG HONGLI

This paper presents a simple and effective method for fitting and analysis of the kinetic model of double exponential fluorescence decay. According to four typical cases, we give the rules for selection and modification of decay parameters to get the best fit. In this paper, the judgment of correction of the model fitted by our method is also discussed. The calculation program of this method is simple and can be carried out on a microcomputer. It can be easily used in further.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 12 1124 (1986)
Experimental study of parametric dependence of radiation from a Raman free-electron laser
CHU CHENG, LU ZAITONG, SHI BUIGEN, and ZHANG LIFEN

Systematic measurements of a go out radiation signal from our Raman free-electron laser indicated a good agreement between experimental data and theoretical calculations. As a results, the optimal parametric region for the laser operation can be determined, making it possible to furthor improve the performance of the laser.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 11 1055 (1986)
Processing of lateral shear interferograms
LIU SHUGANG, and XU XIAOFENG

This paper deals with a new method for processing of lateral shear interferograms. An optimal reference sphere is introduced in the fitting process so that the testing result becomes more reliable and rational. In this way, the shear interferogram of a mirror is processed with results conforming with the actual situation.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 11 1050 (1986)
CARS spectrum of N2 and temperature measurement in C2H2/air flame
WANG DADE, and JIANG ZHANKUI

We have measured the spectrum of Coherent Anti-Stokes Raman Spectroscopy (CARS) of N2 in a C2H2/air flame and computed its theoretical spectrum. Based on the 30mparison between theoretical and experimental spectra, wo have determined the tempareture of the flame. It is in agreement with what we got by using the method of laser-exoited fluorescence of OH in the same flame.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 11 1043 (1986)
An optical system of PZT scanning Fabry-Perot interferometer for measuring weak optical spectra
WENG TAIMENG, YANG JIAJUN, YE HUI, and SUN CHANGXIAN

The sensibility of the PZT scanning F-P interferometer to the temperature is a serious problem for the stability of the optical system. Methods to solve this problem are suggested in this paper, so that the system can measure weak optical spectra.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 11 1039 (1986)
High power white light from gold-copper mixed vapor laser
ZHANG ZHIWEI, ZHOU PING, and TANG XINGLI

The characteristics of a gold-copper mixed vapor laser has been studied. The average power of the gold vapor laser obtained was 4W. Especially, white light average output power 3.85W is obtained from this laser. The ratio of three-wavelength output power (6278A, 5782A, 5106A) is 3:1:3. Their efficiencies are all more than 0.1%.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 10 960 (1986)
Shearing interferometric testing of an astronomical telescope with aperture of 1.56m
XU DEYAN

The principle and method of shearing interferometric testing of the major mirror of an astronomical telescope with aperture of 1.56m are described in this paper. Measurement results with 1/4 PV are obtained.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 1 93 (1986)
Space-domain filtering for computer generated hologram
Lu DA, Wu MINXIAN, and CHIN KUOFAN

Reducing carrying frequencies in computer generated holograms ia very important in constructing the graphs. We propose a new off-axis filtering method in the space domain, which is suitable for wavefronts with quadric term. In some cases, by using this method the carrying frequency can be reduced to about 1/3 of that used in conventional frequency domain filtering. Two sets of preliminary experimental results are shown.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 1 87 (1986)
Spectral and lasing characteristics of PBD series of UV laser dyes
SHAO ZIWEN, YUE CHUANHUA, PAN JIAXING, ZHOU YIMIN, and GAO ZHENHENG

This paper describes the characteristics of six laser dyes of PBD series which are compounds of 2-phenyl- and five of 2-(p- or m- substitued phenyl)-5-(4 -biphenyl-yl oxadiazoles. Two of them are new compounds that were synthesized by Nankai University. The ultraviolet absorption spectra, fluorescence spectra and fluorescence quantum yields of such dyes are given. Tuning curves of PBD dye lasers pumped by a nitrogen laser are measured, and the tunable spectral regions are found to be of 356 to 393 nm. The laser conversion efficiencies of all the six PBD dyes reported here are higher than those of existing laser dyes of PPO and BPBD. The PBD series dyes are suitable to be pumped by either N2 laser (377nm) or XeGl excimer laser (308nm).

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 1 82 (1986)
Three-mode laser action in an inhomogeneously broadened medium
LI XIAOSHEN, and ZHU SHIYAO

Lamb s quantum theory of lasers is extended to deal with the three-mode laser operation in an in homogeneously broadened solid medium consisting of four-level atoms. The master equation, the operation characteristics and the line-width of the three-mode laser are obtained and discussed. The relevant experimental result is explained and effects of inhomogeneous broadening are studied.

Acta Optica Sinica
Jan. 01, 1900, Vol. 6 Issue 1 76 (1986)
Augmented transfer matrices and flow graph structures for inhomogeneous media
MA JIAN, and WANG SHAOMIN

Taking radial and axial inhomogeneity of medium into consideration, we have obtained augmented transfer matrices and flow graph structures. As their applications we have studied the effect of air index gradient on laser alignment and the additional diffraction loss of laser caused by inhomogeneous pump. Results show that the axial index gradient can compensate the effect caused by radial index gradient in some cases.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 9 859 (1985)
Multiple-pass Raman gain cell and reflectivity measurement of resonator mirrors
CAI BANGWEI, and KUANG YIZHONG

A brief account of the principle of multiple-pass Raman gain cells (MPC) is presented. A simplified method has been adopted to measure reflectivities of mirrors of the resonator. The optimum transit number was determined to be 20.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 9 855 (1985)
The third-order nonlinear susceptibility of ga Ilium arsenide under irradiation of CW CO2 laser
LI ZAIGUANG, CHENG ZUHAI, ZHANG YONGFANG, and LI TONGNIN

The third-order succeptibility of recombination-type semiinsulating gallium arsenide was measured to be 8.3×10-7esu with a multi-kW CW CO2 laser. The value is in good agreement with the result calculated from the impurity energy levels of this material.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 9 850 (1985)
Detection of single photoeiectron on solid surface
ZHANG ZAIXUAN, PENG WEIXIAN, and YUAN YEQIAN

Primary photoelectrons were produced on a solid surface by radiation of a tunable double-frequency dye laser. Pulse-height spectra of the primary photoelectrons in the proportional counter are measured on a multichannel analyzer. A simple exponential-decay pulse-height spectra of single photoelectron was obtained when the laser intensity was made very low. In this way single photoelectron on solid surface was detected.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 9 846 (1985)
Transient rf optogalvanic effect of Ne at low pressure
ZHU ZHUBIAO, YAN GUANGGAO, and ZHENG YISHAN

Experimental results on transient rf optogalvanic effect of Ne at low pressure are presented. Since there is no cathode in a rf discharge, the cathode effects are eliminated, Absorption and fluorescence spectra of the sample obtained simultaneously on such apparatus illustrate that the direct photoionization by high-energy photons plays an important role in the optogalvanic effect.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 9 841 (1985)
Study of pulse duration dependence of laser-induced damages in optical materials
ZHANG MEIZHEN, and LI CHENGFU

Laser induced damages in Nd: glass and KDP crystal for pulse duration from 13 to 70ns have been studied. The results indicate that the electric-field threshold for the laser induced damages in transparent dielectrics is inversely proportional to the fourth root of the pulse duration.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 7 667 (1985)
Measurement of magnetic circular dichroism of magnetooptical materials
LIU GONGQIANG, GONG TING, and TONG LIANG

An experimental set-up consisting of a measuring device of magnetooptic rotation and a quarter-wave plate is used to measure the magnetic circular dichroism (ellipticity tanh θ") of (BiTm)3(FeGa)5O12 single crystal films and the change of θ" as a function of the magnetic field intensity H and sample thickness 2h. The measuring accuracy is 0.01°. Experimental results have proved that the imaginary part of magneto-optie rotation is also related to the magnetization intensity M just as the real part, and that it changes linearly with the sample thickness.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 7 663 (1985)
An optical bistable device based on Raman-Nath acoustooptic diffraction
LIANG GUIYUN, LU WANXIN, LU DEREN, and ZHANG XUANLIN

An optical bistable device based on Eaman-Nath acoustooptic diffraction is reported. Intensity curves of diffracted light from a Raman-Nath acoustooptic modulator are recorded. The bistability of the first-order diffracted light intensity as a function of the input intensity is presented. Three modes of operation are possible for this acoustooptic bistable device. As a potential application, the acoustooptical bistable device can be used as a multi-channel switch.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 7 658 (1985)
Stimulated Raman scattering of a new Raman gain medium-N2-in-silica fiber
WANG ZHAOMIN

In the paper, a measuring method of the stimulated Raman scattering (SRS) of diffused N2 in solid silica optical fiber is proposed. It is a new type of Raman gain medium-gas in glass. The dependence of threshold and linewidth of SES on the power of pump light is discussed. The output mode is measured when the transmission wavelength in the optical fiber is lower than the cut-off wavelength of the single mode silica optical fiber. In addition a week coupling mode between N2 and SiO2 molecules is observed in the experiment.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 7 654 (1985)
Determination of propagation coefficient for scalar modes in optical fiber
SUN ZONGJIAN

In the paper it is reported that using a prism-fiber coupler, the propagation coefficient βmn for scalar modes travelling in optical fiber can be determined by measuring coupling angles or positions of m-lines. Each scalar mode can be excited by varying the coupling angle. The so-called m-line corresponding to each scalar mode is coupled out of an output prism. Its characteristics are different from those of the m-line coupled out of a planar waveguide. The degeneration of βmn is shown on the m-line photograph. A good agreement is obtained between, the measured and calculated values of βmn.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 7 648 (1985)
Passive mode-locking of a XeCl excimer laser
CHENG XUSAN, LOU QIHONG, and WANG RUNWEN

Passive mode-locking of a XeCl laser is achieved by using PTP and naphthalene as saturable absorbers for the first time. In a compact laser cavity with "soft focus" arrangement, modulation of 90% and pulse train of 4~5 distinct 3-ns spikes are obtained. The total energy of mode-locked pulse is 6.3mJ with a beam spread angle of 2 m rad.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 7 643 (1985)
Probe beam used for diagnostic of laser-produced plasmas
MENG SHAOXIAN, ZHOU XIANG, and CUI YIFENG

A Raman-shifted fundamental probe beam at 1.115A in a CCl4 cell has been obtained. The beam was then frequency-doubled in a KDP crystal to 5575A. The probe beam can be used for diagnostic of laser-produced plasmas.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 7 640 (1985)
An optical model of suspended sand in the sea based on two-flow theory of radiative transfer in the sea
LIU ZHISHEN

In this paper, a simple optical model for detecting suspended sand concentration by remote sensing is proposed based on the two-flow theory of radiative transfer in the sea. This optical model is more accurate than the "Logarithm model", while its mathematics is simpler than the Monte Carlo method by H. R. Gordon. Experimental results obtained in a water tank are presented and compared with results of the proposed optical model.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 7 636 (1985)
Measurement of time-resolved spectroscopy of high-repetition-rate short-pulse xenon flashlamps
LIN WENZHENG, ZHUO MEIZHEN, and TANG XINGLI

In this paper, a method for measuring the time-resolved spectroscopy of high-repetition-rate short-pulse xenon flashlamps is described. Experimental results obtained with different electric gradients and operation conditions (simmer or no simmer) are given.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 7 631 (1985)
ADTF universal multifunctional optical design program
WANG YONGZHONG

A universal program for optical design is presented in this paper. The idea of assessment function in DLS method has been introduced into the adaptive method,and a new fuality index has been suggested for it. A discussion is made regarding scaling focal length, optimization of stop distance and saving the time for OTF calculation.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 6 570 (1985)
Effects of frequency detuning on coherent optical pulse combination and area evolution
GU MIN, and TAN WEIHAN

A computer simulation of the effects of frequency detuning on coherent optical pulse combination and area evolution in an absorbing medium is given. We have found that the pulse combination and break-up, as well as stable pulse area, disappear when δ≠0.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 6 565 (1985)
Newtype two-wave interaction in saturable dye
Hu QIQUAN, and LIN FUCHENG

We have observed a new-type interaction of two non-collinear laser beams with the same frequency in saturable dye solution-bis-(4-dimethyl aminodithio benzil) (BDN) and pentamethine cyanine. It differs from the four-wave mixing, the so-called transient self-diffraction and coherent coupling effects.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 6 562 (1985)
Determination of optical properties of superficial layers with ATR method
YANG XInLIANG, LI WEIDE, CHEN JIEWEI, and WANG WENZHEN

Optical properties of superficial layers on metal surfaces are studied by surface plasma waves. The optical coefficients are determined by fitting ATR spectra with results of theoretical calculations. A superficial layer will cause a shift and broadening of the ATR spectrum for the bare metal surface. Under experimental conditions presented in this paper superfical layers as thin as <5A could be measured.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 6 557 (1985)
Feature selection in cancer cell recognition by means of optical power spectra
ZHANG SHAOYING, and QUO LURONG

In this paper we discuss the feature selection in screening cervical cells by meang of optical power spectra. After analyzing morphological characteristics of normal cells and cancer cells and features of corresponding spectra, we have found the key for recognition. This feature alone can give a correct-recongition rate up to 94.5%, higher than the rate of 92% obtained before by using six features in a similar experiment[1]. We also present the relation between the correct-recognition rate and the dimension of feature space. The results indicate a fall-down of the correct-rate when the feature number Is increased improperly.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 5 475 (1985)
Reflection display of rainbow holograms
SHAN QIZHE, CHEN GUICONG, GU JIJING, and LIN TING

A reflection display method of rainbow holograms is discussed. A bright and sharp reconstructed image can be obtained by setting a high-reflectance metal film behind the hologram. A properly choiced bias transmittance of the hologram can lead to a diffraction efficiency close to or a little higher than that of transmission reconstruction. The distance between the metal film and the hologram should be determined carefully for a high-quality reconstructed image. Both theorectical analysis and experimental results are presented.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 5 470 (1985)
A laser system with a stimulated Brillouin scattering phase conjugating mirror
XU JIE, WU CUNKAI, WANG ZHIYING, and HE GUOZHEN

In this paper a new laser system with an SBS phase conjugating mirror ig described. It consists of a Nd: YAG laser oscillator, a laser amplifier, and an SBS phaes conjugating mirror. A polarization discrimination technique is used to completely couple out the backward conjugating wave from the laser system. Effects of Brillouin cell geometry have been studied experimentally. By using acetone (300mm in length) as the scattering medium, Q-switched laser output of 100 mJ which compensated phase distortion has been obtained.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 5 466 (1985)
Measurement of refractive-index dispersion of transparent films
ZHOU JIULIN

Combining a single-wavelength ellipsometer with a spectrophotometer, we propose a method to measure refractive indices of dielectric films at any wavelength. "With phase thickness of the thin film properly selected, the error of the measurement may be as low as <1×10-2, enough for the usual thin-film design and deposition.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 5 461 (1985)
Spatially resolved optogalvanic effect
WANG YUMIN, GUI ZENXIN, ZHANG SHUNYI, and FENG JIANZHONG

Theory of the spatially resolved optogalvanic effect in a CO-discharge positive column is given. The theory has been found to agree well with experimental results. Based on this theory, a new method for measuring spatial distributions of electron density (or gain) in positive columns of discharge by means of optogalvanic effects is proposed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 5 455 (1985)
Optical damage in channel-waveguide mode cut-off modulators
CHEN ZHENG

The chance to observe optical damages in mode cut-off modulators used to be rare, because little optical power could be coupled into near-cut-off channel waveguides. The coupling capability, however, was found to be higher in our newly constructed three-section hybrid mode cut-off modulator, in which observable optical damage occured. Therefore, in designing guided-wave devices consisting of Ti-diffused waveguides, not only their electric characteristics but also their optical-power carrying capacity should be taken into consideration.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 5 452 (1985)
Characteristics of optical systems with π-phase edge image
YANG JIAN, Wu SHUDONG, and WANG ZHIJIANG

Through analysis of π-phase edge image profiles, we obtain an incoherence factor x and propose an evaluation method for optical microscopes with evaluation parameter C. It has been found that the quality of the imaging system depends on a. Finally, comparisons are made between paramater C and Strehl ratio S. D.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 5 446 (1985)
Generation of laser pulse sequence with discharge
QIU MINGXIN, ZHEN YOXGJIAN, ZHOU ZHENGZHUO, and SHAO MEIZHEN

The laser self-ulsing modulation (LSPM) has been observed in He-Cd laser and the paramaters related to this phenomenon have been measured. The LSPM has been found to be intrinsically different from the laser noise caused by the moving striation. The suppresion of the LSPM is briefly discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 4 379 (1985)
Discussion on lateral-rotation shearing interference and its relation with lateral parallel shearing interference
XU DEYAN

In this paper, mathematical relationship among parameters of lateral-rotation shearing interference and possible important applications of this type of interference are discussed. The basic relationship between lateral-rotation shearing interference and lateral parallel shearing interference is also established. It is proved that a simple single-flat-plate shearing interferometer used for parallel beam testing may be used to replace the prism shearing interferometer for convergent beam.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 4 374 (1985)
A simple method for Zernike polynomial fitting in fringe analysis
LIU YUEAI

A simple method for Zernike polynomial fitting in fringe analysis is given. Though the method is still based on a Gram-Schmidt orthogonalizing technique, it is not necessary to orthogonalize the polynomials during fitting. The linear transposition of the covariance matrix of the polynomiala can work out the Zernike coeflicinces directly. So it offers a better algorithm to Zernike polynomial fitting.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 4 368 (1985)
A new-type zoom lens with large aperture
YOU YINGQI

The design features of a large-aperture zoom lens tor 35 mm motion picture camera are presented. A structure of a fixed part between two moving parts in order to correct astigmatism is discussed. A new-type zoom lens is given as an example. It has a range of focal length of 25~85 mm, a relative aperture of 1/1.4 and maximum angular field 67°~18°.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 4 362 (1985)
Transmission anomalies of aluminium foils irradiated by intense laser-produced X-ray radiation
LU RENXIANG, CHANG CHENGCHUAN, PAN CHUNGMING, and TANG YONQHONG

Anomalous nonlinear increasing in transmissivity of aluminium foils in the wavelength range 8~11 A has been observed. These foils were irradiated with the monochromatic X-ray radiation at about 5×102 W/cm2 generated by a high-power neodymium-glass laser.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 4 356 (1985)
Determination of polarization degree and vibration direction in a branch-selected CO laser
CHENG RUIHUA, LUAN SHAOJIN, SHEN HONGWEI, and TAN WEIHAN

A simple method for determining the polrization degree and vibration direction in a infra-red laser has been proposed based on the principle of which partially polarized light can be regarded as the sum of a polarized light and a unpolarized light. The experimental result has been given.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 3 285 (1985)
Speckle phase-shift holographic lens for information storage
FU ZIPING, and Hsu DAHSIUNG

A novel holographic optical element (HOE)-speckle phase-shift holographic lens for information storage has been proposed. It combines the Fourier transforming property with the property of the spatial spectrum intensity equalizing, thus simplifies the optical configuration for holographic storage. The fabrication processes of the planar HOE and the experimental results of a high quality information storage are given in the paper.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 3 281 (1985)
The profiles and transient divergences of Cu/CuBr and Pb lasers
WANG YONGJIANG, and XIA TIBJUN

A simple method for measuring the time and space distribution of the light pulse intensity is reported. The steric sensing profiles for Cu/CuBr and Pb lasers, which include some detailed struture of the light pulses, and the transient divergences of the light pulses have been obtained by using this method.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 3 275 (1985)
Nonrosonant two-mode laser action
LI XIAOSHEN, and ZHU SHIYAO

Lamb s quantum theory of the laser is extended to treat the two-mode laser operation in the homogeneously broadened medium consisting of three-lasing level atoms. Subsequently the mean photon number in steady state, the frequency-determining equation, and the linewidths are respectively obtained in the case of two-mode operation with equal detunings. The effects of detuning are discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 3 271 (1985)
BASIC program of Coulomb approximation for the calculation of atomic transition probability and its application
ZHANG TINGJIAN, and LIN FUCHENG

A BASIC program of Coulomb approximation for the calculation of atomic transition probability based on Trefftz s FORTRAN program is given. It is used to calculate the oscillator strength of Helium-like and Lithium-like isoelectronio sequences for the first ten elements. Oscillator strength and transition probability for heavier elements Cu Ⅰ and Cd Ⅱ, which are important in laser application, are tabulated. Branching ratio of some transitions for CdⅡ is calculated to obtain the charge transfer cross section for Cd-He II collision.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 3 266 (1985)
ThCl4-PbCl2-NaCl system infrared glass
DAI YISHeNG, Hu HEFANG, and GAN FUXI

The glass-forming region in the ThCl4-PbCl2-NaCl system and some properties of the glass are reported, and the structure of the glass is briefly discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 3 262 (1985)
Analysing whole-field filtering of specklegram in a partially coherent and optical processing system
FU ZIPING, and WANG BEN

A method to analyse the whole-fringe patterns of laser speckle interference in the partially coherent and optical 1/2 processing system is proposed. With this method we can improve the quality of fringe patterns, and find the zero order fringe as well as more than two groups of colour encoding fringe patterns in different directions. Experimental results are also given in the article.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 2 190 (1985)
Concentric CARS and CSRS in solid-state despersive medium
ZHOU FUXIN, HE GUANGSHENG, and LIU DUN

In this paper we report an experiment of concentric coherent anti-Stokes Raman scattering (OARS) and coherent Stokes Raman scattering (CSRS) achieved in the dispersive medium calcite crystal under certain properly designed condition.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 2 187 (1985)
Fluorescence spectra Tb3+, Tm3+ in phosphate glasses
QI CHANGHONG, GAN FUXI, and AN XILIN

Fluorescence spectra of Ce3+, Tm3+, Tb3+ in phosphate glasses are quantitatively measures in the temperature range of 80~300K. Time evolution of fluorescence spectra of Ce3+, Tb3+, Tm3+ doped glasses are presented and discussed in detail.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 2 182 (1985)
Monte Carlo calculation of time/space distribution of energy deposition in electron-beam-pumped laser
WANG RUQING

Time-dependent Monte Carlo method of the electron transport is presented and has been applied to the calculation of the electron-beam energy deposition in Argon in the laser. Spatial distribution of the energy deposition, which is dependent on the time, has been obtained.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 2 176 (1985)
A new analytic method for calculating waveguide dispersion of single-mode fibers
WANG ZIHUA, and ZHANG YILONG

A new analytic method is developed for calculating the waveguide dispersion of single-mode fibers by using its field distribution. For step-index single-mode fibers, a waveguide dispersion formula is deduoed which is more accurate than that given by Sansonetti [2].

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 12 1134 (1985)
Determination of pulse shape asymmetry in a CW synchronously pumped dye laser using the method of spectrum-resolved SHG correlation
BAO XIAOYI, GUAN XINAN, LU FUYUN, and YUAN SHUZHOUG

We have determined the pulse shape asymmetry in a synchronously pumped dye laser using the method of spectrum-resolved SHG correlation. In this paper, we first present the basic principle of spectrum-resolved SHG correlation, and then analyse the possibility of determination of the pulse shape asymmetry in a CW synchronously pumped dye laser by this method. The experimental results were found to be in good -agreement with the results of our analysis.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 12 1130 (1985)
Data analysis of infrared reflection spectra of LiNbO3 and other crystals
LIU YAN, and LIAO LIJI

Data analysis is made by using classical oscillator fit method with preliminary data obtained from a Kramers-Kronig analysis which leads to a rapid convergence of the procedure. It has been found that the procedure can be used satisfactorily for the analysis of infrared reflection spectra of both the crystals (such as α-quartz) with separated bands, and LiNbO3 with overlapping bands having remarkably different intensities. Even those spectra with weak bands fading into strong ones can be processed satisfactorily.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 11 1046 (1985)
Raman-scattering study of phase transition in LiKSO4 at low temperature
GU BENYUAN, YANG HUAQUANG, and LI CHENXI

Bansal et al. have reported that the LiKSO4 crystal undergoes a subtle structural phase transition at 201K while being cooled according to the temperature dependence of Raman spectrum intensity for some polar phonon modes. They found the low temperature phase to be C3v4. But their evidences were not enough. In the present work we report further refined Raman spectra in LiKSO4 at both 210K and 203K. After carefully analysing their variations and considering the correlation of space group symmetry, we were convinced that tlie pattern of tiie structural phase transition in LiKSO4 at 203 K is while being cooled. This phase transition seems to be associated with a rearrangement of two adjacent SO2 tetrahedra in the unit cell.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 11 1040 (1985)
Experimental study of factors affecting enhancement of SERS spectra
LING DEHONG, Gu RENAO, ZHU HANBU, and LENG YONGZHANG

We have studied the effects of several factors (electrochemical pretreating, potential applied on the silver electrode, and laser illumination of the silver electrode in aqueous electrolyte during the process of elecrochemical oxidation-reduction cycle) on the enhancement of surface enhanced Raman scattering (SERS) spectra. Experiments showed that electrochemical processing of the silver electrode is of benifit to the adsorption of pyridine molecules, and that the potential applied on the electrode and the laser illumination make it possible for pyridine molecules to be adsorbed on the electrode surface. The experimental results are discussed analytically.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 11 1035 (1985)
A 2-J pulse avalanche XeCl excimer laser
Lou QIHONG, DING AIZHEN, DONG JINXING, and WEI YUNRONG

Based on optimization of parameters of an avalanche XeCl laser, we have obtained output pulse energy of 2J/1·atm by using low-inductance capacitors and the laser discharge power supply.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 10 955 (1985)
Twist measurement of beat lengths of single-mode fibers
HUANG ZHAOMING, YAO SHOUQUAN, SHEN HONGYUAN, and ZHEN RUIRONG

Beat lengths of single-mode fibers were measured by determining the output polarization ellipticity εc of a circularly polarized beam of light incident on the twisted single-mode fiber diode laser and a 1.34μm Nd:YAP laser were used as monochromatic light sources. The advantage of this method is that preliminary determination of the position of the major polarization axis is not needed and calculations of beat lengths become very simple.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 10 951 (1985)
The pseudocoloring of an encoded phase-picture
ZHANG JINGJIANG, wAnG SHUYING, LIN DOHE, and PENG FANGLIN

This paper presents a new method for the pseudocoloring of an encoded phase-picture. It can be performed only with one white-black film and one step of encoding. process. The encoded film is transformed into a phaseencoded transparency, then it ig put on the input-plane of a white-light processor, and the density pseudocolor image is obtained on the output-plane by spatial filtering of the Fourier spectrum. The theoretical explanation of this method has been made and it is in conformity with the experiments. This method has been used in the processing of the films of astronomy, remote-sensing, biology, and medicine, and good results have Toeen obtained.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 10 944 (1985)
Density pseudocolor encoding of black-white images by non-silver recording medium
HUANG WANYUN, WANG HONG, and WANG FENGYU

Non-silver recording medium has been used for density pseudocolor encoding of black-white images. This density pseudocolor encoding method and its applications in geology are described here in detail. The preparation of the recording medium and its characteristics and also discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 10 858 (1985)
Transition state calculations of oscillator strengths of helium-like ions in spin polarization Xα exchange approximation
ZHU QIREN, SONG QINGFONG, and PAN SHOUFU

The paper aims to show obviously the advantage of spin polarization Xa exchange approximation for transition state calculation through systematic calculation of oscillator strengths of single-state and triple-state transitions in helium-like ions. This is the continuance of previous work by the authors.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 1 95 (1985)
Theoretic calculation of the oscillator strength of the first positive bandsy stem of the nitrogen molecule
TIAN XINGSHI

The set of criteria for selecting configuration function, presented in the previous paper[2], are extended from double-electron excitation to three-electron exoetation. The effect of other multiplicate states on the excited B 3Πg and A 3Σu++ states are excluded by using the projection operator. By means of CI method the oscillator strongth of the first positiue band system of N2 is calculated. The calculated value is 0.00198, being in good agreement with experimental values.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 1 92 (1985)
Characteristics of WO3 film with large area deposited by laser photolysis
SHEN GUANGPING, ZHOU ZHENZHUO, and QIN MINGXIN

It is reported in this article that WO3 film was deposited by XeCl laser photolysis for the first time. The area of the film is 1cm2 and the deposition, rate is 41 A/pulse, the Main characteristics of the film, including its composition and resistivity etc, have been measured.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 1 89 (1985)
CF2(3B1) produced by reaction O(3P)+C2F4
ZHOU SHIKANG, ZHAN MINGSHENG, QIU YUANWU, LIU SONGHAO, SHI JILIANG, LI FANGLIN, and YAO JIEXING

This paper reports the experimental results of the emission spectra and energy transfer of CF2(3B1) produced by reaction O(3P)+C2F4. Some new vibrational bands and Franck-Condon factors are obtained. The relation between the vibrational state distribution of CF2(3B1) and the flux of C2F4 are also given.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 1 83 (1985)
SHG study for anomalous properties of LiNbO3 crystal near 75 ℃
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The intensity of SHG vs temperature scanning curve of LiNbO3 crystal have been measured with an acostic-optical Q-switch Nd3+:YAG laser. The change of coherence length of Maker finger was used to research the anomalous properties of LiNbO3 crystal. Experiment result showed the coherencelength broadening anomalously near 75℃. This anomalous phenomena may be attributed to the anomalous variety of refraction index owing to some ions movement in crystal near 75 ℃.

Acta Optica Sinica
Jan. 01, 1900, Vol. 5 Issue 1 78 (1985)
Photorefractive effect induced by YAG:Nd3+ laser in LiNbO3
ZHANG CHUNYU, and WANG TINGFU

This paper reports our experimental results obtained by using high-purity LiNbO3 for photorefraotive effect which is induced by YAG:Na3+ laser beam. The spatial distribution of birefractive change have been measured. It is demonstrated that the spatial distribution of birefringence change is asymmetric. A plot of the photorefraotive as a function of various annealing temperatures and hold time have been measured. The induced changes in extraordinary Is 3-4 times as large as the ordinary index.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 9 860 (1984)
A new technique for extending ranges of aspheric surfaces test by computer-generated hologram
AN PEIJIAN

This paper discussed features of the interference type computer-generated holograms with wide fringes. A new "technique by using third order wavefront of the computer-generated holograms with wide fringes for testing aspherio surfaces has been proposed. It makes one possible to decrease the holographic fringe numbers about 62%. The feasibility and potentiality of the technique have been verified by the experimental result.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 9 855 (1984)
Condition analysis of image contrast reversal by using π phase filter
KANG HUI, LI ZHENGMING, Li BAOLUN, and SUN YUEJIN

A method of image contrast reversal by using π phase filter is theoretically analysed. Conditions for forming contrast reversal image in output plane by means of addition of phase factor e±iπ on zero frequency in frequency plane are discussed. Experimental results are given. This paper offers a theoretical base for using π phase filter in optical information processing.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 9 847 (1984)
Estimation for possibility of good or bad stability of luminous intensity by fuzzy probability
LI ZUOYONG, and WANG YUANJA

Based on the concept of fuzzy probability, this paper gives the results of estimation by fuzzy probability for the possibility of good or bad stability of luminous intensity of the luminaire.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 8 765 (1984)
Optical coherence modulation by A-O effect
DONG XIAOYI, ShEN QIUGIN, WANG JIYUE, and CHEN SHENLIN

The theory and corresponding experimental results of spatial degree of coherence modulation with ultrasonic standing wave which is controlled by electricity are reported and experimental curves are made under different transducer voltages. In addition, we have measured and probed the optical degree of coherence modulation by Lithium Niobate EO-crystal as a beginning work in this field.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 8 760 (1984)
Adjustment of image geometry error for synthetic aperture side-locking radar
YUAN HUIKUM

This paper reports the causes of image geometry error for synthetic aperture side-locking radar (SALE) and analyses of correcting principle with wedge-len. Eadar image geometry error is corrected with an amplifier of the wedge-len and more accurate radar image has been obtained.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 8 756 (1984)
Laser-Raman measurement of vibrational relaxation time of N2 at room temperature
HUANG RUIPING, CUI TIKJI, ZHANG SHOUWEN, and WANG HUI

N2 molecules at high pressure were pumped into v = 1 level with a high power CW DF laser as a result of pressure-induced absorption. Using an Ar+ ion laser as the source we measured the anti-Stokes Raman scattering and obtained the vibrational relaxation time of N2 at room temperature to be 0.46±0.30 sec?atm.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 8 752 (1984)
Crossed beam chemiluminescence of O(3P) +NO reaction
XIE XIAOXIANG, ZHANG LIMING, QIU YUANWU, and LIU SONGHAO

The crossed beam chemiluminescence of O(3P)+NO→NO2+hv elementary reaction has been observed. The ground state oxygen atoms are produced by a microwave discharge in O2. Continuous spectra in the 4000-9666A region have been obtained. Dependence of the emission intensities on the NO flux is linear. Assuming the reaction obeys adiabatic correlation, the "chemiluminesecence should be due mainly to the transition 2B1→2A1 of NO2 molecules. This experimental result is in agreement with the theoretical calculation by Grangi et al..

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 7 668 (1984)
A unify method for extinction processing in atomic absorption and resonant fluorescent spectrometry
LIN YINGRONG

This paper introduces a new method which can obtain the extinction value linear to the concentration for the atomic absorption spectrometry (AAS) and atomic resonant fluorescent spectrometry (ARFS). The modeling experimental results exhibit that the measurement sensitivity is increased obviously too with this method. When the ARFS instead of AAS is used, not only the expression covention of the measure in extinction value is retained and there are also the property which the continuous radiant source and the lower resolution, monochromator applicable in ARFS, thus this unify processing method of extinction data exhibits some potential superiority.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 7 663 (1984)
Spectrum analysis of human blood flow Doppler signals with a time-spatial converter
YING XUANTONG, GHEN HUIPENG, ZHAO HuANQING, JIA YUruN, and YE GUOFEN

A method for spectrum analysis of human blood flow Doppler signals with an amplitude modulated grating as a time-spatial converter is reported. The experimental results are consistent with the theoretical analysis. This method possesses the advantages of fast multichannel parallel processing and large capacity. The facilities are simple and compact.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 7 656 (1984)
Steady-state pulses in laser amplifiers
FU SHUFEN, and FANG HONGLIE

An analytic solution for small gain to the rate equations of a lser amplifier was obtained. The conditions of getting "steady-state" pulses, and the effect of pumping on deforming of the pulses were analyzed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 6 572 (1984)
Double optimization damped least squares method for automatic lens design
YAO DUOSHUN

In order to solve the problem of automatic optimization of the weighting factor in the DLS method for automatic lens design, the concept of the uniformizing factor of weight is proposed in this paper. The merit function could be made automatically out of false local minimum during optimization by means of automatic adjustment of the uniformizing factor of weight in the program. The program and a practical example are also given in this paper.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 6 566 (1984)
Influence of water content on lasing properties in Nd-phosphate glasses
LI ZHONGYA, CHEN ZEXING, and ZHANG JUNCHANG

In this paper, the influences of the residual water content on the fluorescence properties, lasing thresholds and efficiencies, and gains of the laser amplifers are studied in the Nd-doped phosphate glasses.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 6 562 (1984)
Stability of a ring cavity for colliding pulse mode-locking
XING QIRONG, ZHANG REBING, and WANG QINGYUE

Stability of a six-mirror ring laser cavity for colliding pulse mode-locking is analysed by using matrix method. A simple analytical result is obtained. The results are significant for disign and alignment of the ring laser cavity.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 6 558 (1984)
Spectrum characteristics of Pb1-xSnxTe tunable diode lasers
ZHANG WEIZAI, CAO GENDI, ZHU XUOCHUN, and WANG HAILONG

In this paper, the characteristics and parameters of the tunable diode laser fabricated by HUVG method are reported. At 12 K, the pulse threshold current density is about 370 A/cm2 and OW threshold current density is about 440 A/cm2. At 13K, current tuning rate is about 0.15 cm-1/mA; at 400 mA, temperature tuning rate is about 2.3

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 6 553 (1984)
The characteristics of light transmission and reflection of a mercury plate under the action of a ruby laser beam and the analysis of its mechanism
ZHENG CHUANSIAN, YANG SHOTJZHI, ZHOU YEWEI, and YANG GUANGNING

The action of a normal pulsed ruby laser beam on a mercury plate has been investigated. It was predicted from qualitative consideration that its oharaot eristics of light transmission and reflection depend not only on the light energy density butalso on the internal pressure of the mercury plate. The front part of the acting laser pulse was absorbed and the transmission light corresponded to the pulse-tail. The phenomenon observed in our experiments is helpfu] to intarpret the mechanism of light transmission through a meroury plate. This paper reports experimental phenomenon observed in our work and makes an analysis to them.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 5 476 (1984)
The measurement of in-plane scattering of the planar light waveguides
XU ZHBNGQUAN, and ZHANG YI

In this paper, an experimental set up and a method of measuring the scattering angle are introduced. The measuring method of the scattering angle is as follows. The guided light wave propagating in the waveguide is coupled out by a prism. The well known m-line can be observed. By measuring the distribution of the light intensity along the m-line, the line width which covers a region of -40 db from the peak of the curve can be read out. While converting it into an angle of slope of the light beam, the scattering angle is obtained. It has been found that the influence of the scattering on the profile of the to—line is not considerable in the region from 0 to -20 db. The segment of the curve coincides with the intensity distribution of the incident beam. On the oiiher hand, the intensity distribution of the incident beam can be considered as a Gaussian one. Thus we can take the segment from 0 to -20 db of the profile of the m-line as the intensity distribution of the incident beam and calculate its width at the -40 db region. Considering the intensity distribution of the incident beam, we redefine the scattering angle. Thus, the error of obtained result is reasonable.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 5 471 (1984)
The FM mode-locking Nd:YAG laser
LI SHICHEN, NI WANJUN, LI MING, and ZHANG ZHAOYUAN

The laser described in this paper is working in OW PM mode-locking operation. The mode-looking states have been separated in this laser. The stable operation for a long time has been obtained. The pulsewidth of the output pulse is 66 ps, and the bandwidth is 10.6 GHz. The stability of the pulse amplitude is ±3%. The average output power is 200mW. The maximum oscillation bandwidth is 15.6 GHz and the corresponding pulse width is less than 50 ps.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 5 467 (1984)
A laminate gradient index media plate with the property of the prism
QIAO YATIAN

This paper deseribes and discusses the equation of the tracing rays paths in a laminate gradient index media. The media plate has the some properties similar to the prism.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 5 463 (1984)
Mode selection characteristics of four-mirror resonant reflector
LU ZUKANG, and QIU WENFA

In this paper "wavelength-reflectivity" formula of four mirror resonant reflector, in which each surface is bare, are deduced with the method of separating multilayer dielectric layers characteristic matrix. Wavelength scanning characteristics of four-mirror resonant reflector are analysed. A reliable method of theoretical calculation is proposed for design and application of the four-mirror resonant reflector.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 5 457 (1984)
A study on theory of FTIR-Q switch
ZHANG ZHENXI, ZHANG ZHIYONG, and CHENG XIANGMIN

In this paper, a type of the frustrated total internal reflection-Q switch (FTIR-Q switch) was discovered and related classical formulas was proofed. It has been shown theoretically the feasiblity of FTIR-Q switch driven by the dual piezoelectric transducer.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 5 450 (1984)
Precise determination of refractive index at ultraviolet and infrared ranges
LIU NAITING, YAO ZHANG, ZHANG YOUMING, and ZHANG FENGMING

A method for measuring the minimum deviation angle and making the precise determination of refractive index of optical material from ultra-violet to infra-red is given. The region of wavelength are from 0.21 to 2.43μm. The dispersion formula of fused silica and CaF2 crystal have been evaluated. The measuring results coincide with the calculation very well. The measurements have been done by an instrument consisting of a reflective collimator and a GM-1 spectroscope. The accuracy is ±2×10 -5 when λ2 μm.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 4 381 (1984)
Calculations of oscillator strengths of lithium-like isoelectronic sequence
SONG QINGFENG, and PAN SHOUFU

Oscillator strengths of low lying excited states of Be?, B?, C?, N?, O?, F? and Ne? lithium-like isoelectronio sequence are calculated in terms of spin pola-rizated Xa methods and the results agree with experimental data.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 4 379 (1984)
Bistable optical devices using branched optical waveguide
SUN YUNAN, and CHUNG BAOAN

This paper represents a bistable optical device (BOD) using Ti-diffused LiNbO3 branched optical waveguide modulator which is fabricated in authors laboratory. The steady characteristic is analyzed and calculated theoretically. From the experimental results, half wave voltage Vx =9.0 V and maximum modulation depth= 46% are obtained. The calculated band width is about 5.5 GHz. The bistable hysteresis curves, critical curves, and the dull saturated curves are observed. They agreed well with the theoretical analyses and calculated results. The Improvements for this device are discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 4 374 (1984)
A method for measuring the total integrated scattering from laser mirrors
CHEN YISHENG

This paper presents a method of measuring the total integrated scattering (TIS) from laser films. Some experimental results obtained by weak signal phase look-in synchronism technique are given. This method can be used to study the surface micro-Structure of the optical components. The detective sensitivity of this equipment is better than 10-5, The TIS of about 1.5?10-3 for high reflectivity films is measured.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 3 285 (1984)
Single longitudinal mode operation of semiconductor laser with external dispersive cavity
ZHANG HANYI, YAO MINYU, XU ZHIZHI, and ZHOU BINGKUN

Mechanism and condition of single longitudinal mode operation of the semiconductor lasers with external dispersive cavity have been investigated theoretically and experimentally. Using multimode laser diodes with unooating facet as well as coating facet, stable single longitudinal mode is obtained under room temperature CW opera- tion. Its linewidth is less than 10-3 A(50 MHz) and the tunable range is 200 A. Single mode output power is more than the total power output of multimode with our external cavity up to 3 mW.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 3 278 (1984)
Methods and experiments for dealing with the solid state laser beam with lower order mixing modes by Gaussian-like distribution
YAO JIANQUAN, NING XIFA, and T. S. Fahlen

For solid state lasers with lower order mixing modes in which TEM00 mode is dominant and a few lower order modes are included, a method of dealing with the beam based on Gaussian-like distribution is presented. The beam of lower order mixing modes may be regarded as a fundamental mode Gassian beam expanded K times. (K is the multimode coefficient). Firstly, from the calculation of intensities and spot sizes of the mixing modes and the fundamental mode, the justification of this assumption is indicated. Then the calculating formulae for the beam characteristics of the mixing modes are given.. By Gaussian-like method, a typical oontinuous waye YAG laser is analysed and the region of the optimum oayitv length is found. After that, the experimental method of measuring the value of K is recounted. Finally, the coupling of the laser output beam with a fiber is discussed, the necessary parameters for the practical application are obtained.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 3 271 (1984)
Study of cathodic coloration in the function-optical films based on α-WO3
YU FANG

Phenomena of cathodic coloration in function-optical films based on α-WO3 in semisolid electrolyte and to the experiment result as well as their mechanisms are described.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 2 188 (1984)
Optical problems in the combination of a high-speed rotating mirror camera with shadowgraphic devices or a interferometer
LU ZENGPEI

In this paper, the optical conditions for the optimum combination of a rotating mirror camera with shadowgraphic devices or a interferometer are described, and equations showing the relation among the optical data in the optimum condition of the combination are given. When the camera is used together with the shadowgraphic devices, another equation in the paper shows that the product of the three main parameters (maximum frame size, diffraction resolution, resolution and sensitivity) is always a constant, and that -fche optical system should be designed to make the three parameters optimally match, finally, the optical structure suitable for the camera that is used to be combined with the shadowgraphic devices or the interferometer is a]so discussed hero.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 2 182 (1984)
Effects of the preparation technology on the germanium film properties
ZHANG BAOBEN

The effects of both film material and every step of preparation technology process on the germanium film properties was described. The optimal experiment conditions to obtain the germanium film is provided. Finally, the experiments showed that the germanium is a crystal which lightly dissolves in the water, and hence the piebald phenomenon in the germanium film during the long period of applications is explained.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 2 178 (1984)
K-ray coded imaging for laser-plasma diagnostics
OUYANG BIN, YU JIAJTN, and LU HAIHE

The fresnel coded zone plate imaging for diagnostics of the spacing distribution of plasma is reported. A few results of using this technique are given.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 2 173 (1984)
Experimental study of a hybrid TEA CO2 laser
CAI YINGSHI, YI JINGRONG, and NIU WANGING

Three sohemas of a hybrid TEA CO2 laser are disoribed. Five experimental results are given, which are the effect of the cavity length, the effect of the CW CO2 laser power, the output energy and laser pulse osoillogram, selected branch and pulsed discharge low pressure CO2 laser tube. All of the results are discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 2 168 (1984)
Making up kinoform by the method of scanning-exposure
WANG YUTANG, ZHENG SHIHAI, and GOU WEI

A method of scanning-exposure to make up kinoform has the following advantages: continuous sampling and simple device compared with the method of sample-exposure. A schema for scanning-exposure was not affected by the imaging system. This schema can be applied to kinoform with separable variable.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 2 164 (1984)
Spectral identification of CO laser by optogalvanic spectroscopy
GUI ZHENXIN, ZHANG SHUNYI, and WANG YUMIN

Spectral identification and resolution of CO laser at room temperature have been made by using optogalvanic signal of positive and negetive characteristics. This method has the advantages of Simplicity and high resolution.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 12 1131 (1984)
Investigation of optical gyration in α-AlPO4 crystals
XU BIN, LIU XILING, and HAN JIANRU

This paper presents the investigation of optical gyration in α-AlPO4 crystals. By polaroids, the gyration light interference pattern and "pa" helical pattern have been observed. The optical gyration rate and its variations with wavelength and temperature have been measured. It is pointed out that the optical gyration of this crystal is constrained by the rotation direction of Al-O and P-O tetrahedron and their variations with temperature.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 12 1125 (1984)
Additional aberrations for synthetical imaging of optical element arrays
WANG SHAOMIN, and ZHOU GUOSHENG

Based on synthetical imaging principle of optical element arrays[1-3] and demonstrations of some new types of arrays as pseudo-conjugators[7-9], a general expression of synthetical image aberrations have been derived in this paper. Then, an αβvδ condition for synthetical aberrations eliminated has been given and diffraction affect has been discussed. The results have been proved by experiments.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 12 1119 (1984)
Speckle reduction of rainbow hologram by incoherent holographic technique
YANG GUOHUANG, ZUO JIAN, and ZHANG JINJUAN

An incoherent rainbow holography technique has been developed. We recorded rainbow hologram of a diffuse object with spatial incoherent light and reconstructed it with white light. The experimental results show that this method substantially suppresses the noise of hologram and improves the holographic image quality. Therefore, this is a simple and effective technique for speckle reduction.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 12 1115 (1984)
Absolute measurement of grating diffraction efficiency
HUANG YONGKAI, ZHUANG DAKUN, and XU GENCHUAN

This paper discribes a new method of measuring absolute diffraction efficiency of a grating. The main advantage is that the measurement precision is increased by using multiple diffraction. The experimental setup and results are given. Under nonoptimum conditions the measurement uncertainty is less than 4×10-3.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 12 1111 (1984)
Analytic solutions to the misaligned flat mirror resonators-Applications of the multiple-scaling perturbation theory to optics resonators
PANG HONGLIE, and WANG XIAOYI

In this paper the equivalent differential equation to the integral equation of misaligned flat mirror resonators is solved by using of the multiple-scaling perturbation theory. A complete analytic solutions to the equation is obtained for the first time.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 12 1107 (1984)
A simple AC liquid crystal light valve
CHEN KEN

A simple AO liquid crystal light valve is described in this paper, which consists of two parallel glass plates with electrode film on each side, enclosing a CdS photoconduc-tive film prepared byevaporation, a nematic liquid crystal layer and a dielectric mirror. By placing the cell between apair of crossed polarizers, projecting a white light image on the write-in side of the valve and using He-Ne laser as read-out beam, a incoherent to coherent image converter system is established and a coherent image with several gray scale can be obtained.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 11 1051 (1984)
Measurement of ESI parameters for single mode fiber
ZHANG YILONG, WANG ZIHUA, and CHEN ZHENYI

A simple method for measuring equivalent step index (ESI) parameters of the single mode fiber is presented. ESI parameters are obtained by measuring spot size at certain wavelength and cut-off wavelength; and by measuring spot sized at two different wavelengths. The theory and method of measurement are described and the typical experiment results are given.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 11 1046 (1984)
Temperature and heat radiation sensitivity of a single-mode fiber interferometer
HUANG ZHAOMING, and YANG XIAOJIANG

A Maoh-Zehnder interferometer using single-mode fibers has been built, and its temperature and heat radiation sensitivity has been investigated. The results are that the temperature responsivity and the heat radiations responsivity are about 110 rad/m℃ and 3.7 × 10-5 rad/m erg respectively. In heat radiation measurement, the absorbed heat radiation energy in the optical fiber is estimated to be 5-8% of the total energy passing the receiving area.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 11 1043 (1984)
Absolute calibration of X-ray films using low-energy radioactive source
FAN PINZHONG, and MAO CHUSHENG

With Si(Li) X-ray energy spectrometer, the intensity of low-energy radioactive source 55Pe has been measured and the absolute characteristic curves of emulsion for 5F medical film and Kodak No-screen film under the condition of 55Fe radiation have also been obtained using time-mark exposure technique. When the optical density D of 5F film is equal to 1, then the corresponding exposure H is equal to 12 × 107 photo/cm2.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 10 956 (1984)
Laser-induced fluorescence of long chain molecular (C6H10O5)n
ZHAO JIRAN, CHEN SHUQIN, and JIANG MINHUA

The long chain molecule (C6H10O5)n is excited by 1.06?m high power picosecond laser pulse chain. The molecule absorbs two photons, and the peak wavelength of the fluorescence spectrum is at 5600 A. The polarization characteristics of the spectrum and the dependence of luminescence intensity on the excited intensity are measured.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 1 93 (1984)
The solution of the ray-path differential equation in the axial gradient-index media
QIAO YATIAN

The exact analytical solution of the differential equation of the ray-paths in four axial gradient-index media is given. It has been indicated that the power for the axial gradient-index media plate is zere.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 1 89 (1984)
VUV spectra of HT-6B Tokamak
WEI LEHAN, FU JIKAI, and WANG SHUYA

The VUV emission spectra of HT-6B tokamak from 43.0 to 130.0 nm are photographed. The spectrograph used is model 247 grating incidence spectrograph. More than one hundred spectral lines have been identified. Besides Laman series of hydrogen which is the working gas, almost all lines are those of light impurities, i. e. oxygen, carbon and nitrogen. The spectral lines of sulfur are found firstly. The reason of exist of sulfur is explained.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 1 84 (1984)
The performances of CO2 mixing gas dynamic laser studied by an instantaneous mixing model
YAN HAIXING, and XU JIHUA

Basing on the gradual mixing model, the authors present a simpler instantaneous mixing model, with which quite a number of digital computations for nonequilibrium flow of CO2 mixing gas dynamic laser are carried out. The effects of velocity, temperature, concentration and radiation fields on the laser performances are studied. The variations of laser performances with these important parameters are given.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 1 79 (1984)
High-efficient X-ray analyzer crystal-meta-nitroaniline
SU GENBO, and HUANG GONGFANG

It s found that the (040) plane of m-NA(C6H6N2O2) crystal exhibits an anomalously high reflective intensity which is about 2~3 times as much as that of commonly used X-ray analyzer-the PET crystal. It is expected that this new crystal is a potential excellent material for X-ray analyzer.

Acta Optica Sinica
Jan. 01, 1900, Vol. 4 Issue 1 75 (1984)
Electrical signal produced by Nd-glass laser radiation breakdown of a ceramic thin plate
ZHENG CHDANXIANG, ZHOU YEWEI, YANG SHOUZHI, and XIE JIAN

Focusing a normal pulsed Nd-glass laser radiation on an nupolarized PZT ceramio thin plate, there was no electrical signal was observed between the two surface silver electrodes of the sample before the laser radiation breakdown through the sample. However, as soon as the breakdown of the sample happened, a pulsed electrical signal occured between the two surface-electrodes. The connections of the two electrodes remained unchanged in cases of the laser radiation irradiated the sample from either its front or back surface, the polarities of the produced electrical signals would be opposite to each other. When a hole penetrated on the sample was very small, the polarity of the signal was opposite to incident direction of the radiation. However^ when the hole became big enough, the polarity of the signal would turn to incident direction of the racliafcion.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 9 861 (1983)
Mode coupling in a double-frequency compound cavity dye laser
LI SHIQUN, ZOU YINGHUA, and XIA ZHONGJU

In this paper the mode coupling equations are used to study double-frequeney dye laser with a compound cavity. The double-frequency stable operation condition, the condition of inhibiting broad-band oscillations and the intensity ratio of two frequencies are deduced. Using a graphical method it has been found that this kind of laser has four typical tuning processes and some parameters can been conveniently obtained. Two new designs for double-frequency flashlamp-pumped dye laser with a compound cavity are discribed. The experimental results agree with, the theory on the whole.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 9 853 (1983)
Image reconstruction of phase conjugation by BSBS in an optical fiber
YANG TIANLONG, and YAO BINGZHONG

The image reconstruction of phase conjugation by BSBS in a multimode optical tiber has been studied experimentally. The image reconstructed by BSBS is approximately corresponding to the phase-conjugated image of the incident laser. The Stokes frequency shift is about 38.6 GHz.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 9 850 (1983)
Quality improvement of laser speckle patterns by the method of changing aperture
ZHAO DEXIN

This paper puts forward a method of taking a laser speckle pattern interferential photograph recorded by two apertures (an annular and biannular aperture). It gives more homogeneous diffraction halo of distribution of light intensity and better Young s fringes image.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 9 846 (1983)
Laser induced damage in some glasses at different wavelengths
DENG HE, and LI CHENGFC

The laser induced damage thresholds in some silicate and phosphate glasses at the fundamental, second harmonic and third harmonic of neodymium laser wavelegnth have been measured. It is found that the damage thresholds sharply decrease as the laser wavelength shortens. This experimental result shows that the laser induced damage in these optical materials is dominated by multiphoton ionization mechanism.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 8 766 (1983)
Measuring visual acuity with holographic grating
XU DEYAN, WU SHUDONG, and WANG YONGUNG

A method of measuring visual acuity with holographic grating is described. The measurement may be performed with a slightly modified conventional ophthalmoscope.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 8 762 (1983)
Analysis and treatment of Hadamard transform measurement for the case of being data short
ZHANG BINGQUEN

The error of evaluation of Hadamard transform measurement for the case of being data short is analysed and a formula is deduced. It comes the conclusion that when data are not complete one can make up the absent data by rand on values within the interval between the maximum and minimum readings of the data in hand, and decoding by computer, one can get the information of the spectrum in appropriate accuracy.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 8 758 (1983)
Study of the fluorescence characteristics of para-terphenyl vapour
ZHANG FUGEN

The fluorescence characteristics of the para-terphenyl vapour have been studied systematically. Its absorption, fluorescence and spectra have been measured. The fluorescence quantum yield is dependent on temperature, concentration and especially exciting wavelength. We explain the unusual fluorescence characteristics of organic scintillator represented by para-terphenyl in terms of "The effect of de-cage and inner-rotation". The first order of the Stoke s line of stimulated Raman scattering of KrF laser in hydrogen gas and the second order of the Stoke's line in methane have been used to pump para-terphonyl vapoux. No laser output was observed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 8 752 (1983)
Colour centres in LiF crystal-passive Q-switching in ruby laser
ZHANG GOIFEN

Using a LiF crystal with colour centres as passive Q-switch in ruby laser, a giant pulse laser output of 50 mJ with pulse duration of 30 ns (FWHM) is obtained. It is compared with that of using cryptocyanine dye as Q-switch.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 8 748 (1983)
Microinterference diagnosis of the laser plasma density profile
XU YUGUANG, CHEN SHOUHUA, and RONG ZHONGHUA

In this paper, the experimental arrangment for measuring laser-plasma density profile is presented. It consists of two parts: a laser system and a interferometer. The two arms of the interferometer can keep equal optical pathes automatically, when time resolving power of a interference diagnosis is demanded to be very high, it is very convenient to use this arrangment instead of precise and complicated adjustment.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 8 743 (1983)
Performances of the two-prism beam expanding system in dye laser resonator
ZHANG GUOWEI

Various performances of the two-prism beam expanding system in dye laser resonator are studied. The system possesses not only good beam expansion and collimation for the laser beam, but also good filtering and tunning functions. The angular dispersion formula of the two-prism beam expanding is derived and proved in theory, by using a tunning resonator composed of such a system without etalon, the narrowband tunning laser output with bandwidth ~GHz (~0.001 nm) can be achieved. The laser output bandwidth <4 GHz is experimentally obtained. The theoretical basis (angtilar dispersion formula of a multiprisms system) for getting <1 GHz narrowband laser is given too. In addition, advantages of the double(mixlti) prisms system-small reflection loss, polarization operation, easy adjust are analyzed. It indicates that two(multi)prisms beam expanding system is on ideal optic component with multifunctions (expanding, filtering and tunning).

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 7 667 (1983)
Study of imaging performance of high speed raster photography
YUAN YIQIAN

This paper describes and analyses the imaging performance of high speed raster photography with two dimensional pulse functional array. The lenticular plate has been used in the optical system to get the point-array-image of the raster plate which corresponds to the object. The density distribution of the point-array-image was measured. The resolution of the raster image is relative to the pitch of the raster plate. The high speed raster photography can obtain the higher relative brightness and lower resolution of image as compared with the conventional high speed photography. The frame interval is equal to the size of the image point. For conventional high speed photography^ a frame inteTyal must be larger than the height of frame. So "that raster photography can reach high framing rate. By reducing the frame size of ihe raster image, one can increase the resolution of the image.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 7 663 (1983)
The simple methods for determining film refractive index of optical slab waveguides
JIN FENG

Two simple calculation methods, i. e. analysis and extrapolation methods, for determining film refractive index of the optical slab waveguides have been presented in this paper. When the film thickness and substrate index are unknowen, these methods can be used to determine film index accurately using the simple four fundamental operations of arithmetic based on linear dependence of the film index upon mode indices.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 7 656 (1983)
Real-time display of the speckle vibration measurement with liquid-crystal
CHEN JUN, and LONG HUAISHENG

Principle and arrangment for real-time display of in-plance vibration by speckle method with the aid of liquid-crystal valve is presented. White light is used as the writing beam and He-Ne laser as the reading beam. The preliminary experimental results are given. The amplitude calculated from the real-time displayed Bessel fringes is in good agreement with the actual one.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 7 651 (1983)
Re-discussion on the reticle method for measuring the parameters of Gaussian optical spot
YIN DAREN, and XU SHENLONG

Suppose a optical spot is of a Gaussian intensity distribution and is modulated by a sectored reticle, then the parameters of this optical spot can be exactly derived from measurements of the harmonic amplitude spectrum.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 6 573 (1983)
Optical absorption of silicon under CW CO2 laser irradiation
LI YUANHENG

Basing on the Fermi statistical distribution of electron and hole in semiconductor silicon, the dependence of the transmittance of silicon under CO2 laser irradiation on temperature has been calculated, furthermore theoretical results were proved by experimental data. It has been shown that silicon can strongly absorb energy of the beam under intense CO2 laser irradiation, the mechanism of the absorption is dominately absorption of the free carrier.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 6 568 (1983)
Using a synchronous optical probe to diagnose the temperature distribution and the effects of radio ponderomotive force in laser plasma
CHEN SHOUHUA, XU YUGUANG, and BONG ZHONGHUA

When a optical probo-beam is scattered by a plasma with high temperature and density, it is easy to separate the ion component from the electron conponent of the scattering spectrum. Thus, the plasma temperature distribution can be measured. Besides, the plasma electron density distribution has been measured using a interferometer. The results show significant effects of the radiative ponderomotive force.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 6 562 (1983)
The study of reflective film at multiple frequencies
SUN LIANCHUN, LIU YAHUI, and BAI JIXUN

The necessary and simple condition for obtaining high reflectivity at multiple frequencies has been further derived, and the general form of the multilayer system and the corresponding formula of controlling wavelength are given in the paper. To be an example, the computed transmittance curves for multiple-frequencies (2 ×, 3×, 4×, 5× ) are shown. We have experimentally studied the system of 2 x frequencies, on which the transmittance curves are presented.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 5 476 (1983)
MTFA and characteristics frequency
SHA DINGGUO, and ZHANG BINGXUN

The feasibility of MTFA (modulation transfer function area) for assessing imaging quality of visual telescopic systems is described. A method for simplifying the MTFA has been discussed briefly. The way for characteristics frequency selection by using linear regression analysis is presented. Through the MTF measurements of several 8 ? 30 telescopic systems the regression statistics have been obtained from the measured curves. We found that the characteristics spatial frequency may be chosen in a wider range. The optimum frequency is close to the half limit frequency. A simplifying scheme for the parameters used in MTF measnremeiit, i.e. wavelength, field angle, azimuth and dioptric, is also presented.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 5 470 (1983)
An approach to the ruling of special circle-dividing gratings
ZHU JIBIN

In this paper, some special measures based on the grating photoetehing technique are presented. The ruling of circle-dividing gratings with optional fringes, quadruple frequency and absolute zero has been carried out in this manner.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 5 466 (1983)
Preparation of CdS photoconductive film used in AC LCLV and the measurement of its properties
CHEN KEN, and ZHONG QIMING

A method of preparing CdS photoconductive film used in AC Liquid Crystal Light Valve (LCLV)is developed. It employs general evaporating techniques in the vacuum system. After evaprating, the, CdS film is annealed at high temperature and diffused with proper Cu impurity as acceptor. Thus a CdS film with smooth surface, high dark resistance and well photocondactivity is obtained. It has been known by the measurement that the dark resistance is higher then 109Ω.cm. The ratio of light to dark electrical current is of the order of 10s, the response time ia shorter than 100 ms.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 5 462 (1983)
Index profile and imaging of a gradient index plate
ZHU SONGLAI, and YIN ZONGMIN

The paper has investigated a gradient index plate produced by ion-exchange technique. The index profile of the plate, the characteristics of light propagating and principles of imaging in it are discussed. Some interference fringe partterns and the photographs taken by the plate are also presented in this paper.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 5 456 (1983)
Paramagnetic colour center induced by γ-ray irradiation in phosphate and fluorophosphate glasses
FU WENBIAO

In this paper, a study on the properties of colour renter in phosphate glasses and polynary fluorophasphate glasses, which contain alkali and alkaline earth metal elements,using ESR method is presented. The experimental results show that there are two types of colour center in such two kinds of glasses, after irradiation with ?-ray. One is the trapped electron type, other is the hole type. Their g values are from 2.123 to 2.004. Hyperfine interaction of colour centers with phosphate nucleus (P31) has been observed. Analysis shows that the covalent bond in phosphate glasses; is stronger than that in fluorophosphate glasses. According to the orbital hybridization theory, the bond angles at the site of the defect in phosphate glasses are calculated.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 5 450 (1983)
Experimental research on optical properties of high temperature air in shock tube
LI HONGDE, LUO JUNE, and LI SIWEN

This paper mainly presents the experimental research on the optical properties of high temperature, low density air using a 800 mm diameter shock tube and a radiometer. The experimental temperature ranges over 4380~7500K; the density ranges over 1.41×10-2~1.00×10-1 ρ0 (ρ0 is the standard density at sea level). The spectral wavelengths are 430.0, 540.0, 640.0, 720.0 and 1038.0 nm. The experimental results are compared with the theoretical and experimental results published by other countries and shown a good coincidence. The characteristics of flow field are given and the reliability of experimental results is analysed too.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 4 380 (1983)
The effect of axial gradient index lens
CHEN YAOSHENG

The paper presents a derivation of the locus equation of rectangular waveguide of which index distribution function is n(x) = no (1 - 1/2 Ax3). The locus of light rays can be described with logarithmic function as incidence plane is the central plane having refraction index no, and tne locus of light rays can be indicated with arc tangent function as incidence plane is in edge which has index of n(X). When tangential plane crosses no plane, the locus of paraxial rays locating in tangential plane is a well-known sinuous function. According to the locus equation^ this waveguide has a function similar to parallel plate or divergent lens or cylindrical lens. When it is used as parallel plate, the waveguide offers much larger displaceiueiiii than that given by a parallel plate wMch made of homogenous medium. As a divergent lens, the waveguide can not be used as image-forming element, becaug? it only acts when light rays have a certain angle with optical axis. The image-forming feature depends on the distribution constant A, the central refraction index n0 and the thickness Z0 Thus, the locus line may locate in the outside or inside or end of the medium. The waveguide may be used in optical systems. The paper places emphasis on deriving locus equation of light ray motion in the inside of tho medium according to eikonal equation.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 4 374 (1983)
Application of Si photoconduction switcher to the measurement of the ratio of signal to noise and extinction ratio
ZHI TINGTING, and CHEN LANYONG

The radio of signal to noise of passive modelocked pulse in high power laser system and extinction ratio of Pockells electro-optical switcher have been measured using Si photocondution switcher. The position and amplitude of prepulses have been observed. It s shown that measurement methods axe simple, reliable and more sensitive.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 4 369 (1983)
Gain characteristics of XeCl laser
CHEN JIANWEN, Fu SHUFEN, Liu MIAOHONG, CHAo LimING, and GUO WEICHONG

This paper reports the experimental measurements of gain characteristics of a XeCl laser pumped by Blumlein fast discharge device, using the method of varing output coupling, according to the relation between output power of the laser consisting of a stable cavity and homogeneously broadended gain medium, and other laser parameters, such as small-signal gain coefficient go, constant absorption loss coefficient saturation intensity Is and cavity length finally, the optimum transmittance of laser is determined. Authors find that the optimum transmittance is a function of pumping power.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 4 364 (1983)
GaAs-(AlGa) As large optical cavity lasers
ZHANG XINGDE, and REN DACUI

GaAs- (AlGa) As large optical cavity lasers have been fabricated using liquid phase epitaxy method and its main parameters, have been measured, such as laser pulse power, beam divergence angle, wave length and external differential quantum efficiency etc.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 4 358 (1983)
The integration MTF and the spacial resolution of the pushbroom imaging system using the charge couple device
GU TIAVZHU

On MTF thoery of the pushbroom imaging system using the CCD line array, the formula which is used to calculate, respectively, the MTF in the line direction and in the direction perpendicular to the line direction has been given in some articles, under a special condition of pushbroom motion perpendicular to the line. In this paper author derives a general formula which is valid for any direction and any angle crossed by the directions of the line array and pushbroom motion.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 4 351 (1983)
Realization of image amplitude substraction based on Talbot effect
WANG WEIJAN, LUO YIZU, and ZHANG HONOJUN

A new method-realization of image amplitude substraction is described based on Talbot effect of grating with illumination of coherent convergent light. The theoretical analyses are made to explain the principles of the method, and the experimental results, which are in accordance with the theory are presented.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 3 282 (1983)
Optoelectronic GaAs switch controlled by mode-locked laser pulses
[in Chinese], [in Chinese], and [in Chinese]

A Cr-doped semi-insulating GaAs cube was used as the optoelectronic switching element. Using the ultrashort pulses at 1.06μm or 0.53/μm to control this switching element, its output characteristics was observed and the dependence of the switching efficiency on the laser energy was obtainded. The behaviour of the photoconductivity at high pumping level was analysed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 3 276 (1983)
A new method for the measurement of interference fringe shift
LIU YOUXIN

From the basic concept that an interferogram is a contour map in intensity, we present a new simpler method, for measuring the shifts of interference fringes. In this method, as long as a intensity profile is taken on any straight line parallel to the equidistant parallel fringes in the interferogram (or in the interferogram film), the shift of the interference fringe at all points to this straight line can be found and the variance of the physical quantity of interest is calculated thereafter. It allows the meastLring equipments and the automatic analysis to be simplified, and data can be taken at any pomt in tlie interferogram disregarding the position of fringes. Our experiments show that the repeatability error is less than 1.5%. Satisfactory results have been obtained when this method is applied to the measurement of refractive-index profiles of optical fibers with the nondestractive traverse interferometry. As compared with the results from reflection method, the error of the maximum relative refractive-index difference is about 1% and the whole profile curves accord well with eath other.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 3 271 (1983)
Sandwich speckle photography
JIN GUANCHANG, ZHANG WEIBAO, and LIU CHUNYANG

A new speckle photography method-sandwich speckle photography is proposed. The paper describes the simple principle of this method and it s advantages. Similar to tne sandwich holograhy, it makes up of two pieces of single exposure specklegram. We made each single exposure photograph at various situations, then put two of them together and precisely replaced them. The quality of fringe obtained by sandwich specklegram is quite the same as that obtained by common double exposure speckle. gram. If we make n pieces of single exposure specklegram n(n—1)/2 pairs of double exposure specklegram will be obtained. It is well-known that the double exposure specklegram is very difficult to make at temporal processes and dynamical deformation. High speed photography combined with sandwich speckle photography can overcome this difficulty. Finally an experimental evidence is identical with the result of double exposure. Doubtlessly, the sandwich speckle photography will pavo the way for the application of speckle intexferometry.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 3 265 (1983)
The effect of spatial filter on laser beam brightness
CHEN SEISHENG, BI WUJI, WANG XIAOQIN, and ZHAO QINGCHCN

This paper reports some experimental results on vacuum spatial filter in improving laser beam quality and increasing laser beam brighteness.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 3 259 (1983)
Improvement of flux uniformity in CO2 laser by laser beam rotation
ZHOU HANG, PAN SHIMING, XIAO MINGQIANG, and LI HAICHANG

A method of improving laser flux uniformity has been reported. Laser beam passes through a tilted germanium plate which rotates around the beam. The exit beam from the plate will rotate around its axis. In this way, the spatial uniformity of laser flux can be improved. The relation between rotation parameters and spatial distribution of laser flux intensity has been analysed and the experimental results are in agreement with the theoretical calculation.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 2 188 (1983)
Dissociation of SiH4 with CW CO2 laser excition
WU ZHENQIU, LIU HANGQING, and XU JIREN

The dissociation of lower concentration silane diluted with hydrogen has been investigated by OW CO2 laser excitation, and its mechanisan is analysed. The equation of dissociation rate and relationship between the rate and the laser power density is deduced. The experimental results are in accordance with theoritical analysis.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 2 182 (1983)
Procedure of determining the proper recording parameters of toroidal holographic gratings
ZHUANG KUI

A calculation method is developed for producing an aberration-reduced toroidal holographic grating used in a Seya-Namioka monoohromator. Procedure of determining the proper recording parameters is described. The theoretical results show the availability of the present calculation method.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 2 178 (1983)
A method of increasing diffraction efficiency of hologram
ZHANG JINGFANG, WANG MINZAO, and HA LIUZHU

In this paper a new approach so-called photolytic silver method is presented for getting a silver-particle phase hologram by bleaching an amplitude hologram into a silver-chloride hologram first and then exposing it to a beam of strong light. Using Tianjin type-I holographic plates, the maximum efficiency of 28 % has been achieved and the hologram is photostable. The fact that the electron microscopic images show that the dimension of photolytic silver particle reaches a limit, of 0.01 μm appears to explain the cause of increasing the diffraction efficiency.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 2 173 (1983)
Direct extreme monitoring method for narrow band interference filter coating
YIN SUBAI

A computer simulation of the monitoring process has been performed. It is shown that the direct-extreme-monitoring method has the best performance, provided that the spectral bandwidth of the monitoring light beam is narrower than the interval between the turning points, and the drift of control wavelength is lower than one-third of the above mentioned interval.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 1 93 (1983)
Diffraction efficiency of sinusoidal grating and lamellar one with shallow groove
CHEN NANDIAN

The article describes the approximate relation between incident angle and diffraction efficiency of the perfectly conducting sinusoidal grating and the lamellar one. The analysis in the article starts with electromagnetic theory. Solving the boundary condition equation of electromagnetic field, we give some approximation in order to make the equation solved easily; as a result, their complicated relation can be obtained under certain circumstances.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 1 88 (1983)
The characters of the transmitting laser produced in laser heating micro-balloon targets
CHEN SHISHENG, BI WUJI, WANG XIAOQIN, and HE XINGFA

This paper reports some measurement results of the characters of the transmitting laser light produced in laser heating micro-balloon targets. The transmitting images of the micro-balloon targets are transparent in the case of accurate focusing and small prepulse. But its images are muddy in the case of defocusing and larger prepulse. The measurement results obtained by using the spatial resolve spectrum show that the spectrum of the transmitting laser light passed through the plasma is broadened clearly, the broadened spectrum line is central symmetry to the spectral line of the input laser beam, the width of the spectrum is broadened from 0.2 nm to 5.0 nm.

Acta Optica Sinica
Jan. 01, 1900, Vol. 3 Issue 1 80 (1983)
Possibilities of improving the sensitivity and measuring accuracy for the Michelson interferometer
ZHU JIBIN

An improved design relevant to the traditional Michelson interferometer is proposed in this paper with a purpose of obtaining better sensitivity and measuring accuracy. This is an effective approach to improving the sensitivity and measuring accuracy under the same condition for the Michelson interferometer.

Acta Optica Sinica
Jan. 01, 1900, Vol. 2 Issue 6 573 (1982)
X-ray crystal spectrograph for the laser-plasma experiments
LU RENXIANG, MAO CHUSHENG, YIN GUANGYU, and SHEN HUAICHUN

X-ray spectral lines emitted by high temperature plasma can be taken by means of crystal spectrograph in laser-plasma experiments. Spaoe-integraied and space-resolved x-ray crystal spectrograph developed and used in onr laboratory are described in this paper. X-ray diffraction crystal is "the main pari of the speotrograpli。 The integratod roflection coefficient, peak diffraction efficiency7 crystal broadening and hoinogonoity of ihe crystal have been deiermined experimentally. In addition, linear dispersion and instrumeni broadening have also been estimated by some experiments. Tho oharao ieristio curves of the X-ray film have been obtained by several mothods. The windows of ihe spectrograph are aluminized Formyar films which, have high transmission in soft X-ray region. This is one of the distinguishing features of our spectrograph. Some typical space-integrated and space-resolved spectra of He-like and Η-like ions of sodium and silicon in 5~13 A obtained in our experiments are presented, in Lite end of this paper.

Acta Optica Sinica
Jan. 01, 1900, Vol. 2 Issue 6 568 (1982)
Optical fiber raster plate and its fabrication
YUAN YIQIAN

A new method of preparing the raster plate with optical fiber has been developed. The parameters and measurement result of the element of raster plate show that a total of micro-lenticular elements is 2.25?104. The pitch is 0.4mm. The photographic resolving power of the optical fiber raster plate for a single lenticular element is 110 line-pair mm-1, the focal length 0.3mm. The raster plate has total information capacity of 1.089×107 bit.

Acta Optica Sinica
Jan. 01, 1900, Vol. 2 Issue 6 564 (1982)
A study for F2 center ionized by light
WANG TINGJI, and ZHANG ZHISAN

The ionization of F2 center in LiF and NaF crystals are explored in this paper. Experiments show that F+2 centers are created in LiF crystals with F2 center when they are irradiated by Hg-lamp, pulse Xe-lamp and D. 0. carbon arc. And F+2 centers are created in NaF crystals with F2 center when they are irradiated by pulse Xe-lamp and W-lamp. The problems about the efficiency of two-step ionization are discussed in the paper. The analysis shows that the way of increasing the efficiency is: it is necessary

Acta Optica Sinica
Jan. 01, 1900, Vol. 2 Issue 6 558 (1982)
Matrix discussion of the effect of mis-alignment on path difference in stable plano-concave Fabry-Perot resonators
ZHU RUOGU

In this paper, the effect of mis-alignment on path difference in stable plano-concave resonators (sjmply called plano-concave cavities afterwards), whioh are widely used in practice, has been discussed by means of matrix methods. The method is suitable to the common spherical cavities in principle. For convenience of analysis, however, the plano-concave resonators are only discussed within miniature mis-alignment. After comparison with experimental data and theoretical results three conclusions are obtained: (1) When the plano-concave resonators are correctly aligned, the effect of mis-alignment on path difference will be the most sensitive. (2) The plano-concave resonators have the "self-alignment" effect within miniature mis-alignment, and the experiment shows that the path difference will fluctuate with increase of mis-alignraent angle. (3) If the angles of mis-alignment are less than 1", the effect on path difference for plano-concave resonators drop down to 3 χ 10一9, and if the angles of mis-alignment could be further reduced to 0.2", the effect on path difference will drop down to 1×10 10.

Acta Optica Sinica
Jan. 01, 1900, Vol. 2 Issue 6 552 (1982)
The polarization characteristics and mode competition experiment analyses of semiconductor lasers
ZHENG GUANGFU

This report describes the experimental researches on the polarization Oharaoteristios of symmetric GaAs-GaAlAsP double heterojunotion lasers, and analyses the mode-competition processes of these lasers. The experiments showed that semiconductor laser is emitted spontaneously and does not indicate optical polarization characteristic when it is biased under the threshold current. When it is biased above the threshold current, the laser for thin active layer of d = 0.15?0.40枓m ig generally observed only in fundamental order mode, and TE mode polarization is predominant. At this time, polarization selection is dependent on Fabrj-Perot cavity facet (cleaved face) mode reflectivity E0. But TM mode is saturated at the threshold, the onrrent applied to the laser above the -fclixesliold is used to enhance the TE polarization when the active thiokneas d is larger than 0.4^m, the competition, between TE and TM mode, fundamental order and higher order mode will appear. TE mode enhancement will result in TM mode decay, or TE mode decay provides TM mod? enhancement. In this case, polarization selection depends on both the mode confinement factor Γ and facet reflectivity Rm. TE mode, TM mode, fundamental-order mode and higher-order mode will possibly appear. Besides, polarization charaoteristio depends closely upon the internal crystal defect and inhomogeneous crystallization for the aotive layer of laser as well as the partition ratio of injected carrier.

Acta Optica Sinica
Jan. 01, 1900, Vol. 2 Issue 6 547 (1982)
Super-Gaussian photographic-plate apodizing aperture
ZHENG YUXIA, LIN ZUNQI, and YU WENYAN

In this paper, the results of super-Gaussian photographic plate aperture research are presented. The design and fabrication of this kind of apodizing aperture and it s results of practical application are reported.

Acta Optica Sinica
Jan. 01, 1900, Vol. 2 Issue 5 477 (1982)
The protective coatings on sodium chloride crystals
ZHANG BAOREN, and WU LIMING

It has been shown experimently thai the protective coatings of "F46" or "202" etc deposited on the surface of sodium chloride crystals by vacuum evaporation can endure continuous expansion of CO2 laser at 750 W/cm2,in addition to its merit of moisture proof effect.

Acta Optica Sinica
Jan. 01, 1900, Vol. 2 Issue 5 473 (1982)
The calculation of the optimum phase matching angle in SHG of LiCOOH.H2O
SONG CHANGLI, and WANG LUCHUAN

In this paper, the variation of the phase matching angle and the effective nonlinear coefficient versus the fundamental wavelength in a second harmonic generation of the lithium formate roonohydrate (LiCOOH ‘HaO)of the mm 2 type crystal are calculated. It is found that there is one (or two) optimum phase matching angle {θ, φ) for each fundamental wave, at which the second harmonic conversion efficiency is highest. Fitted formula for the variation of the phase matching angle versus the fundamental wavelength is obtained.Second harmonic generation for 0.53μ, 0.35 μ and 0.266 μ are observed from the crystals cuied at the computative angle.

Acta Optica Sinica
Jan. 01, 1900, Vol. 2 Issue 5 468 (1982)
Electric properties of piezoelectric ceramic thin plate under action of ruby pulse laser radiation
ZHENG CHUANXIANG, ZHOU YEWEI, YANG SHOUZHI, and XIE JIAN

Under action of normal pulse ruby laser radiation, electric properties of a piezoelectric ceramic thin plate of PZT system have been studied in our experiments. We have observed an unusual phenomenon before a small hole having been drilled by focusing laser radiation on the sample. When the laser radiation directs on it in either polarizing field (positive) or opposite direction (negative), we observe electric signals between two surface electrodes having same shapes and amplitudes, and their polarity is constant. As soon as a small hole has been drilled on the samples, in both sides above illumination cases, we observe eleotrio signals having jump changes in different ways, and one of them may be changed in polarity. This paper reports obtained experiraental results in our work, and makes a primary discussion to them.

Acta Optica Sinica
Jan. 01, 1900, Vol. 2 Issue 5 463 (1982)
The design and fabrication of wedge-ring detectors for optical power spectrum analysis
ZHAO HUANQING, DU YUANCHENG, ZHAO ZAIZHONG, and ZHANG ZHIMING

In hybrid optical power spectrum analysis systems, the wedge-ring array deteclor functions as an optical to electrical interface device for sampling the optical spatial frequency information for further processing by digit computer. The detector designed and fabricated in our laboratory consists of 32 semi-circular rings for detecting the radial information and with 32 wedge-shaped sections for the directional information in the spectrum. The detector is made on a silicon wafer diameter is about 32 mm with carefully controlled diffusion process in order to obtain uniformity in response and sensitivity. The average responsibility is about 0.5mA/mW for "the wedges and annular rings of ihe corresponding areas, the time constant is about 150 μθ. The spatial bandwid-fch could be up io 100 cycles with an optical transform lens of 240 mm fooal length irradiaied by ihe He-Ne radiation of 632.8 nm.

Acta Optica Sinica
Jan. 01, 1900, Vol. 2 Issue 5 458 (1982)
Thermo-optic properties of optical glass
HUANG GUOSONG, and CHEN SHIZHENG

In order to minimize the influence of environmental temperature on optical components, rhermo-optics coefficients W, P and Q that describe the variation of optical properties of optical glasses at a certain temperature are introduced. The methods of measuring some optical glasses in respect of their coefficients are described and the results are given. This paper ends with a discussion on the possibility of reducing the influence of thermal disturbance on optical components.

Acta Optica Sinica
Jan. 01, 1900, Vol. 2 Issue 4 380 (1982)
Optical and other physical properties of Al(PO3)3 contained fluorophosphate glass
JIANG YASI, JIANG FUSONG, and GAN FUXI

Fluorophosphate glass is used as a kind of optical glass and laser material. Based on studying the formation and structure of A1(P03)3 contained fluorophosphate glass, in the present work, the optical and other physical properties of the above glass have boon investigated. The low A1(P03)S content fluorophosphate glass,in which the network structure has been destroyed seriously, is located in destroyed region, the variation of the glass properties and the effect of various fluorides on the properties are similar to those of the oxide glass in destroyed region.The special role of LiF,MgF2,AlF3 is also reflected on the variation of the physical properties. Moreover, compared with silicate and borate glasses with high contents of glass formers, the electrostatic attraction between cations and anions plays more important role to variation of the properties of the fluorophosphate glass with low Al(P03)3 content. The position of the studied glass in n vs. v diagram is plotted, the partial properties of the studied glass are given and compared with some literature data, and the variation of the partial properties have been related to the Al (PO3) 3 content.

Acta Optica Sinica
Jan. 01, 1900, Vol. 2 Issue 4 372 (1982)
Acousto-optic diffraction in waveguides
SHI BANGREN, XU CHENGJIE, LI YUSHAN, LIU HONGJU, and LU PING

The acousto-optic diffraction experimental results of guided optical waves and acoustic surface waves in the Ti-diffusod LiNbQ3 waveguides are reported in this paper. Phe intensity of two TE modes (TE0, TEX) varying with the acoustic power is measured. For the zero-order beam, modulation approximate to 100% is obtained at 68 mW acoustic power. After simple deduction, acoustic surface displacement is obtained.

Acta Optica Sinica
Jan. 01, 1900, Vol. 2 Issue 4 367 (1982)
Extraction of directional construction from photograph by optical filtering
LU XIAOJING, and ZHAO SHUQING

The directional characteristic of some objects is analysed by means of 2D Fourier series. The Fourier coefficients have been numerically calculated for the typical objects, and by using optical filtering the objects are extracted from pictures. Then, optical directional filtering for the satellite-photograph is performed. Experimental results are given.

Acta Optica Sinica
Jan. 01, 1900, Vol. 2 Issue 4 360 (1982)
Inquiry about the design of rotating mirror house of the streak camera
XU JIALONG

The design of mirror house at home and abroad has been reviewed simply in this paper. A new consideration for design of the house is proposed, analysis of the chief characters and application vista are given. According to the optical principle of the streak camera, the coordinate equations of the image point have been derived before and after the plate glass is added. Since the plate glass is added, the writing rate of the image on the film track is given. The calculation indicates: the larger relative aperture of the instrument, the thiner plate glass is allowed, the rigorouser the requirement of axial displacement. When mirror rotates, the J-curve of the axial image points for different relative aperture is shown. Proceed from actual instrument, the performances of the instrument using a spherical corver or plate glass are compared. The defocusing dS' is a critical data for streat camera, it will directly affect the imageing quality of the instrument.

Acta Optica Sinica
Jan. 01, 1900, Vol. 2 Issue 4 355 (1982)
A holographic diagnosis of Iaser beam
YU WENYAN, and WANG GUIYING

This paper reports a holographic interference method for measuring wavefront of laser beam. A telescopy is placed in an arm of ring interferometer, so an expanded laser beam and a reduced laser beam are produced. These two beams should interfere and form a co-axial hologram. The curvature radius of the laser beam is obtained by measuring localization of the reconstructed image. The measurement precision of the wavefront curvature radius corresponds to the depth of focus, three time higher than common interferometer. And the pattern is direct visual and spatial resolvable.

Acta Optica Sinica
Jan. 01, 1900, Vol. 2 Issue 4 349 (1982)
Optical properties of ion-implanted Si by CO2 intense-laser annealing
LI YUANHENG, and LI YUANHENG

We have experimentally investigated variations in ellipsometrical parameters ψ, Δ, ρ, reflectivity R,surface sheet resistance p with radiation time by GW OOa laser annealing. Output power of 002 laser is 40 watts and beam diameter <~8 mm. 150 keY As+ ions were implanted to a dose of 1×10 16/cm2 for 6~8 Ω*cm(100)P type Si. The experiments discovered that t|r, A, R, 0 didn't obviously change in initial stage, but sharp decreased to the vicinity of values of the crystal silicon at 5 seconds radiation, and there were no any changes when extending radiation time. Measurements of thermoelectric couple and optical pyrometer shown surface temperature of Si has already reached about 1000 K in condition of 5 seconds radiation. The ifj, Zl-radiation time relation is similar to \ft, Zlof curves, it explains that OW OOa laser annealing has the characteristic of thermal annealing. We can understand from an abrupt turn in A, R, p curves that laser annealing of ion-implanted layer is swiftly completed during 1~2 seconds, and is not any linear or gradual process.

Acta Optica Sinica
Jan. 01, 1900, Vol. 2 Issue 3 285 (1982)
The self-off effect in the shearing interferometer with a single plate
WO MINZHEN, LU DENGWU, LI QINXIONG, and WANG NENGHE

In the shearing interferometer with a single plate, the wedge of the plate is regarded in general as one of the sources of the measure errors. A new effect in the shearing interferometer with a single plate-the self-set off effect is described in this paper. Thus, the wedge of a plate isn t not only the error sources in measuring the wave front, but also at the same time obtains the radius of curvature of the wave front together with the wedge of the plate from the readings of the interference fringes counted in two different conditins.

Acta Optica Sinica
Jan. 01, 1900, Vol. 2 Issue 3 280 (1982)
Tunable nanosecond pulse train generation using gain saturation and frequency locking effect
TANG XINGLI, and PAN ANPEI

A new method is presented for producing tunable ns duration pulse train from a fiashlamp pumped dye laser using gain saturation and frequency locking effect. This method employs two coupled cavities. A tunable seeded pulse, which is produced in a short cavity contained tuning elements, is injected into another long cavity without tuning elements. Then the pulse modulation is formed and continued relying on gain saturation. The spectrum of the output pulses is locking at the frequency of the seeded pulse relying on the frequenoy locking effect. This method gives a higher tuning efficiency. The number of the output pulses can be controlled without pulse selective arrangements, with the Rh6G in ethyl alchol the pulse trains of 3 ns duration pulses with less than 0.01 nm spectral width were obtained.

Acta Optica Sinica
Jan. 01, 1900, Vol. 2 Issue 3 275 (1982)
Axial effects of pressure difference on He-Cd laser
ZENG YONGJIAN, and QIU MINGXIN

It is found that there exists a notable axial pressure difference of 1 to 2 torr during the operation of the He-Cd laser, which is about a half of the He operation pressure or 3 times of the pressure difference in pure He electric discharge. The effects of pressure difference on laser output, noise and stability are investigated. After using a diffusion return path, the laser output power at 4416 A. is increased from 80mW to 110 ml, the noise is decreased to 1.3% at 44161 and to 0.9% at 3250A, and the stability of laser output is greatly improved. The rate of Langmuir flow moving along the direction from the cathode to the anode is calculated to be I5cm3/sec. The experiment results are discussed. The decrease of pressure difference may reduce the sputtering of cathode, and thus prolongs the lifetime of laser.

Acta Optica Sinica
Jan. 01, 1900, Vol. 2 Issue 3 270 (1982)
On Langdsberg s (лaHAcoepr) dielectric constant ellipsoid
GONG YISEN

Academician of the Soviet Union Langdsberg (Jlaimcoepr) introduced a dielectric constant ellipsoid in this book "Optics". He condsidered that the total values of the dieleotric oonstants in crystals can be represented by a dielectric constant ellipsoid. The three semi-axes of this ellipsoid are respectively of lengths &1} ea, e3, i. e. the principle oomponents of the dieleotric constant tensor, and the length of any radius veotor of this ellipsoid is equal to the dielectric constant in that direction. In other words, Langd-sberg's dielectric constant ellipsoid corresponds to the dielectric constant tensor. It is pointed out in this paper that the dieleotric constant tensor corresponds to Fresnel's ellipsoid rather than Langdsberg <3 dielectric constant ellipsoid. This correspondence relation is unique. Dielectric constant tensor is a symmetrical second rank tensor, its six independent components are just equal to the six coefficients of Fresnel's ellipsoid equation respectively. Mathmatical derivation indicates that the length of any radius vector of Langdsberg's ellipsoid in not equal to the dielectric constant in that direction. Conversely, the surface whose length of radius vector in a given direotion is equal to the dielectric constant in that direction, is an ovaloid of six degrees. Besides, in this paper, confusing terms, such as dielectric constant ellipsoid, dielectric ellipsoid Fresnel's ellipsoid and index ellipsoid, and their respective corresponding tensors are clearly defined.

Acta Optica Sinica
Jan. 01, 1900, Vol. 2 Issue 2 188 (1982)
The measurement of time-synchronization for six-beam laser by making use two-photon fluorescence
Yu WENYAN, XIE ZIMING, LI ANMING, and HE XINGFA

In. the target experiment by multi-beam irradiation time-synchronization is very important. Using a method of two-photon fluorescence (TPF), we have measured the time-synchronization of six beams Nd3+ glass high power laser system (6 X 1011 W). The active-passive mode-locked Nd3+: YAG oscillator of the time-synchronization was used as the light source for the time-synohronization measurement. The pulse width was 20 ps. Time-synohronization for two opposite beams was measured using a TPF cell capable of four beam transmission on the position of target. Time-synohronization for two crossed beams was measured by placing a half-transparent film on the target position and a TPF apparatus. The measurement is simple and perceivable. The error in the measurement of the time-synohronization by two-photon fluorescenoe is presented. The error is about 4ps for two opposite beams and 5ps for two crossed beams. The total error of the time-synchronization for six beams is about 10 ps.

Acta Optica Sinica
Jan. 01, 1900, Vol. 2 Issue 2 182 (1982)
A method to determine refractive index profiles for graded optical waveguides
LI QU, CHEN YINGLI, and FANG JUNXIN

A method of optimization using statistical tests has been used to investigate the refractive index profiles for graded optical waveguides. A rational merit function and a practical computation procedure have been developed. Calculation was done to determine the index profiles of Ti in-diffused LiNbO3 waveguides produced in our laboratory. Comparisons with the methods reported so far reveal some advantage of our method.

Acta Optica Sinica
Jan. 01, 1900, Vol. 2 Issue 2 177 (1982)
The ultraviolet stimulated Raman scattering in optical fiber
YANG TIANLONG, GAO PEIJUAN, and STU HAIZHENG

Using the third harmonic radiation of a YAG: Nd laser Radiation as excited light, we have observed the ultraviolet stimulated Raman scattering in optical fiber. The peak-wavelengths of stimulated Raman scattering were identified which distributed at 361.0, 372.2 and 379.1 nm. The corresponding scattering elements of separate peak of stimulated Raman scattering spectrum were analysised.

Acta Optica Sinica
Jan. 01, 1900, Vol. 2 Issue 2 174 (1982)
Analogous processing of the photogram by using the facsimile
WANG NENGHE, Wo MINGZHEN, Lu DENGWU, and ZHANG WEIXING

A method for density slicing of a photogram and iso-density maping by using the BC002 facsimiler is described. It has the advantages of high-processing rate simple device and acceptable pricision. The reformed equipment is valuable in practical use.

Acta Optica Sinica
Jan. 01, 1900, Vol. 2 Issue 2 171 (1982)
Discharge analysis in the mixture of rare gas and molecule including halogen
FU SHUFEN, and CHEN JIANWEN

In this paper, the conditions for the initiation of a high-pressure uniform glow discharge was analysed, and the minimal preionized initial electron density and the optimum seed gas fraction was given. For the usual experimental conditions for a discharge excited XeF laser, the charged particle density under the steady-state discharge has been calculated. Following these obtained values, we have also discussed the difficulties in continuous operation.

Acta Optica Sinica
Jan. 01, 1900, Vol. 2 Issue 1 92 (1982)
A Brewster-Prism Beam Expander
Xu ZUYAN, and DENG DAOQUN

A new type of beam expander suitable for pulsed dye lasers is described. The system is small in volume and has a large expansion ratio, low loss and a high degree of polarization. Calculations for the design and experimental results are given.

Acta Optica Sinica
Jan. 01, 1900, Vol. 1 Issue 6 575 (1981)
Spectrum distribution of sea waves analysed using optical Fourier transforms from seasat SAR images
ZHANG FENGLIN

This paper presents optical Fourier transforms having been used to measure wavelengths and orientation of sea waves in the Jasin area of the North Sea, that is located approximately 200 km north-west of Scotland. Input films were obtained from a synthetic aperture radar (SAR) borne on a satellite. The research work was carried out in Blackett Laboratory, Imperial College of Science and Technology, using optical Fourier transform equipment. The Institute of Ooeanographio Science provided us with SAR films as well as a grant partly. Comparing the results obtained from direct measurement on the sea, or using the computer to calculate optical Fourier transforms of the input films of sea waves, with that obtained from our method, it is obvious that this method is quicker and more reliable. Under the guidance of Prof. W. T. "Welford, the researoh work was completed by Canadian academic visitor, Dr. R. A. Lessard and the author jointly. I would be grateful to those who might point out any error which I made in this paper.

Acta Optica Sinica
Jan. 01, 1900, Vol. 1 Issue 6 569 (1981)
Fast-response surface electrode pyroelectric detector
FENG XIQI, and PAN JINCAI

A new type fast-response detector is recommended. This pyroeleotrio detector is made of LiTaO3 and LiNbO3 crystals, having very strong absorptive characteristics for laser at certain wavelength. In this paper, the consideration in device design, the selection of materials, the fabrication and performance of such device are described and finally, its prospect for the monolithic pyroelectrio array is briefly dissoused.

Acta Optica Sinica
Jan. 01, 1900, Vol. 1 Issue 6 563 (1981)
Highly stabilized laser giant pulse output using superradiance as trigger signal of the Q-switch
[in Chinese], [in Chinese], [in Chinese], and [in Chinese]

The optically regenerative Q-switch method, by which the laser output can be stabilized, is simple and easy to operate. But the disadvantages of laser prepulses inevitable and the successive pulses easily produced severely limit the applications of this method to laser amplifiers and laser range-finders. To overcome these shortcomings we have designed a new method using axial superradiant signal to trigger the Q-switoh. The principle is as follows: The superradiant signal intensities near the axial correspond to certain population during the laser process of the optical pumping. So we can oontrol the population whioh can trigger the Q-switch by controlling the superradiant convert electrioal level in the superradiant deteotor and then the laser output can be stabilized. ISfear the laser threshold the variation of peak heights of laser pulses controlled by ■superradiant signal triggered Q-switch is reduce^ to only 1/4 of original value when we change the voltage of xenon-flash lamp near the laser threshold. The laser output reproducibility may also be improved by this method.

Acta Optica Sinica
Jan. 01, 1900, Vol. 1 Issue 6 559 (1981)
Measurement of energy distribution on focal plane of an imperfect processed optical system
DENG XIMING, and ZHAO QINCHUN

This paper describes a method of "optical tracing" used to measure the energy distribution on focal plane of an imperfect processed optical system. It is similar to Hartmann method. High brightness He-Ne laser with TEM00 mode output is used as a probing beam. A parallel beam passes through a movable aperture and is focused by a local part of optical system to be measured. Then we determine the position of central point of Airy spot on the focal plane. The spatial coordinate of the point is magnified to 40X by an objective and read out by microscope. Coordinate of each central point of Airy spot corresponding to each local part is obtained if the aperture can be moved in the whole optical system. In the case that the optical system is divided into m parts by the movable aperture, there will be m points on focal plane. The ratio of the point numbers on a local part of the focal plane to to is proportional to the relative energy of incident beam focused on it. The accuracy of this method can be up to the magnitude of Airy spot diameter of the whole optical system. The movable aperture is defined as 1/10 of that of the optical system, since the accuracy determining central point of Airy spot of the movable aperture can be up to 1/10 of the spot diameter. The focal spot size and energy distribution on focal plane of aspherical-gpherical lenses for laser-plasma interaction research have been measured using this mathod. It provides basis for improving lens processing and calculating the energy density on target plane.

Acta Optica Sinica
Jan. 01, 1900, Vol. 1 Issue 6 553 (1981)
Pulsed mode and differential mode zero-setting gratings
ZHU JIBIN, and HU XIN

The description of existing pulsed mode zero-setting gratings in connection with their imperfection in the theory relevant to the locating accuracy is given. And at the same time, a new type of zero-setting gratings, namely, of the differential mode zero-setting gratings is suggested in this paper.

Acta Optica Sinica
Jan. 01, 1900, Vol. 1 Issue 5 475 (1981)
Memory limit of point holographic images
SONG WEIGUANG, CHENG ZHONGREN, and LI GE

It is expected that, on the Fourier-transform plane of objective lens, the point holographic image formed by object beam and reference beam is capable of higher memory density of Chinese characters and other foreign letters. Therefore, the memory limit which is related to the relative aperture F of the objective lens, the wavelength of the illustrating light and the number of terms of frequency and spectrum in the image are discussed. And all of these have been identified by our experiments.

Acta Optica Sinica
Jan. 01, 1900, Vol. 1 Issue 5 469 (1981)
The experiments of word-translation with Fourier hologram
LING DEHONG, ZHANG CHENGHUA, and WANG CE

A Fourier hologram with informations in the reference beam can be used as a holographic translator. The analysis is made based on the reciprocity of object beam with reference beam and experimental results are presented in this paper. The effect has been improved through the spatial amplitude modulation.

Acta Optica Sinica
Jan. 01, 1900, Vol. 1 Issue 5 463 (1981)
Model JQY-300 laser holographic interferometer
WANG WENGUI

The model JQY -800 la3er holographic interferometer is an instrument used for uniformity measurement of large size optical glass by means of double-exposure holographic differential interferometry. The measurement accuracy of ±5xl0~7 can be obtained. The characteristics of structure design are as follows: 1. Foamed rubber is used as vibration-proof leading to a simple construction, Hz vibration can be isolated. 2. The optical path difference introduced by work-table deformation under heavy sample is eliminated, using the method of placing the sample holder at the support point. 3. The sample mount consists of three-dimension angle micro-adjust structure instead of common used ''point, line, plane" positioning structure. It is convenient for machining, assembly, and the requirement of accuracy can be met.

Acta Optica Sinica
Jan. 01, 1900, Vol. 1 Issue 5 457 (1981)
A transient acousto-optically mode-locked Nd:YAG laser
LI SHIYING, CHEN SHAOHK, and XIE ZIMING

An acousto-optically mode-locked Nd:YAG laser, prelasered with an electro-optic Q-switch, energy storage amplified, and modulated with an acousto-optic modulator operated at 50 MHz is described. In the case of embedding a dye-cell into the cavity, the mode-locked laser can be operated either actively or passively. The performance of this laser is as follows: the pulse width varying continuously from 20 ps to several ns, energy of a single pulse greater than 0.1 mJ, and the amplitude stability of the pulse train better than 90%.

Acta Optica Sinica
Jan. 01, 1900, Vol. 1 Issue 5 451 (1981)
Study of performance for discharge excited N+2 laser
CHEN JIANWEN, FU SHUFEN, and LIU MIAOHONG

The experimental results for N2+ laser are presented. The measured optimum partial pressure of N2+ was 2.4 torr at a total pressure of 2 atm. in He/N2 mixture. Kinetics of formation and quenching are analysed and discussed. The spectra of the N2+ laser at 427.8 nm were determined with the second order spectra of a 2-meter grating spectrometer. We observed that the 427.8 nm line is a doublet.

Acta Optica Sinica
Jan. 01, 1900, Vol. 1 Issue 5 445 (1981)
Tunable synchronously pumped ultrashort pulsed double-beam lasers
CUI JUNWEN, LI QUN, HUI LINGKAI, and LIU SONGHAO

This paper reports the experimental results about the ultrashort pulses from two tunable dye lasers, which are synchronously pumped by the second harmonic of an active-passive mode-locked Nd: phosphate glass laser.

Acta Optica Sinica
Jan. 01, 1900, Vol. 1 Issue 5 441 (1981)
Nonlinear index in the gain medium
FAN DIANYTTAN

The nonlinear index of refraction induced by stimulated transition of high level populations in the gain medium is investigated. Taking example of active Nd:glass, we have specifically calculated the law of index changing with laser intensity. Several physical effects related with this nonlinearity, as self-defocusing, self-modulation, nonlinear aberration, pulse distortion etc. are indicated.

Acta Optica Sinica
Jan. 01, 1900, Vol. 1 Issue 4 379 (1981)
Dynamic Fabry - Perot interference effect of parallel plane Ge by intense laser
LI YUANHENG

Experiments show that transmittance of parallel-plane Ge changes quasi-periodically with time under CW CO2 laser radiation. Basing on multi-beam interference theory for parallel-plane and considering influence of laser-induced temperature change on refractivity and thick of Ge, calculated result is consistent with experimental data. It indicated that parallel-plane Ge has a dynamic Fabry-Perot interference effect as dependences of refractivity and thick on temperature by high power CW CO2 laser heating.

Acta Optica Sinica
Jan. 01, 1900, Vol. 1 Issue 4 377 (1981)
An approach to the method of vignetting determination
SHA CUNXIAO

In this article a specific lens is taken as example to approach the method of the determination of pupil shape, to stress under certain circumstances the existence of surplus inflection points and its cause using the prevalent cubic interpolating splins recently, and finally to put forward two schemes subjected to tests for reference.

Acta Optica Sinica
Jan. 01, 1900, Vol. 1 Issue 4 371 (1981)
A collinear CS2 picosecond optical gating
CHEN SHUGIEN, ZHAO JIRAN, and GAO FUYAN

A collinear arrangement of optical shutter with ultrahigh time-resolution is introduced. An ultrashort pulse of Nd:glass laser is used as an ignition pulse and CS2 liquid as Kerr medium. Correlation time of 15 picoseconds has been measured. We obtain that the full width of half maxium of 1.06μ ignition pulse and 5300A signal pulse are 12 picoseconds and 8 picoseconds respectively.

Acta Optica Sinica
Jan. 01, 1900, Vol. 1 Issue 4 365 (1981)
Emissivities of cylindrical cavities with reverse conical bases
XIB SHUNKANG

The local effective emissivities of diffuse isothermal cylindrical cavities with reverse conical bases are precisely calculated, and it is indicated that the optimum value of the eone length situates between three and four tenth of the cylinder length.

Acta Optica Sinica
Jan. 01, 1900, Vol. 1 Issue 3 285 (1981)
Radiant performance studies of discharge excited XeF lasers
FU SHUFEN, CHEN JIANWEN, and LIU MIAOHONG

This paper reports the dependence of the radiant performance of a UV-preionized XeF laser on the varied parameters. The output energy of 250 mj was obtained with a miiture gas pressure of 2.5 atm., using Ne as the buffer. Base on the calculation of Boltzmann s transfer eqution, discharge transfer processes in He-Xe and Ne-Xe mixture were discussed.

Acta Optica Sinica
Jan. 01, 1900, Vol. 1 Issue 3 281 (1981)
A resonant cavity suitable for TEA CO2 laser
Lou QIHUNO

A optical resonant cavity with square coupling output hole suitable for TEA CO2 laser is designed. The intensity profile of this cavity is rather uniform and the beam divergence is four times better than concave-plane cavity.

Acta Optica Sinica
Jan. 01, 1900, Vol. 1 Issue 2 189 (1981)
On the target resolution of line scanners
ZHANG XIAOLIN

The target resolution of line scanners is analyzed quantitatively. It is concluded that its resolution greatly exceeds the limit of instantaneous field of view (IFOV). When the scale of the target or its internal radiance distribution is smaller than the IFOV, we can abtain a distorted, i.e., expanded and boundary blurred response. But if the contrast of target radiance distribution is large enough, this distribution can be imaged and distingushed. Particularly, for linear or spot targets, as long as the contrast or radiance increases by a factor of Sl/St, it can certainly meet the condition of any equations constructed for the distinguishable targets, here SL and ST expresses respectively the areua of the IFOV and the target. If we further make use of the difference of spectral characteristics between the target and background, we can improve the target resolution obviously.

Acta Optica Sinica
Jan. 01, 1900, Vol. 1 Issue 2 181 (1981)
Investigation of filtering materials suitable to lasers using transient absorption in Nd:YAG crystals
YE BIQING, ZHA GUIGEN, and MA ZHONGLIN

The obvious transient absorption at the laser wavelength in Nd:YAG laser crystals is attributed to the production of transient colour centres, induced by UV light irradia-tion. The filtering characteristics of the materials are investigated by means of this phenomenon. The filtering materials suitable to lasers are selected effectively using the combined Nd: YAG cw laser system. In addition, we obtained the relation between pumping powers of different rods at the threshold in the combined laser. As compared with Mori's, our formula is a quantitative expression containing a variety of coefficients.

Acta Optica Sinica
Jan. 01, 1900, Vol. 1 Issue 2 175 (1981)
The waveguide electro-optic prism
LI YUSHAN

The guided-wave electro-optic prism has been fabricated by the process of photolithography on a Ti-diffused LiNbO3 waveguide. When it is used as an intensity modulator, the driving voltage is ±19V for 100% modulation depth, the fundmental bandwidth is 1.5GHz,and the driving power per unit bandwidth is 9.5mw/MHz. When it is used as a bipolar switch, the switching voltage is ±19V, and the switching time is 0.1ns.

Acta Optica Sinica
Jan. 01, 1900, Vol. 1 Issue 1 93 (1981)
A Fourier transform doublet lens
WANG MINQIANG

A Fourier transform lens of the doublet type with small air separation is described. The anomalous combination of glasses is used to reduce the Petzval sum, while a proper amount of spherical aberration and coma is held to control the astigmatism. The image quality is diffraction limited in both input and frequency planes at f/10.

Acta Optica Sinica
Jan. 01, 1900, Vol. 1 Issue 1 89 (1981)
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