A new two frequency laser alignment system is developed which consists of two Wollaston prisms with the same structure. One is for measurement; another for compensation. Using phasemeter, the two prisms can be moved out off the beam, so the system can be used to measure coaxality. The displacement drift and angle drift of laser beam are compensated by the optical system automatically. The paper analyzes those adaptive characteristic in theory. Experimental result is in concordance with theoretical analysis.

In this paper, based on the increment algorithm, the clipping learning method and Monto Carlo algorithm were used in optimization of a cascaded neural network. As a result, binary interconnection weights were obtained. The error tolerance of the neural network was tested by non learning sets. Computer simulation indicated that the results were satisfactory.

The optical interconnections in photorefractive crystals is studied and a method is proposed to perform optical switch, broadcasting interconnection, combining interconnection, and point to point interconnection at the same configuration by using bridge phase conjugator′s configuration. The intensity and temporal properties of the optical interconnection are discussed under the configuration of photorefractive two beam coupling.

A novel optical whole field profilometry is presented. A new kind of moire fringe projector controlled by computer is used for changing the spacial frequency to adapt the contour of the object to be measured. Besides, a method named “Two Times Measurement with Different Precisions” is proposed in order to measure an object with sudden surface changes. The satisfactory results are obtained.

We have modified the calculation model of the probe fields of the photon scanning tunneling microscopy (PSTM), and derived more practical calculation formula of the probe fields and transmission coefficient of PSTM . Using these calculation formula, we carried out the numerical imitate calculation on the computer and obtained some new results.

We report the emittance measurement of a electron beam produced in a pseudospark discharge device driven by a pulse line accelerator. A ten gap pseudospark device was operated at 200 kV, with anitrogen gas fill presure of 15 Pa. Small diameter (～1 mm) electron beam with current about 2 kA has been generated. The rms emittance of the beam is measured to be ε rms ≈ 48 mm·mrad about 5 cm downstream of the anode plane. The normalized emittance is then found to be ε n≈ 47 mm·mrad.

Based on rate equations of carriers and photons, using transfering matrix method method, the gain saturation properties of semicoductor laser amplifier (SLA) are analysed theoretically. The dependences of SLA′s gain and gain saturation on the injected current density and facet reflectivity are discussed. Although the Auger process may increase saturation intensity, it decreases the internal quantum efficiency and unsaturated signal gain greatly, so it isn′t desired in SLA.

An approximate analytical method is presented for the use of analyzing metal clad dielectric waveguides near cutoff. The mode propagation and photo electric modulation characteristics near cutoff are discussed in detail. And, the cutoff condition of rib waveguide cutoff modulator is analysed by using the simple effective index method.

In this paper the effect of parasitic oscillation on the gain of main amplifier in “SHANGUAN Ⅱ” facility are discussed. The experimental and theoretical calculation results are given.

The efficient lasing output from 2 (2′ hydroxyphenyl)benzoxazole(HBO) in cyclohaxane, based on excited state intramolecular proton transfer (ESIPT), is reported. The laser energy conversion efficiency is measured to be about 17%. And the tuning range is 495 nm￣540 nm. By considering the mechanism of ESIPT, we develop a kinetic model of proton transfer laser for HBO to calculate numerically the spectra and instantaneous features of the broad band and narrow band emissions. The calculated results are in agreement with the experiment very well. In addition, the calculated results show that the pulse duration of proton-transfer laser dependents on the ground-state lifetime of keto-tautomer of ESIPT molecule.

A beam homogenizer was used to improve the intensity distribution of the output beam from XeCl excimer laser. The results demonstrated that the irradiation uniformity was better than 2%. Using this apparatus, the etch threshold of solid thin film was measured and excimer laser induced electrical conductivity in C 60 thin film has been studied experimentally.

A narrow band diode laser with novel structure of external cavity is reported in this paper. With weak optical feedback, the laser linewidth was narrowed to below 500 kHz. This diode laser can be used for the study of high resolution spectroscopy, magnetic optical trap and atomic fountain frequency standards etc. In addition, we studied theoretically and experimentally the relation between linewidth and current tuning rate in detail. The obtained formula was proved by means of saturated spectroscopy.

Laser diode direct coupling pumped Nd∶YVO 4/KTP intracavity frequency doubling laser was demonstrated by closing the Nd∶YVO 4 crystal to the emitting area of laser diode. Green laser of TEM00 mode at 532 nm with a maximum output of 73 mW and a optical to optical efficiency of 14.5% were obtained, when pump power was 503 mW.

High efficient intracavity frequency doubled Nd∶YVO 4/KTP laser pumped by a laser diode was reported. The dependence of output power and efficiency on the size of pump spot, cavity length, temperature of KTP and Nd∶YVO 4 was investigated. The output power of 154 mW at 532 nm and optical to optical conversion efficiency of 23% were obtained at the incident pump power of 669 mW.

Nd∶S-FAP is a low threshold and high efficiency laser crystal. The characteristics of diode laser end pumped lasing of Nd∶S-FAP are studied. The single transversal TEM00 has been obtained. The pumping threshold is 9 mW and the slope efficincy is 37.3%.

The interrelations between the parameters of VRM and Cassegrain unstable resonator and their effects on laser intensity distributions are studied in this paper. The experimental results of Nd∶YAG laser using VRM output coupler are presented in detail. Up to 1.4 J TEM 00 mode output pulse (10 ns, 10 pps) with 1.1 diffraction limited divergence can be obtained by using VRM unstable resonator and one amplifier. The effeciency of SHG is 60% and THG is 30%.

In this article, the behaviors of the suppression of spectral narrowing, gain saturation and reduction of amplified spontaneous emission (ASE) are analysed in the case of a grating pair which is used to introduce spatial dispersion in the ultrashort pulse amplifier. The gain factor greater than 10 3 was obtained experimentally with a 4 f system single stage dye amplifier.

The new type of microchannel cooling laser diode arrays are used as the pump source of Nd∶YAG oscilator and Nd∶YAG slab multipass amplifier, in which the SBS phase conjugation mirror of CCl 4 is used to improve the beam quality. At the repetition frequency of 750 Hz the laser beam with the pulse width of 15 ns and average power of 180 W is obtained. The beam divergence of system is measured to be 1.5× the diffraction limit.

The lattice vibrational spectra and d d electron transition spectra of the Cu∶KNSBN are compared with that of the KNSBN. The differences in the Raman spectra are little for the symmetry species A 1(z) and are very great for the symmetry species E(xy); but in the infrared reflectivity spectra, the differences are great for both A 1(z) and E(xy). It is considered that the lattice sites A and C are partly occupied by the Cu 2+ doped. The d d electron transition spectra in the visible range show that the two deep energy levels of 2.50 eV and 2.64 eV are formed by the Cu2+.

The stability of stimulated Brillouin scattering (SBS) conversion efficiency and phase conjugation (PC) fidelity are mainly depend on the leading edge of pump pulse. If the rise time of the leading edge of the pump pulse is near to the acoustic phonon lifetime of SBS medium and pump energy is well over the SBS threshold, the SBS PC fidelity will become very unstable. For pump pulse with 2 ns leading edge and CCl 4 medium with about 1 ns acoustic phonon lifetime, when introduced a small slow rising signal at the front foot of the pump pulse's leading edge, a stable SBS produced by two-cell SBS PC mirror is obtained even for pump pulse energy exceeding 500 times SBS threshold. The fluctuation of the SBS conversion efficiency is within 4%, and that of the PC fidelity is within 5%.

A new optical bistability is predicted, in which the bias voltage is refered as input and the light intensity in the centre of far field facula of Gauss light beam passing through Bi 12 SiO 20 (BSO) crystal as output. This bistability has been demonstrated in the experiment of positive bias voltage and negative bias voltage conditions. The experimental results are in consistent with the theory.

Using the compact matrix forms of third order susceptibility, we have derived the expressions of effective third order nonlinear coefficients for third harmonic generation (THG) processes in uniaxial crystals. These expressions are significant in finding the optimum incident directions for THG in uniaxial crystals.

A theory of the excitation of ultrasound waves arised from photoelastic coupling with high intensity light is presented in this paper.By use of several reasonable approximations, a numerical calculation of the transient stimulated Brillouin scattering (SBS) process shows that a large amplitude of acoustic wave can be built up during the pulse of pump light, and which may result in damage to optical materials.

In the W flat with Weigert effect, both dichroism and birefraction should be showed simultaneously, but the birefraction is neglected generally because of it′s small. In this paper, we give a experimental result showing a remarkable birefraction as the dichroism is very strong (the phase difference between extraordinary and ordinary light be able to 80° and the value of n e-n o～0.02). A series of data and curves of the experiment are obtained. A principle and experimental method for determining the dichroism and the birefraction of a W flat are suggestees.

By using the Fourier transform method and the Schwarz inequality, the relation M 2>1 is proved, where M 2 is the optical beam quality factor of nonparaxial scalar light beam. And furthermore, some other aspects of the second moments theory are discussed.

A new method named Layer by Layer Analysis Method was presented to analyze the diffraction efficiency of binary optical elements. To four step binary optical elements, the effects of fabrication errors, such as depth and alignment errors, on the diffraction efficiency were investigated in detail. It was shown that this method is very convenient and effective to the analysis of diffraction efficiency of binary optical elements with alignment errors.

Using the fast Fourier transform (FFT) algorithm to make the solution of paraxial wave equations, we develop a x ray laser wave optics code XWAVE based on a model of amplified spontaneous emission(ASE). It includes diffraction, gain saturation, and refractive effects due to electron density gradients. The results of coherence, spatial distribution and angular distributions of x ray laser are presented, which agrees with the results of gain coefficients and angles of divergence in the multi-target experiments.

The spatiotemporal characteristics of the instability induced by counterpropagation has been investigated experimentally in photorefrative crystal. The results from power spectrum and correlation dimension quantitatively confirm the transition to chaos through the periodic three.

The paper provides a new understanding and correcting suggestions towards the traditional abrration theory. The drawback in the transfer surface magnification and abrration coefficient formulas is pointed out.

The asymmetric X junction was applied in the GaAs Mach Zehnder optical switch instead of the traditional Y branch, and a 1× 4 switch array was designed and fabricated. The basic mechanism of the asymmetric X-junction and, then, of the switch array was briefly narrated. The consideration for the designing and fabricating process were presented. The switch unit in this device operating at 1 15 μm has a switching voltage of 12 V and a crosstalk of less than -20 dB. The propagation loss in the waveguide of this device is about 7 dB/cm. The factors causing the crosstalk and the loss in this device were analyzed.

Possible refractive index profiles and other major parameters of the small dispersion single mode fiber (SDSMF) with ±2 ps/km/nm dispersion are presented in this paper, and their applications are discussed. Results show that SDSMF is suitable for high speed, WDM+EDFA systems, both for its non zero dispersion to effectively suppress the four wave mixing (FWM) effect, and small dispersion to avoid severe dispersion induced degradation. When dispersion compensation is employed in the sequence of ITU-T G.652 conventional single-mode fiber (CSMF) and negative SDSMF between two adjacent in-line amplifiers in a 10×10 Gb/s, 10 stage EDFA system, it offers the advantage of not only reducing the required system bandwidth from 16.2 nm to 9.4 nm at tolerable penalties caused by dispersion and FWM, but also making it possible for equal channel-spacing transmission which significantly simplifies system design.

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.

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.

Three dye lasers are used to excited Sr atoms to obtain ions and electrons through autoionization process. The wavelength of the second laser is scanned when those of the first and third lasers are fixed, through which spectra of Sr 5sns 1S 0 and 5snd 1, 3 D 2 series are measured. Experimental spectra are described and analyzed by multichannel quantum defect theory, which verifies measured data and predicts unmeasured data with their energies and wave functions. The study also provides radiative lifetimes of highly-excited states. Agreement between the theory and experiment is achieved. This work also agrees well with previons studies.

Using a VUV monochrometer and a rotating polygon mirror, the time space resolved VUV spectrum is obtained for the first time in the single pulse discharge of Tokamak. The measurement error from the conventional method of shot by shot discharge is avoided.

A method for calibrating spectral bidirectional reflectance in any illumination and viewing geometrics is proposed. The absolute bidirectional reflectance factor of a standard sample made by sintered polyte trafluoroethylene (PTFE) is determined in the range of 400-2500 nm. The reference standard is direction hemisphere reflectance factor transferred by the National Institute of Measurement. The absolute bidirectional reflectance factor can be measured on the instrument of measuring bidirectional reflectance factor can be measured on the instrument of measuring bidirectional reflectance-distribution function at nearly all the illumination and viewing geometrics.

Stark spectroscopy(electroreflection spectroscopy) technique was applied to investigate the exciton transitions and charge transfer excitations in a Tin phthalocyanine(SnPc) polycrystalline film. A series of intermolecular charge transfer(CT) spectral bands was observed, which demonstrated the unique advantage and high sensibility of Stark spectroscopy in revealing weak CT transitions buried under strong Frenkel exciton bands. Photovoltaic action spectrum was measured for an ITO/SnPc/Al sandwiched device. The role that CT excitons played in photoconductivity was discussed.

A double layer organic thin film electroluminescent device (DLD) (ITO/SA/Alq3/Al) and two three layer devices (TLD) (ITO/SA/PBD/Alq3/Al) with different thickness of PBD have been prepared. Here SA is a kind of derivative of styrylphenylamine. The EL spectra, current voltage, brightness voltage and efficiency of the devices have been investigated. It was found that TLD with 35 nm PBD emitting both from Alq3 and SA, and DLD and TLD with 10 nm PBD have higher current density and brightness over 2 orders than TLD with thicker layer PBD, though that the quantum efficiency of three decives are almost the same. The quantum efficiency of devices with SA are 0.09~0.1%, much higher than the single Alq3 layer device (0.04%). Energy band models were schemed to well complain the EL performance of the devices. The stability against air was studied also. After put in air for ten months, the brightness of the devices is about 50% of its initial one.

The preparation method and stalic property of phase change optical storage Ge 2Sb 2Te 5 thin film have been analysed. After measuring its static properties, we found that the Ge 2Sb 2Te 5 film can be written and erased within 100 ns. Through multilayer design, the write/erase cycle numbers can be as high as 10 6, and the reflectivity contrast is above 15%.

The Electrochromism and preparation of WO 3 thin film were introduced. The resistivity, structure, chemical composition, electrochemical characterization and electrochromic properties were investigated. A new method of the lithiation of WO 3 thin film was proposed which was crucial for the preparation of all solid state electrochromic devices.