Acta Optica Sinica
Co-Editors-in-Chief
Qihuang Gong
[in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

In order to analyze multi transverse modes of a complex index waveguide, a numerical method named RPS is proposed. It integrates real index numerical method, perturbation method and shooting method rationally. The method is simple, fast and precise, and it avoids searching the solution in the whole complex plane. Numerical example shows that all mode solution can be obtained precisely for either TE mode or TM mode of a complex index waveguide.

Jan. 01, 1900
  • Vol. 21 Issue 7 800 (2001)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The escape function algorithm is one of the most practical global optimization algorithm for optical design published so far. This type of global optimization consists of many local optimization runs with or without the excape function using the damped least squares method. To make the algorithm more efficient and powerful, two search schemes are proposed to improve the efficiency of the local optimization runs. The first one searches for the best damping factor which effectively determines the optimum direction of the solution vector in the multi dimensional variable space, and the second search is conducted along that direction to find the optimum length of the solution vector. Experiments are also made to determine the optimum default values for the control parameters of the escape function. The algorithm is successfully implemented in the GOLD program, which becomes an optical software package with a practical global optimization feature for the design of complex optical systems.

    Jan. 01, 1900
  • Vol. 21 Issue 7 835 (2001)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    A real time holographic testing method of transparent objects by using the interference pattern formed by the reconstruction of the reference wave and the original reference wave is introduced. The above interference fringe pattern is proved to be similar to the pattern which is formed by the reconstruction of the initial object wave and the wave scattered by the object during observation. The principle of this method and the characteristic function of the contrast of the interference pattern are presented. The phase distortion caused by any optical element in object optical path can be eliminated and the unexpected light emitted by the under testing object itself can be also avoided by using this method.

    Jan. 01, 1900
  • Vol. 21 Issue 7 841 (2001)
  • [in Chinese], and [in Chinese]

    A new method is presented to construct a kind of compactly supported biorthogonal wavelet based on human visual system. The genetic algorithms are used to find a compactly supported biorthogonal wavelet so that the constructed wavelet can approximate the modulation transform function for HVS.The constructed wavelet is applied to image compression coding in the experiments. The experimental results indicate that the quality of construction with the new kind of wavelet is equivalent to 9/7 biorthogonal wavelets in the condition of the same bit rate,but computational load is less. It has a good performance of construction specially for texture image compression coding.

    Jan. 01, 1900
  • Vol. 21 Issue 7 846 (2001)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    A new method for taking X ray image holograms with tens nanometer resolution is proposed. It employs two micro zone plates, one is for imaging and another for producing the reference. The holograms can be recorded in digital form by a charge coupled device (CCD) camera. The device can also be used as an X ray interferometer, called double zone plate X ray interferometer.

    Jan. 01, 1900
  • Vol. 21 Issue 7 850 (2001)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    Based on super-resolution theory, the 3-D confocal surface profilometry and annular pupil filter are combined for analyzing the property of the 3-D profilometry. The results of computer simulation and experiment prove that this method can explore the axial dynamic range and improve transversal resolution of 3-D profilometry at decreasing axial resolution.

    Jan. 01, 1900
  • Vol. 21 Issue 7 853 (2001)
  • [in Chinese], [in Chinese], and [in Chinese]

    Based on the theory proposed by Walls et al, an experimental scheme of quantum non demolition (QND) measurement for intensity difference fluctuations is put forward, which is realized though a nondegenerate optical parametric amplifier. The relations of transference coefficients and the ability for quantum state preparation are deduced on the nonideal condition, and the influences of probe input noise spectrum and measurement efficiency of detection system on the measurement criteria are discussed, respectively. In conclusion, the smaller probe input noise and the larger measurement efficiency, the measurement quality is better and more sensitive to the measurement efficiency.

    Jan. 01, 1900
  • Vol. 21 Issue 7 857 (2001)
  • [in Chinese], and [in Chinese]

    The influence of backscattering and injected signal on the statistical properties of ring lasers is discussed by a full saturation laser theory. The result shows that the backscattering can reduced the fluctuations of the system. For a homogeneously broadened bidirectional ring laser, the injected signal can drive the weak mode from incoherent light to coherent light. However there is no such driving effect in an inhomogeneously broadened ring laser system. Further study shows that the driving effect of the injected signal also depends on the difference of pump parameters Δ α of the two modes.

    Jan. 01, 1900
  • Vol. 21 Issue 7 778 (2001)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The beam quality has been improved efficiently by means of a varied reflectivity mirror (VRM) unstable resonator used in a tunable Ti∶Al 2O 3 laser, and a tunable blue laser from 396 nm~440 nm through second harmonic generation (SHG) by LBO crystal is generated. The highest SHG efficiency of 27.2% and the maximum output energy of 26 mJ have been obtained.

    Jan. 01, 1900
  • Vol. 21 Issue 7 804 (2001)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    According to Raman gain theory, the optimized design of fiber Raman amplifiers is proposed in different aspects, such as gain medium, pump source and pump condition. The calculated results are also given.

    Jan. 01, 1900
  • Vol. 21 Issue 7 808 (2001)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    A mini all solid state system of non classical light generation has been experimentally demonstrated. The quantum correlated twin beams were generated from a semi monolithic nondegenerated optical parametric osaillator including an α cut KTiOPO 4 crystal pumped by an all solid intracavity frequency doubled Nd∶YVO 4/KTP laser (0.53 μm). The noise of the intensity difference between twin beams was reduced to 3.2 dB below the standard quantum limit. The pump threshold is lower than 10 mW.

    Jan. 01, 1900
  • Vol. 21 Issue 7 812 (2001)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    A simple method of physical design for high power pulsed dye laser amplifier is established based on the gain theory of dye laser steady state. A 52.5 W mean power pulsed dye laser amplifier double sides pumped by copper vapor laser (CVL) has been designed by this method and the physical parameters of the amplifier are given.

    Jan. 01, 1900
  • Vol. 21 Issue 7 815 (2001)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    Bu using a regenerative amplifier with folded standing wave resonator, laser diode array (LDA) pumped regenerative amplification of single longitudinal mode laser pulse with high stability is realized. The build up process of single longitudinal mode laser pulse from injection to regenerative amplification is stuided in detail. The total gain of 1.2×10 7 is obtained in the regenerative amplification. The single pass net gain is 1.5, and the dumped energy of single pulse is 1.2 mJ.

    Jan. 01, 1900
  • Vol. 21 Issue 7 820 (2001)
  • [in Chinese], [in Chinese], and [in Chinese]

    Due to the resonant absorption of interference infrared filters at high power density laser radiation, the laser damage properties of such coatings are significantly different from the high reflective coatings and antireflective coatings. In order to understand the damage behavior of this type of coatings, a series of experiments have been done. The damage threshold for several infrared filters composed of multilayer of ZnS/MgF 2 were determined by irradiation from Nd∶YAG laser. The absorption measurements of such coatings have been performed by the surface thermal lensing (STL) technique. The relationship between damage morphology and damage growth has been studied in detail. The empirical data is compared to theoretical predictions. The interesting phenomena are that most of the initial damage occurs not at the surface layers but inside of the multilayer films, where ZnS is sublimed to form many little air bubbles. Using the electric distribution and temperature field distribution theoretical calculating, the explanation is given. It is concluded that the laser damage properties of such infrared filters are in agreement with theoretical prediction.

    Jan. 01, 1900
  • Vol. 21 Issue 7 829 (2001)
  • [in Chinese], [in Chinese], and [in Chinese]

    A design method for using comb like dispersion profiled fiber (CDPF) to achieve pulse compressing is given, and corresponding numerical model is also presented. Based on this model, the effect of nonlinear phase shift on pulse width and waveform from CDPF compressor was studied under the condition of different pulse peak power. The numerical results reveal that the incident pulse peak power and nonlinear phase shift should be satisfy certain conditions, to get the suited CDPF compressor for using in the ultrahigh speed optical time division multiplexing (OTDM) system.

    Jan. 01, 1900
  • Vol. 21 Issue 7 768 (2001)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    Experimental and theoretical study of Cerenkov type second harmonic generation (SHG) with green and blue output in proton exchanged lithium niobate planar waveguide is reported. The dependence of the proton exchanged waveguide parameters on the Cerenkov type SHG efficiency with different fundamental wavelengths is calculated. The waveguide suitable for Cerenkov type SHG with green and blue output is fabricated and high efficiency SHG is observed in the waveguide.

    Jan. 01, 1900
  • Vol. 21 Issue 7 774 (2001)
  • [in Chinese], and [in Chinese]

    The Doppler frequency shift, the main factor restricting the bandwidth of receiver in inter satellite laser link, with orbit equations is calculated. On the base of theoretical and experimental study in transmission and tunable characteristic of Faraday anomalous dispersion optical filter (FADOF), several novel schemes are proposed based on FADOF′s multi peak and tunable characteristic, to meet the acquisition requirements in different orbit positions. Typical bandwidth of filter is 0.01 nm~0.02 nm.

    Jan. 01, 1900
  • Vol. 21 Issue 7 861 (2001)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The surface plasma waves (SPW) Q switch is proposed. The principle of SPW Q switch is described and the characteristic of SPW Q switch is obtained by theoretical and experimental investigation.

    Jan. 01, 1900
  • Vol. 21 Issue 7 866 (2001)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The angular variable mirror (AVM) to be used to control the power balance of beams of “SHENGUANG Ⅱ” system will affect the light beams, including vertical displacement of optical axis, alteration of equivalent length of optical path, additional optical distance, and the curve of wave surface. By the optical matrix, the effects have been analyzed quantitativelly, and point out that equivalent length of optical path is the different concept from optical distance. The application of AVM in practice is discussed.

    Jan. 01, 1900
  • Vol. 21 Issue 7 869 (2001)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    A technique of time domain addressing is introduced to interrogate a four element fiber Bragg grating sensor array. The sensor elements with different fiber delays were illumined with a pulsed broad band source. Demodulation was achieved with an unbalance Michelson scanning interferometer. The single channel output sensor system, which is with a sensing resolution of 6 nε, was demonstrated with a sensitivity of 1.63°/με.

    Jan. 01, 1900
  • Vol. 21 Issue 7 874 (2001)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    A 1×16 multimode interference (MMI) optical power splitter which allows for connecting with the standard single mode fiber arrays for optical communication directly is designed and fabricated. The input and output single mode waveguides are optimized by the discrete spectral index method (DSIM). Single mode rib waveguide with low theoretical propagation loss (~0.028 dB) and with rib width of 3 μm and rib height of 2.9 μm is obtained. Analysis shows that the deep etched MMI optical power splitter has large fabrication tolerance, big bandwidth and insensitive polarization. The measurement results show that the function of 1 to 16 uniform splitting has been realized in the device.

    Jan. 01, 1900
  • Vol. 21 Issue 7 878 (2001)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    Two types of blue organic light emitting diodes with different structure have been fabricated. The maximum brightness and luminous efficiency for two devices are 3700 cd/m 2, 6123 cd/m 2 and 0 78 lm/W, 0.83 m/W respectively. It is demonstrated that a blocking layer can effectively ragulate the recombination area and obtain the desired light emission. However, the lifetime of the two devices are quite different. Luminance and durability characteristics of those devices are well explained and compared based on energy levels diagrams.

    Jan. 01, 1900
  • Vol. 21 Issue 7 882 (2001)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The influences of super Gaussian control pulse on dynamic gain response of the semiconductor optical amplifier (SOA) and switching characteristics of a terahertz optical asymmetric demultiplexer (TOAD) are studied in detail by considering the effects of gain saturation and recovery of SOA. The results are compared with the case of a Gaussian control pulse. It is shown that the super Gaussian control pulse will decrease the gain transition region of SOA and affect significantly the shape of the switching window of TOAD. When the time delay between the signal and control pulse is fixed, or the loop′s time asymmetry and the time delay between the signal and control pulse are all fixed, the maximum switching contrast of TOAD will be reduced due to the using of a super Gaussian control pulse.

    Jan. 01, 1900
  • Vol. 21 Issue 7 886 (2001)
  • [in Chinese], [in Chinese], and [in Chinese]

    A series of measurments of the irradiance scintillation of a He Ne laser beam propagating over complex terrain were carried out. The statistical properties of the irradiance scintillation, such as the scintillation index, probabitity distribution, and power spectrum were analysed. It was found that these statistical properties of the irradiance scintillation over complex terrain greatly deviate from the theoretic results.

    Jan. 01, 1900
  • Vol. 21 Issue 7 783 (2001)
  • [in Chinese], [in Chinese], and [in Chinese]

    The predistortion linearization technique is usually used to suppress the composite triple beat distortion (CTB) in optical fiber amplitude modulated cable television (AM CATV) externally modulated transmitters. The influence of the incident polarization state with TE mode and TM mode on the CTB performance in optical fiber AM CATV externally modulated transmitters is analyzed with calculation and experiment. The theoretical analysis and calculation have shown that the TE mode is the best mode for performance of CTB suppression. The influence of the incident polarization state drifting off TE mode is also analyzed and measured, and it is shown that the deviation angle from the TE mode should be less than 15 degree so as to the performance for CTB suppression will not be degraded.

    Jan. 01, 1900
  • Vol. 21 Issue 7 787 (2001)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    A principle study of detecting laser frequency signals based on edge technology for atmospheric laser communications is presented. An experimental system is built up in which an iodine cell is used as the edge filter. The experimental results were analyzed in detail. Applying edge technology the communication system has two main advantages, the narrow optical bandwidth and the high stability of laser frequency. So an ultra narrow optical filter with bandwidth about 400MHz can be used in the receiver. The receiver is only sensitive to the frequencies of the laser signals. Most of the interference of background light field can be eliminated. Some problems exposed in the experiments are discussed.

    Jan. 01, 1900
  • Vol. 21 Issue 7 792 (2001)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    Image formation in turbid medium under a microscope is studied using Monte Carlo technique. The relationship of image resolution with absorption property of turbid medium is discussed. The results show that the enhancement of absorption increases the image resolution, and more absorption contributes lower image intensity. It is concluded that the absorption in turbid medium is an intrinsic gating mechanism to refuse the scattered light.

    Jan. 01, 1900
  • Vol. 21 Issue 7 796 (2001)
  • [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.

    Jan. 01, 1900
  • Vol. 21 Issue 7 891 (2001)
  • [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.

    Jan. 01, 1900
  • Vol. 21 Issue 7 894 (2001)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    A recently developed Transient spectrum measurement instrument is introduced. Quantum conversion process of transient light spectrum measuring is analysed in detail, and a S/N expression of transient light spectrum, image parameters, electron optic imaging and effect of CCD lightsensitive surface are described. Finally, the measured spectrum curves are given.

    Jan. 01, 1900
  • Vol. 21 Issue 7 825 (2001)
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