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

In this paper, we propose a shift and rotation invariant pattern recognition architecture, using morphology pattern spectrum as image feature representation and 2-D vector quantization network as vector classifier. Morphology pattern spectrum is invariant not to image shift, but to image rotation when the structure element is rotationally symmetric. We use it constructing a feature vector of an image to train a 2-D vector quantization network. After training, it can implement the classification of feature vector. The optical implementation of the 2-D vector quantization network is dementrated and the experiment results are given.

Jan. 01, 1900
  • Vol. 16 Issue 6 763 (1996)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The phase-shifting holographic CT technique is presented in this paper. Using two- reference-beam phase-shifing method and introducing phaseshifts during reappearance, we reconstruct the temperature field of two-candle flame. The results show that the phase distribution in certain projection direction was obtained repidly and accurately by this technique. It is satisfield for reconstruction result.

    Jan. 01, 1900
  • Vol. 16 Issue 6 768 (1996)
  • [in Chinese], and [in Chinese]

    A new kind of optical neural network for associative colors using high resolution liquid crystal televisions (LCTV) is proposed and constructed. This new model adopts the multivalued neural algorithm based Hop field feedback associative memory model. The system design consideration and an experimental demonstration of the LCTV neural network are provided.

    Jan. 01, 1900
  • Vol. 16 Issue 6 772 (1996)
  • [in Chinese]

    The principle and fabrication of the phase quadrature laser interferometer for measuring microscopic asPerity are described. The behavior of the novel interferometer and some problems are discussed.The calculation of the measured result and sample scanning in the interferometer is performed by a PC computer. Vertical resolution is 1 nm, and lateral resolution is 10 μm. The result shows the good stability of the system.

    Jan. 01, 1900
  • Vol. 16 Issue 6 812 (1996)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    A novel mothod of intensity modulated optic displacement measurement is described. A LED is used as source. The ray projects from the first SELFOC lens, then is reflected by the mirror and enters into second SELFOC lens. When the mirror has some little displacement, the ray entering the second SELFOC lens is modulated. The value of displacement is determined according to the change of light intensity with photocell. A resolution of 1×10-9 m is attainable with this metering device. The principle can be also used in the measurement of pressure and vibration.

    Jan. 01, 1900
  • Vol. 16 Issue 6 816 (1996)
  • [in Chinese], [in Chinese], and [in Chinese]

    Based on the Cerenkov radiation of electrons from the Compton scattering of the X-ray in optic fiber, an optic fiber X-ray probe and measurement system can be constructed. The theoretical and experimental study have been conducted. The analytical expression for the sensitivity of the probe is deriven and its calculating result is given. We have made the caliberation experiment and discussed the measurement dynamic range and time response of the system.

    Jan. 01, 1900
  • Vol. 16 Issue 6 822 (1996)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    A accurate and simple inethod for calculating the propagation constunt of Ti: LiNbO3 waveguide is suggested according to the property of refraction index profiles. The method is analysed and the dispersive relation of Ti: LiNbO3 waveguide is calculated by this method. It provides a theoretical approach to design Ti: LiNbO3 integrated optical devices.

    Jan. 01, 1900
  • Vol. 16 Issue 6 801 (1996)
  • [in Chinese], [in Chinese], and [in Chinese]

    Continuous radiation from a new kind of ionic excimer, krypton fluoride, was observed under the excitation of soft X-ray from laser produced plasma. The peak of the radiation is near 148 nm. The kinrtics is studied theoretically and experimentally.

    Jan. 01, 1900
  • Vol. 16 Issue 6 705 (1996)
  • [in Chinese], and [in Chinese]

    Idealizing the radio-frequency (RF) modulating ultrashort electron pulse as a δ time function, we analysize theoretica1ly the coherent synchrotron radiation emitted by the high bunched electron beam and its frequency properties in a reetangular waveguide. We find two new performances: (1 ) when the resonance frequency fs is just equal to integral times of radio frequency fRF which is applied to modulate electron beam, the coherent synchortron radiation field pattern appears "pure" waveguide eigenmode; (2) the coherent synchrotron radiation power at low resonance frequency is higher than that of at high resonance frequency. In addition, we predict the condition for single mode transverse operation in a waveguide FEL.

    Jan. 01, 1900
  • Vol. 16 Issue 6 711 (1996)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The beat frequency characteristic of a He-Ne laser with an activity plate in its cavity is studied. The laser physics and crystal optics are used to solve the problem. One mode of laser splits into two eigenstates of crystal as it transmits in the plate. G is the ratio of them, so the time delay of the mode is between those of two eigenstates. The time delay of another mode is also between those of them. So that, the beat freauency is always less than what is determined by the phase difference of two eigenstates. It is related to the special factor G2. Theoretical result matches the experiment very well.

    Jan. 01, 1900
  • Vol. 16 Issue 6 716 (1996)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The mechanism of trap effect in the process of photoconductivity of photorefractive materials is proposed in this paper. The kinetic equations of carrierls light stimulating, recombination, and trapping is presented, and the theoretical expression of the quantum efficiency of photogeneration with trapping effect is obtained. In experiment, the dependence of the quantum efficiency of PVK thin film doped C60(C70)of different concentration has been measured, and the result is. good agreement with the proposed theory.

    Jan. 01, 1900
  • Vol. 16 Issue 6 870 (1996)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    Fe: BSO crystal has been grown by doping Fe2O3 into BSO. Because of the defect energy level in forbiden band induced. by Fe impurity, the photorefraction properties of the crystal, such as diffractive efficiency and four- wave mixing phase conjugate reflectivity, have been greatly improved. The defect energy level of Fe impurity is identified according to the absorption spectra.

    Jan. 01, 1900
  • Vol. 16 Issue 6 874 (1996)
  • [in Chinese], [in Chinese], and [in Chinese]

    An ultra-sensitive imaging system with photocathode sensitivity of 0. 5 cps/mm2 has been developed to obtain the ultra-weak bioluminescence images of a sprounting Mung bean and a living Kunming mouse, and analysis with statistical theory was given for signal testing in these ultra-weak images. In this paper we analyzed the statistical judge to decide whether or not there is signal burying in noise under the condition that both signal and noise obey Poisson probability law, and discussed the five factors which have effects on the judge. With this judge, we have succeed in finding signal in the image of ultra-weak bioluminescence emitted by a living Kunming mouse.

    Jan. 01, 1900
  • Vol. 16 Issue 6 806 (1996)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The efficient generation of amplified spontaneous emission (ASE) in 2- (2'- hydroxyphenyl) benzoxazole (HBO) in cyclohexane solution based on excited state intramolecular proton transfer (ESIPT) is reported. The gain coefficient (α) for ASE(510 nm) of HBO is measured as about 1. 2 cm-1, nearly equal to that of rhodamine-6G under similar conditions in our apparatus. Based on ESIPT processes of HBO, a kinetic model for ASE is developed to simulate numerically the gain spectra and ASE spectra. The agreement between the computed results and experiment is very satisfactory with a τs0s0' value of 260 ns. This fact sugguests that the lifetime of ground state keto tautomer (K) is more likely to be 260 ns rather than subnanosecond.

    Jan. 01, 1900
  • Vol. 16 Issue 6 738 (1996)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    In this paper we discuss the influence of thermal lens effect on the Kerr lens mode-locking in a solid-state laser system containing an extra nonlinear Kerr medium.The conditions of the Kerr lens mode-locking insensitive to thermal effects are analytically obtained. The corrections of the design parameters for a typical resonator are given by means of numerical studies.

    Jan. 01, 1900
  • Vol. 16 Issue 6 746 (1996)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The SRS propagation modes in single-mode polarization - maintaining optical fibers were experimentally studied. The SRS spectrum and mode profile of three different cut-off wavelength fibers were obtained and the experimental results were completely different from those in circal-core graded-index optical fibers. The size of SRS beam remains nearly constant and they were characterized by the propagation with higher order mode. These results have not be seen both home and abroad.

    Jan. 01, 1900
  • Vol. 16 Issue 6 751 (1996)
  • [in Chinese], and [in Chinese]

    The computer simulated dynamic light scattering signal of small particles (0. 00l μm~ 1 μm) is obtained and analysed. From these signals, the size information of small particles can be investigated. Also the fractal concept is used to analyse the time complexity of these signals, and to obtain the relationship between fractal dimension and radius of partcles.

    Jan. 01, 1900
  • Vol. 16 Issue 6 755 (1996)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    Third-order optical nonlinearities of salts of planar complex cations and planar complex anions were studied by DFWM at 1. 06 μm. It was found that these compounds exhibited large nonlinearities in time scale of ns, and that within the molecules of the same series, the molecule with metallic ion of larger atomic number possessed larger nonlinear hyperpolarizability γ1111.

    Jan. 01, 1900
  • Vol. 16 Issue 6 759 (1996)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The application of a novel linear tricolor sampling leaf-shape grating to onestep in formation recording on a monochrome film is proposed. In this paper, it is proved that the proposed application can make the recording and retrieving simple and economical to implement, the color-cross-talk, Moire fringes and marginal loss in resolution avoided, the mutual modulation cleared up, the utilization ratio of light energy improved greatly.A method of computer generating the linear tricolor sampling leaf- shape grating is presented and the potential application to holography and optical information processing is also discussed.

    Jan. 01, 1900
  • Vol. 16 Issue 6 827 (1996)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    In this paper, the analytic expression of diffraction efficiency corresponding to the mask etch-depth errors is deduced from the scale diffraction theory. Choosing 4-step and 8-step blazed grating as an example, we simulated systematically main registeringetch errors and their interactions of binary optical element using computer. The results of computer simulation agree well with that of the analytic method. It can provide theoretical basis and experiment parameter for practical fabrication.

    Jan. 01, 1900
  • Vol. 16 Issue 6 833 (1996)
  • [in Chinese], and [in Chinese]

    The GexSi1-x/Si strained-layer superlattices avalanche photodetector has been studied and optimum designed. Its optimum structure parameters are: the thickness of i-Si avalanehe region is 1. 8~2 μm; the carrier concentration of p-Si region is 10 18 cm-3 and thickness is 17 nm; the total thickness of superlattices is 340 nm. The detector can be operated in the range of 1.3~1.6 μm.

    Jan. 01, 1900
  • Vol. 16 Issue 6 839 (1996)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The deviations of wedge angles to some extent between the actual value and accurately theoretical value are made purposely during processing the segmented wedge array line focussing system in order to improve the large-scale nonuniformity caused by unit diffraction. In this paper, theoretical calculation and experimental verification are made, and the reasonable deviation datu are given in the case of improving the uniformity while ensuring certain utilization ratio of line focus energy. It provides a necessary basis for the optimization design of uniform line focus system.

    Jan. 01, 1900
  • Vol. 16 Issue 6 844 (1996)
  • [in Chinese], [in Chinese], and [in Chinese]

    The characteristics of a Lyot optical fiber depolarizer has been investigated theoretically and experimentally. The formulas with respect to the degree of polarization and the corresponding parameters have been derived and discussed for the frist time. Experimental results verified the validity of this depolarizer architecture. A depolarizer with a degree of polarizationof 2. 0% has been obtained.

    Jan. 01, 1900
  • Vol. 16 Issue 6 848 (1996)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The properties of liquid crystal light value (LCLV), including the response curves between input and projection beam in real, inversed, and differential state, also the relationship between the transmission of the liquid crystul and the working voltuge when different input beam lumination provided, are measured by facile method. The analysis to the experimentul results revealed the nonlinear transforming properties of LCLV, which have not been thoroughly researched be fore. A solid base for a great deal of its applications is provided and the direction of further development is presented.

    Jan. 01, 1900
  • Vol. 16 Issue 6 853 (1996)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    A novel fiber optical tupered coupler is proposed with its waveguide refractive index gradually changing, induced by germania defects under the UV irradiation. The refractive index change An of 6 ×10-3 in the, single- mode communications fiber is achieved in our experiment by means of pre-treating the fiber in high-pressure and lowtemperature environment. A particular index tuper profile function is obtained by delicately controlling the exposure conditions, and the mode field radius (MFR) is reduced from 4.8 μm to 3.2 μm in single-mode fibers. The coupled wave theory analysis show that the tapered coupler is capable of excellent transmission for fundamental mode with very small mode conversions.

    Jan. 01, 1900
  • Vol. 16 Issue 6 857 (1996)
  • [in Chinese], and [in Chinese]

    On the basis of the experiments for silicon and GeSi electro-optic modulator, a new type od electro-optic modulator is proposed, in order to decrease the modulating current and increase the modulating frequency.

    Jan. 01, 1900
  • Vol. 16 Issue 6 862 (1996)
  • [in Chinese], [in Chinese], and [in Chinese]

    A new binary joint transform correlator (BJTC) with high pass filtering is.proposed. The difference between the proposed correlator and BJTC is that joint power spectrum is processed by using high pass filtering before applying binarization. The technique is found to yield significantly better correlation output performance than the AJTC. Comupter simulated results for input scences with gray-scale objeet are given.

    Jan. 01, 1900
  • Vol. 16 Issue 6 866 (1996)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    We present a computer simulation and an experimental demonstration of the formation of Bravais lattices by multiple laser beams. It is shown that most of the Bravais lattices can be created by four or six laser beams. The body centered, the hexagonal close-packed, and the face centered structures have been specially demonstrated by using a He-Ne laser. The measured lattice constants are coincident well with the calculated values. This study will be helpful to the realization of photonic crystul in visible and infrared region.

    Jan. 01, 1900
  • Vol. 16 Issue 6 797 (1996)
  • [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.

    Jan. 01, 1900
  • Vol. 16 Issue 6 877 (1996)
  • [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.

    Jan. 01, 1900
  • Vol. 16 Issue 6 881 (1996)
  • [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.

    Jan. 01, 1900
  • Vol. 16 Issue 6 885 (1996)
  • [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.

    Jan. 01, 1900
  • Vol. 16 Issue 6 889 (1996)
  • [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.

    Jan. 01, 1900
  • Vol. 16 Issue 6 893 (1996)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    According to the periodical property of temporal coherence g(1)(τ) in a multimode gas laser, a new method of observing the spectral line-shape function and its frequency width of longitudinal mode in a multi-mode laser is proposed in this paper. The investigation shows that the spectral line-shape function of longitudinal mode in the multimode gas lasers is Lorentz line- shape function, and relative frequency width of longitudinal mode is about 107 Hz.

    Jan. 01, 1900
  • Vol. 16 Issue 6 721 (1996)
  • [in Chinese], [in Chinese], and [in Chinese]

    The Raman scattering measurement of ammonium hexachloroplumbate crystal has been presented. A second order structural phase transition from cubic (O5h) to trigonal structure (C23i) at Tc = 78 K was observed in this crystal. The Raman frequency shifts of the A1g mode of the PbCl2-6 octahedron and A1 mode of the ammoium tetrahedron have a maximum value at Tc Line splittings of the T2g mode of the PbCl2-6 octahedron, the Tzmodes of the ammonium tetrahedron and the external vibrational T2g mode have been observed below Tc, along with a soft mode corresponding to the T1g mode of the PbCl2-6 octahedron in the heigh temperature phase.

    Jan. 01, 1900
  • Vol. 16 Issue 6 727 (1996)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    The spectra of helium and kryton excited by alpha-particles (~ 5. 5 MeV) emitted from 238Pu have been measured using a home- made single- photon counting system. Thirteen spectral lines of helium between 370.0~720. 0 nm are identified, five lines of them belong to HeI's spectra, the others are the vibronic spectra of helium moleculars ; and seven spectral lines of kryton between 400.0~600.0 nm are observed. The spectral intensity varied with gas pressure have been given for He and Kr, respectively. The possible atomic and molecular processes by alpha-particles impaction are discussed.

    Jan. 01, 1900
  • Vol. 16 Issue 6 732 (1996)
  • [in Chinese], and [in Chinese]

    On the basis of full consideration to interface absorption in optical coatings, we worked out a model of simulative interface absorption layer. Calculation and analysis of the temperature field are made for some kinds of multilayers. The real-time results from laser induced damage to samples using photothermal deflection technique support this model.

    Jan. 01, 1900
  • Vol. 16 Issue 6 777 (1996)
  • [in Chinese], [in Chinese], and [in Chinese]

    We have established a new equipment── physical jet deposition system (PJD), and successfully manufactured thin films such as C60, C70, PVK and PVK/C60 combination film by this new system. Based on the comparison of the absorption and photoluminescence (PL) spectra of these films with those of deposited films in normal high vacuum system, we found that the thin films with fine quality and high damage threshold can be made by this new PJD method. It is shown that PL decay behaviour of C60 PJD film is quite different from that of normal C60 film. In the PVK/C60 combination film, charge transfer complex has been observed.

    Jan. 01, 1900
  • Vol. 16 Issue 6 783 (1996)
  • [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    GeSbTe is the most suitable media for PCE (phase change erasable optical disc) at present. By using the PCE dynamic testing equipment, experimental study on dynamic overwriting characteristics of the GeSbTe PCE discs made by our institute is conducted. The results show that it could be direct overwrited for several times, and better erasing effect with much more overwrite times could be achieved when pulse erasing method was used instead of continuous erasing method.

    Jan. 01, 1900
  • Vol. 16 Issue 6 787 (1996)
  • [in Chinese], [in Chinese], [in Chinese], [in Chinese], and [in Chinese]

    A double layer electroluminescent (EL) device is constructed by using a lundnescent layer, 8-hydroxyquinoline aluminum (Alq3 ), and a hole-transport layer,microcrystul diamond film. The EL spectrum, the J-V and B-V characteristics have been measured, and the quantum efficiency has been calculated. It .is showed that the current of the device with diamond film is lower than that of single Alq3 layer device but the quantum efficiency is higher than single layer device. A energy band model has been estublished, and the exprimental results has been well complained.

    Jan. 01, 1900
  • Vol. 16 Issue 6 793 (1996)
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