A method is given in this paper using incoherent light to realize 2-D complex discrete Fourier transform (DFT). A multi-imaging system is set up, which fully uses the inherent property of optical parallel processing, and 2-D input data can be processed simultanously. A complex can be optically expressed by two encoding methods. 2-D input data of N = 6 is chosen to verify the method. The experimental results accord with the simulant results of computer.

A simplified white light correlator with a compensation grating has been developed and proved to be effective for particle sizing when high pass filtering is adopted during MSF fabrication. Both the theoretical analysis and experimental results are presented in this paper. By using this technique the soze of objects with the annulus shape can be determined to the accuracy within 1-2% relative error.

Eeported in this paper is a cheap, compact and convenient spatial light modulator ——liquid crystal television (LOTV). Conversion of incoherent to coherent of image by the LOTV is obtained. A joint transform optical correlator with BSO crystal implemented real-time cross correlating operation on diffuse object.

Statistical properties of dye laser transients are analyzed by first-passage-time technique. Both pump and quantum fluctuations effece the establishment of steady states in a dye laser. These two kinds of noise play different roles in laser transients. Meanwhile it is difficult to discern them since the pump fluctuations are six orders of magnitude larger than the quantum noise. In this paper a model of single mode dye laser with pump fluctuations simplified by white noise is presented and the analytic results of the mean, variance and skewness of first-passage-time distributions are obtained through a Fokker-Planok equation. Compared with, experimental measurements and curves from Monte Carlo simulationsi, excellent agreement is obtained.

In this paper, a copper hollow cathode laser with all metal construction is presented. The laser has advantages of high resistance to high temperature roast and stable structure. Discharge stability is greatly improved. Two laser oscillations of Cu II 740.4nm and 780.8nm are obtained. Some new results are given through investigation on threshold feature of the laser, effect of gas mixture ratio and discharge temperature on the laser output power etc.

The intensity dependence of two-color laser single resonance UV photon ionization of gag phase CS2 and the features of resonance ionization of higher excibedstate (1∏g) are presented in this paper.The experiment shows that the total ionization cross-section of three-photon ionization with two-photon resonance excitation via the intermediate state, 1∏g, is higher than that with one-photon resonance excitation via the lower state, a-3A2.The saturation effect was observed under the laser intensity of 107W/cm2. The results indicate that by measuring the intensity dependence of two-color laser single resonance ionization, a new method for speotrosoopio analysis was deveilopsi. This would be signifioan b in the study of molecular structure at high excited state.

Optical multiatability, optical XOR logic gate and R-S flip-flop have been demonstrated using composite hybrid bistable laser diode or light emitting diode (BILD/BILED) circuits. This kind of optoelectronic logic circuit is fully compatible with VLSI technique and therefore promising for the application to optical signal processing, optical communication and optical computing.

The physical and mathematical models of CO2 laser with feedback control of detuning has been set up. The analysis of steady state shows that the optical Disability between the pump rate and the output intensity of the laser will appear when the feedback coefficient exceeds the critical value. Eesults of linearized stability analysis indicate that the necessary condition of the dynamical instability is that the Debye-relaxation rate of the detuning (bandwith of the feedback circuit) must exceed the decay rate of the population invergion. The instability appears only when the laser pump falls into a proper region. The behaviours of the period-doubling "bifnroation and chaos have been pfbved by the result of numerical calculation. The frequency of the Hopf bifurcation predicated by the stability analysis is oonaiatent with that given by the nnmerioal calculation.

Soliton interaction with chirp from optical source in nonlinear monomode optical fibers is studied numerically by using slit-step Fourier transform method in detail. The results show the essentiality of the influence of optical source chirp on soliton interaction, and provide the foundation for the design of soliton transmission systems in the existence of optical source chirp.

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.

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.

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.

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.

The picosecond time-resolved fluorescence spectra are measured for DCM, orysel violet, DODCI and DTDCI in polar solvents. The time-dependent spectral shifts (TDSS) are attributed to the dielectric ralaxation of the solvent surrounding the solute molecule, whose dipole moment undergoes pronounced change upon excitation-The relaxation times obtained from TDSS are in good agreement with those calculated from the continuum cavity model, indicating the applicability of the continuum cavity model for the description of TDSS.

A new analytical technique-Photothermal Radiometry (PTR) is introduced in this paper. We set up a PTR measurement system and obtained the optical absorption spectrum of solids by using Ce2O3 powder and a green leaf as the testing sample. Calculated PTR signal-to-noise ratios are found comparable with thsoe observed.

Using picosecond time-resolved transient absorption and fluorescence deoay measurements, the establishment of the triplet state and the deoay of the excited singlet state of TPP-Zn were studied. The inter system-crossing rate, the lifetime and the absorption cross-section of the excited singlet state at 532 nm were deduced.

This paper presnts two kinds of methods for measuring the biaxial single crystal films on the biaxial crystal substroats. We have used such methods to measure the thickness and refractive index of the film layer of KTP waveguide.