The analytical solutions of electromagnetic wave equations for double clad elliptical optical waveguide have been studied. The mode field distribution and the mode characteristic equations are obtained. The numerical solution for charactistic equations of fundamental modes are derived. The normalized birefringence and modal dispersion as functions of normalized frequency for different aspect ratios are presented and compared with Guassian approximation.

An otpical transfer function and its image quality criterion developed which consist of wave aberrations and roughness errors. And the tolerance theory of roughness is discussed.

Based on the analysis on the general red sensitive dichromated gelatin (MBDCG) systems having lower sensitivity than dichromated gelatin, a new method for strengthening its sensitivity is presented herein. The sensitizing machanism and the results of the experimental verification are discussed. The practical sensitizing result by this method is investigated as well.

A cooperative target recognition technique based on laser beam coding is presented in this paper. As a result, the problems such as electromagnetic interference and garbling which exist in airwave target recognition can be solved. The recognition resolution can be improved and bit error rate can be reduced by this way. A laser modulated M-sequence coder is designed for target recognition system, thus recognition security and quality of Question and Answer signals can be increased greatly.

This article studies the recipe of constructing Self Fourier Functions(SFFs). A method complementary to the Caola′s is given as f(x)=g(x)g(-x)+g F(x)g F (-x).  Its advantage and disadvantage are discussed. The simplest expression of constructing recipe for SFFs is deduced.

A transmissive two dimensional nonlinear thresholding liquid crystal light valve has been fabricated. Each pixel occupies 20 μm× 20 μm square and consists of a photodetector and control electrode pad. Its electrooptics, photooptics, and thresholding feature is measured.

A new image nonlinear segmentation method based on multilayer neural network is proposed in this paper. The technique of improving the learing speed and the method of selecting learing patterns are discussed. The experiment shows that proposed multilayer neural network can be used for real time image segmentation and the good results can be obtained.

A new type of laer locking technique for small sized TEA CO 2 laserscomposite cavity injection locking and its principle are presented. The frequency characteristics of a composite cavity injection laser are analyzed theoretically. The preliminary experimental results of the locking technique are given.

The coherence length of a laser diode can be reduced by modulating the source with a high frequency signal superposed on the driving current for the laser diode. Experiments are made with a 980nm laser diode. It is shown that the coherence length has been reduced by 20 times.

Laser quality single crystal of Nd∶SVAP was obtained by Czochralski method in our laboratory. Room temperature polarized absorption and emission spectra of the X(a) axis cut and Y axis cut samples are analysed in this paper, and the laser characteristic of the two differently cut samples are studied.

The utilization of cellular automata phase unwrapping method in 3 D sensing of complex object shapes has been studied. By constructing binary control mask using intensity modulation analysis method, we can unwrap complex phase maps. The experimental results of a human jaw model are given.

In order to study the feasibility of submicron lithography using second harmonic light of a copper vapor laser(CVL), a 1∶1 catadioptric projection lens, and an illumination system which consists of a rotating diffuser and a ligth pipe, are designed and constructed. A resolution of 0.6 μm line/space patterns is produced in AZ1350 resist. The result shows that the second harmonic light of CVL can be used as an illumination source in submicron lithography.

Based on the couple wave theory of waveguide, second harmonic generation (SHG) efficiencies of planar and channel waveguides have been deduced for the specific structures of the two waveguides. The effects of various factors on SHG efficiency of the waveguides were discussed. Mg∶LN and LT waveguides were fabricated by ion exchange and their SHG properties have been measured and discussed.

This paper gives a method of chaos control to acousto optical bistable (AOB) system using the technique of continuous parameter delayed feedback. Numerical results show that under some stiffness of control the controlled system has negtive maximum Lyapunov exponent (MLE) in the initial chaotic domain and so that controlled state is convinced to be the unstable fixed point or unstable periodic orbit (UPO) of the initial system. By comparied with the experimental results, the validity of this control method is verified.

Organic polymers are attractive nonlinear materials because of their both large nonlinear coefficient and ultrafast response time. By use of the modified nonlinear Schrodinger equation, we have investigated numerically the effect of delayed nonlinear response time, as well as second and third order dispersion, on the propagation of femtosecond optical pulse. It has been shown that the red shift due to delayed nonlinear response time in frequency domain increases with the increasing of delayed nonlinear response time exceeds a certain value.

CW laser induced thermal and mechanical damage in optical window materials are investigated. Inhomogenous absorptance will result in thermal stress in optical materials, which seriously induced macrodamage, fusion or fracture. Thermal and mechanical damage are related to laser power and thermal properties of materials. Ion exchange treatment was used to strengthen glass surface.

Generation of visible light at 588 nm with peak power as high as 20 W through efficient frequency upconversion of 1.313 μm  Q switched  and mode locked Nd∶YLF laser pulse in a standard communication single mode germanosilicate optical fiber is reported. The conversion efficiency is measured to be 0.09% in 21 m fiber at 24 kW peak pump power. A blue green light with multi peak continues spectrum structure at 46￣560 nm generated by three wave sum frequency is also observed. The frequency upconversion process of blue green light is competing with the process of generation visible light at 588 nm.

Ionization dynamics is investigated for intense laser gas interaction, in which tunnelling ionization is assumed to be the dominant process. The electric filed perodic variations of laser by tunnelling ionization is calculated. The harmonics obtained by Fourier series decomposition.

The relationship between the light propagation effects in the turbulent atmosphere and the path integral parameters of the refractive index structure constant C 2 n is analyzed with the theory of light propagation in the turbulent atmosphere. The path integral parameters of C 2 n corresponding to the coherent length, the fluctuation of the arriving angle, the spreading and wandering of light beam are obtained with the equivalent refractive index structure constant derived from the measurement of the light intensity fluctuation, and the relative differences of these parameters with true values are evaluated. For periodic, decreasing, increasing, and random turbulent paths the relative differences are calculated as functions of various path parameters. The relative differences for the periodic turbulent path increase with the amplitude parameter and behave as damped oscillations with the frequency parameter. The relative differences for the decreasing and the increasing turbulent path are quite high. For a random turbulent path, the relative differences fluctuate with time series number and their statistical average values decrease with the number of the independent turbulent intervals. Suggestions for the accurate evaluation of the optical turbulence effects are given according to the results.

The characteristics of noise and distortion on an erbium doped fiber amplifier (EDFA) are investigated experimentally for using in optical FM frequency division multiplexing (FDM) video systems. The transmission experiment at the signal noise ratio of 56 dB over 180 km and 215 km were performed by using EDFA as a post amplifier and an in line amplifier.

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.

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.

Photoinduced optical anisotropy in Y type interleaving hemicyanine/arachidic acid Langmuir Blodgett multilayers has been investigated by optical linear and nonlinear measurements. Under illumination of a polarized UV nanosecond laser beam, the hemicyanine molecules would reorient and align their chromophore axes along the direction of the UV beam polarization. Thermal isotropic process was accompanied by dissociation of the H aggregate in the hemicyanine LB multilayers.

In this paper, we analyze the mechanism of the probe doped layer measurement to study the excitation efficiency distribution across the phosphor in thin film electroluminescent devices. The characteristics of excitation efficiency and its distributionacross the phosphor are measured in low voltage driven thin film electroluminescent devices fabricated in our laboratory. The experimental results prove that the excitation efficiency across the phosphor of the device is not homogeneous, and its variation depends on the applied voltage. We infer that the low-voltage-driven thin film electroluminescent mechanism is attributed to inhomgeneous distribution of electric field in the phosphor.

The optical properties of monolayer GeSb 2Te 4 thin film prepared by vacuum RF sputtering method at the region 400～830 nm were studied. A comparatively large absorption was observed in the wavelength range of 400～600 nm. The optical storage characteristics of GeSb 2Te 4 thin film indicated that larger reflectivity contrast can be obtained at lower writing power Argon laser (514.5 nm) . The erasing reflectivity contrast is low, but it can be improved by multi layer films match.