The material growth, preparation of Schottky junction and activation technique for a field-assisted heterojunction semiconductor photocathode with 1.25μm threshold have been studied in detail. The photocathode with higher response in the wavelength range from 0.9μm to 1.25μm has been achieved. Utilizing the LPE technology, the material of heterojunction field-assisted photocathode has been obtained with the mismatch rate better than -1.23×10-4. The optimum value (n=1.08) of ideal factor for the field-assisted Schottky junction has been obtained in the UHV system. At 4.5 V bias, the quantum efficiency is 2.5×10-4 at 1.25 μm, which is nearly 2 orders of magnitude higher than that of Ag-O-Cs (S-1) photocathodes at same wavelength.

A new technology for manufacturing spherisal self-focusing planar microlens array by two-step electric field-assisted on exchange method is described in this paper. The theoretic model of this technology is analysed. A sample of spherical self-focusing planay microlens array is successfully fabricated. The parameters and the picture photed the array are presented.

An optical system which can make Gaussien laser beam into square irradiation is studied theoretically in detail, its conclusion is compared with theoretical calculation and experimental results of another similar devics.

A KrF resonator-amplifier excimer laser system using for submicro fine processing was reported. This system can operate in the situation of 200 Hz repetition rate with output power of 24.4 W and spectrum of 2.3×10-3 nm. Its spectrum drift is less 5×10-4 nm during operation.

The resonators bounded by two cylindrical mirrors which are crossed at an arbitrary angle are investigated theoretically by means of matrix theory, The resonator stability, mode distribution and beam propagation chara-cteristics inside the cavity are analysed and illustrated with numerical examples. Our experimental results of a Nd: glass slab laser using the resonator with crossed cylindrical mirrsrs are reporte d and discussed.

Continuously tunable UV radiation is obtained by oollinear doubling and non-collinear mixing from visible radiation of pulsed dye laser. A closed loop method, in which a sample light spot is separated into two equipower parts in the direction perpedicular to phase matching at beginning wavelength of tuning range, then the powers of two parts are compared and balanced in the tuning is reported. This method is analyzed theoretically and demonstrated successfully in our experiment. The auto-tracling efficiency is better than 90%.

In this paper the process of the interaction of two-color pulse laser with multie-lectron atomis studied. The time variations of the population at high-excited state and of the total ion population are calculated and the calculated results are analysed.

The investigation of noncollinear type II phase-matching parametric upconver-sion of CO2 laser in a silver thiogallate (AgGaS2) crystal pumped with a Q-switohed Nd:YAG laser is reported. The computer calculation of optimizing noncollinear angle at which the phase mismatch ΔK is equal to zero is performed. The conversion efficiency was found to be 16.1% for the pump laser of 6MW/cm2 power density in a crystal of 4.7mm long, and the converted radiation was first detected by using a Si avalanche photodiode SPD-052.

Baged on review of the single layer and multilayer models, a general formula of the isoplanatic angle for multilayer atmosphere is presented, which includes the result from Beckers as a particular one.

The spatial propagation properties of output annular laser beam from an unstable resonator are studied based on Fresnel diffraction integral. According to the position of extreme value point of laser intensity on the axis, the formula used to divide the propagation space of output beam from unstable resonator into near field, middle field and far field is derived. The numerical calculation shows the variation process of output laser beam of unstable resonator from annular pattern on near field, with gradual transition of laser energy in the annular region to the beam's center, to Airy disk pattern on far field. The experimental results obtained in TEA pulsed CO2 laser with unstable resonator are in good agreement with theoretical results.

The 34 layers tapCuPo, the copper tera-4- ( 2.4-ditert-ampylphenoxy) phtha-locyanine, were deposited by the LB technique on the optical glass waveguide of K+ ion-exchange, and a four-layer dielectric waveguide with LB films cladding is formed. The 532 nm line from a YAG laser is used as a light source. The input light with pulse width of 250 ps is coupled into the optical waveguide by a glass prism, and then is passed through the regiod coated with the LB films. In the experiment,a fast optical bistability with the switching off time to 24 ps has been demonstrated.

In the paper, the experiment results of time-serial interferograms of explosive flow field and initial combustion process are presented which are produced by using pulsed YAG laser to detonate initiating agent and obtained with timeserial interferometry. On this basis, a method of fringes curve detecting and the function of double cubic many-knot interpolating splines are used to extract the wave-front of shock wave. With the algorithm of serial wave-front registering the propagation velocity of shock wave is calculated quantitatively. At the same time, the distribution of temperature with the change of time in the process of initiating agent combustion is calculated quantitatively also.

In this letter we report the nonlinear property of pyrylium-doped superpolymer studied by degenerate four-wave mixing (DFWM). The nonlinear susceptibility x(3) of pyrylium-doped polymer is 3×10-10 e.s.u.. The time resolution curve formed by the decay of phase conjugate reflection as a function of the delay of the backward pump pulse in the counterpropagating DFWM scheme was observed, and the relaxation time is 30 ps. The electronic and brientational mechanisms are discussed.

Using a 6.5×9×20 (length) mm KTP crystal, picosecond pulses were obtained with tunable range of 625nm-3575nm, maximum energy conversion effioienoy of -30 %, and maximum peak power of 34MW.

Emission spectra of a low pressure helium microwave-induced plasma sustained by a surfatron were studied with OMA-3. After Abel inversion, the spatial distributions of emission spectrum intensities and excitation temperatures of the plasma were given out at different helium pressures and microwave powers. The exoitating mechanism of the plasma was discussed. The spatial distributions of metable population of the plasma were estimated.

The spetrum for the 6snp Rydberg series of Yb Atom were obtained by using three-step laser excitation. The laser for the first and second step of exoi-tation were oppositely circularly polarized and for the third step was linearly polarized. By the selection rules of the magnetic quantum number m the J value for each spectral line was determined. Some new levels belonging to the 6sns 3Si series (n=26-31) were detected.

This pepar studied pyruvate dehydrogenase using dynamic light scattering (DLS) with photon counting technique and obtained some data on its microstructure. Radii of PDO and E2-X-K are measured. It is found that at lower concentration the aggregation can be neglected, the size distribution is monodispersion, and the linewidths of DLS spectra of PDC and E2-X-K are proportional to q2 and q3 respectively. But at higher concentration the size distribution is polydispers ion and Γ is proportional to qα, where a is fractional.

It is the first time to obtain the Stimulated Rainan Scattering ( SES) in the phenylethanol liquid-core optical fibre by using the frequency-doubling of Q-switched YAG laser (λ= 532.1nm). The fourth-order Stokes line and the second-order anti-Stokes line in this liquid have been observed. The cause of the broaden ings favouring red-shift of the Stokes lines has been discussed.

The studying method of optical thin film loss from the analysis of attenuations of guided waves in the films is presented experimentally in this paper. The advantages and high sensitivity of this method for dealing the loss of thin films have been demonstrated by the experimental results of several low loss thin film samples.

This paper describes the optical Fabry-Perrot cavity made of polymer DR/ PMMA thin film. Prom the observation of the transmission variation with the applied electric field, we can identify the nonlinear optical parameters. For DR/ PMMA we have obtained the third order nonlinear susceptibility x(3)(-ω;ω,0,0)=(5.3-i 6.0) ×10-11e.s.u. and quadratic eleotro-optio coefficient R=-(8.5-i 9.7)×10-19 m2/V2 at 575 nm and room temperature.