This paper reports a method for obtaining high phase-conjugate reflectivity, which combines two-wave coupling and self-pumping effect in a BaTiO3 crystal. The dependence of the phase-conjugate reflectivity upon the beam intensity ratio and the angle between two coupled beams are given. Experimental results show that under proper conditions the phase-conjugate reflectivity is greater than 35.

This paper presents a method in which the relaxation time of Kerr liquid comparable with pulse width nitrobenzene is measured and the results is agreeable to the results obtained from the references.

High-lying levels of atomic Gd in the range of 34463cm-1-35628cm-1 have been measured from the initial energy level 999cm-1 by resonant multi-photon ionization (EMPI). 19 high-lying levels have been detected and 11 levels of them are reported for the first time.

We have studied transient absorption of the conducting polymer MP-PPV in solution and film after picosecond UV pulse excitation. Four transient absorption bands have been observed in dilute solution and assigned to polarons and bipolarons. Generation, transport and decay of these elecmentary excitations are influenced by experimental conditions.

Measurement of P-I (power-current) curves of the semiconductor laser in an external cavity may lead to the determination of such diode parameters as the absorption coefficient a, the differential small signal gain coefficient dg/dI and the photon lifetime τ. As a result, a simple and easy method has been proposed to designate some important parameters of semiconductor lasers.

A novel synthetic multi-slit rainbow achromatic image holography is proposed. Some discussion on the achromatic condition and the image blur caused during two-times exposure when recording is also made. Finally the limits to the turning angle of object wave-surface are given.

Multiple-valued optical logic implementation have firstly been demonstrated by using bistable laser diode (BILD) or bistable light emitting diode (BILED) circuits. Experimental results have demonstrated the basic ternary logic functions: complement, minimum, maximum, cycle and literals. A circuit design of ternary T-gate or triplexer has also been proposed.

A high diserimination intensity optical correlation system is presented. By using a lensless spatial differentiation filter to realize edge enhancement for the input images, the discrimination of the intensity optical correlator with the Fresnel holographic filter is improved. Theoretical analysis and experimental demonstrations are given.

A new method is described which can attenuate zero frequency component of object spectrum by polarization spatial filtering in a white-light image processor so that image edge enhancement is obtained in real-time. It can be made easily and the contrast of edge enhanced images can be controlled continuously.

Proposed in this paper is a technique for adding more color secrets in rainbow holograms. The key points of this method are that by means of traversing area partition of master hologram and synthesis of the dispersion viewing window, a special chromatic order in reconstructed image will be resulted. In addition, the basic principle, the chroma calculation and the experiments are presented.

The microstructure and thermal stress fatigue property of 4Cr5MoVlSi steel subject to laser surface melting-solidifying were studied. The results showed that the laser surface melting-solidifying microstructure can inhibit the initiation and extension of thermal stress fatigue crack.

A novel optical oscillator with photorefraetive gain are presented and constructed for the first time. A theory about the oscillator is built up under strong pumping condition. Its output characteristics in steady state have been researched experimentally.

It is shown that a high nitrogen partial pressure carbon dioxide laser without water cooling can be operated at any nitrogen concentration and the output power can be kept almost constant by selecting an appropriate total pressure for a given mixture.

Using the diffraction, integral equation, the irradiance in near -field , i. e., in the region between the aperture and the Fresnel region, of plane-wave Gaussian beams are presented for the first time. Some new results for Fresnel diffraction characteristics of Gaussian beams are obtained. For comparison, the incidences of plane and spherical wave are also analyzed.

A simplified method is presented for analysing the propagation characteristics of trapezoidal cross-section dielectric optical waveguides by the effective index method and WKB theory, and the approximate mode equation is derived for calculating the Emnx mode effective indices. Computed results from this mode equation are in agreement with the numerical ones of the finite element method as well as the experiments.

Third-order nonlinear optical properties of Fe2O3 colloids were studied with degenerate four wave mixing. It showed that the third-order optical nonlinearities were enhanced clearly after Fe2O3 small particles were claded with a layer of polar molecules, and their third-order nonlinear optical coefficient X(3) for the hydrosol and the organosol were 1.3×10-10 esu and 2.3×10-9 esu respectively. And the enhanced mechanism of the nonlinear effect was analyzed.

Intense spontaneous amplified radiation at 241.2 nm and 268.7nm were first observed in He/Ar/Kr/F2 mixture and atmosphere excited by fast discharge. Approximate calculation indicated that the spectra at 241.2 nm and 268.7nm belong to NF and OF respectively.

The effect on LPX radiation characteristics with a laser irradiating binary-layer (Au-Al) target is presented with or without a prepulse in this paper. It shows that abundant spectral lines of H-like aluminium ions and a varitey of impurity spectral linesemitting from the inner layer of Al are observed with a high spectral resolution due to the narrow linewidths. While without prepulse and the thickness of the outer layer of Au coated more than 200nm, only gold spectral lines emitted from the outer layer of Au coated more than 200 nm, only gold spectral lines emitted from the outer layer of Au are observed.

This paper derives the general formula for variation of dielectric tensor, caused by the linear electro-optical effects in crystals. The changed matrix of dielectric tensor for the point groups of the main photorefractive crystals have been given.