The formation and development of detects in Nd:YAG crystals grown by TGT have been studied systematically with different methods. According to the defect formation mechanism, the high quality area within crystal boules can be enlarged notably after reasonable modification of the growth parameters. Single transverse mode and single longitudinal mode laser output have been obtained easily from high dopant （Nd2O3 1wt％） and high optical homogeneneous laser rods. However, the effect of interference fringe distortion due to the growth strie in the crystal on the beam quality from disk laser and the laser threshold remain to be improved.

Origin of sharp luminescence lines in BeO·3A12O3:Cr3+ crystal, several different luminescence centers were found, and the energy transfer models among different Cr ion centers were put forward.

Theoretical analyses and experimental verification of the pseudo-coloring principle of density were made by regarding an encoded phase-picture as an interference filter and some meaningful results wore obtained.

A novel holographic phase conjugated mirror is put forward. Conjugated light wave could be obtained directly when the phase conjugated mirror is illuminated by the corresponding original object light wave.

Single tier high frame is a typical frame of factory building. It is necessary to determine natural vibration property of the frame in earthquake-resistant design. We have studied natural vibration property of the frame by laser holographic interferometry. The results show that this method is useful in studying these problems.

Experimental procedure is presented in 20# steel surfaces of carbonitriding and carbo-boronization by employing a transeversely-excited CO2 laser. The results indicate the chemical composition and microstructure in the laser penetrated layers has undergone a radical change and its hardness and resistance to abrasion have been greatly improved.

A virtual concentric resonator has very good mode-selection ability. The eigen solutions of the field distribution of a virtual concentric resonator have been derived in the paper by using fundamental mathematic processing.

The dependence of pumping time of light pulses of 510.6nm and 578.2nm copper vapor laser lines on neon pressure and discharge voltage has been measured. The pumping time of 578.2nm laser pulses with different neon pressures decreases as the discharge voltage increases, and that of 510.6nm laser line is more sensitive with respect to neon pressure.

Starting from modified Fourier heat conduction law, the propagation law of thermal shock-wave produced by laser light on one dimensional semi-infinite medium is discussed. Analytical expressions are obtained on short time and long time approximations. The short time approximate solution represents non-Fourier behaviour and the long time approximate solution degrades into thermal coupled wave solution in classial heat conduction law.

Physical meaning of weak-Gaussian aperture approximation and the fundamental characteristics of PCRs are discussed in detail. The conditions for compensating intracavity distortions of PCRs is derived by using the transfer matrix method. Properties of PCRs are essentially different from those of conventional resonators.

This paper reports two new scattering rings that appear when an extraordinarily polarized laser beam is incident on a thin sheet of LiNdO3:Fe crystal and discusses the mechanism leading to the phenomenon.

Experimental results on a Compton free electron laser are reported. Free electron radiation with an average power of 1.4W at 10μm was obtained when 22MeV relativistic electron beam was injected into the SmCo5 permanent undulator with 3cm period for a total of 98 periods by a linear accelerator.

Analysis in this paper shows that a harmonic measurement method can be used to determine accurately the threshold current of semiconductor lasers. The experimental method and results are given and compared with those of other methods.

It was found that the annular structure of the stimulated emission is mainly due to nonuniform decay of the lower active level or the ground state "thermal dumping" resulting from excessive heat in axial region of the discharge tube.

Raman shifted convesion from AS3（226 nm） to S5 （849 nm） have been observed in high pressure H2 pumped by high power XeCl eximer laser radiation （308 nm）. Its photonconversion efficiency into blue-green region （S3, 499nm） was obtained up to 39％. Relaxation oscillations of higher order Raman shifted emissions were obtained and analysed.