The motion equation of the particles is converted into 2nd order ordinary differential equation with a nonlinear term in the frame of classical physics. The solution of equation, and the oscillation period of particles are represented analytically by Jacobian elliptic function and the 1st kind of complete elliptic integral. Some important properties of the radiation are discussed, the maximum radiation energy for the position and the spectral distribution are calculated. The comparison shows essential agreement between the experiment and the theory.

The optical disc and its readout system are analyzed. Rigorous mode method is used to set up a mathematical model of the optical disc diffraction process. The proposed Portran-77 computing programs using the appropriate numerical techniques can provide rapid, detailed and numerical solutions. The computing results are in good agreement with those of experiments.

A new explanation of phase-conjugation (PC) process in backward stimulated scattering (BSS) is given. There are two nonlinear processes occurring simultaneously in BSS: one is pure stimulated scattering,and the other is partly degenarated four-wave-mixing PC process. The close combination of these two processes makes the BSS to be a PC wave to a certain degree. From this point of view we solved the nonlinear coupled-wave equations for the backward SBS and proved that the backward SBS has a perfect PC property only when some particular conditions are satisfied. A four-wave-mixing detecting method was used to investigate this and the experimental results are in good agreement with our theory.

The beam propagation characteristics in the 8-shaped ring resonator containing four mirrors are calculated and comparied with the standing wave resonator by using-three methods: (1) propagation matrix representation; (2) equivalent sequence of thick lenses, and (3) waist position being selected as the reference developing plane. The influence of astigmatism is also discussed.

The characteristics of recombination and emission of light in Cd vapor plasma are studied. The influence of various buffer gases and the gas pressures on the Cd vapor plasma are investigated.

Making use of the liquid core optical fiber formed in the waveguide dye laser t ube, have proved the amplification effect of the evanescent wave on LPom modes.

A transverse flow excimer laser produces an output power of 10 W at 308nm. The gas reeireulating system and the dosage distribution of X-ray preionization are described, and the effects of gas flow velocity on the laser output are rediscussed.

In this paper characteristics of field pattern distribution by laser hardening and the important parameters are presented. Through analysis on multi-factor tests, the optimum parameters are determined. Test of cutting performance shows that its lifetime can be incre-ased greatly.

According to the halftone principle, a screen is introduced which is composed of Ronchi gratings by means of theta modulation. The screen can be used to encode a picture with continuous gray tones. The encoded picture can be demodulated by a spatial filtering system with a polychromatic source. A picture with pseudocolor of equidensity can be gained.The screen can be made easily and developed into multi-density slices.

Polyeystalline InP films are deposited on SiO2 insulating substrate using a conventional EF sputtering equipment. The experimental results show a significant increase in grain size after Ar+ laser irradiation. Analysis of the stoichiometrical rate of InP by Rutherford backscattering spectrometry shows that the decomposition of InP is greatly suppressed by using a SiO2 encapsulant. Theoretical discussion on the recrystallization mechanism under Ar+ laser irradiation is presented.

Receiving surface uniformity of 80 mm aperture bulk absorption glass calorimeters have been measured and studied. The uniformity can be improved by suitably choosing materials thickness of receiver disk and distribution of semiconductor thermoelectric modules. The uniformity error is within ±2.1%.

This paper reports a new and useful optical component-a cylinder converterwith two convex circular cones. It can poavert circular profile of a laser beam into a ring one with given sizes. The principle, structure and choice of parameters are described. Some applications of laser beams with ring profiles are given.

In the experiment of interaction between laser light and target materials, the luminescence, temperature, the counter action of resultant products on laser light, and the temporal and spatial resolution have been measured.

Problems concerning the theory of equivalent conf ocal resonators are investigated. It is worth considering the strictness of building up mode theory with the equivalent oonf ocal resonator method.

In this paper, the mode-locking of pentamathylidyne dissolved in various solvents were studied and their averagepulse duration was measured. The mode-locked pulse trains using pentamethylidyne, undeeamethylidyne and BDN as the saturable absorbers were observed ona 600 MHz oscilloscope respectively, and their mode-locked quality and stability were compared.

We have measured the velocity spread of the e-beam of our Raman free-electron laser by considering the Larmor motion of electrons in a finite guiding magnetic field. Measurement shows that the axial velocity spread is 0.1%, satisfying the criteria for collective effects to dominate.

Reported here are clinical results of 89 cases of oral mucoceles treated byNd: YAG laser with satisfactory effect.