The Fraunhofer diffraction distribution from a blazed grating illuminated with Hermit-Gaussian beams is investigated analytically. It is found that the resolution of the grating illuminated with a Hermit-Gaussian beam is not determined by the spot size on the grating but by the parameter of the beam itself, i. e. the radius of the beam waist section.

The field distribution of laser beam after passing through the spatial filters and the foeusable power of aberrated light beam in high power lasers have been calculated using self-similar propagation modes. The intensity profile of focusing volume of aberrated light beam is given, and the calculation accuracy is 1%.

CABS technique with the broadband dye laser is described. With this technique, CARS as well as CSRS spectra can be obtained simultaneously and more than one Raman line of pyridine were recorded by each shot. The results reported show that this technique can be used to record Raman spectra of some organic molecules with nanosecond time resolution.

By using OMA-2 system (Optical Multichannel Analyzer), the spectral distribution and UV spectral effeeiency in 2200 to 8800 A region of a flash-lamp with a pulse width (FWHM) of about 3 /LIS have been measured. Only four pulses are required for making each measurement.The influence of variation of discharge voltage and the gas pressure of the flash-lamp on its spectral distribution has been investigated. The UV spectral efficiency is increased from 13% to 17% with the increasing of discharge voltage and gas pressure. The total UV emission energy also increases appreciably.

The advantages of using regular laser pulse spikes for drilling and the selection of pulse spike parameters are discussed. The regulation for ultrasonic modulation of laser pulse spikes and the influence of modulation on drilling are studied. The experiments and analyses have proved that ultrasonic modulation can improve greatly the accuracy, surface finishing and reproducibility.

This paper describes the results of ThF4 protective coating on the gold eoatedreflectors.

The changes of transmissitivy and refletivity of ion-implanted Si with time under intense CW CO2 laser irradiation have been measured. It is discovered that there is enhanced absorption of intense CO2 laser by silicon. This phenomenon may be explained qualitatively by means of free carrier absorption.

This paper reports a grating dispersion cavity used for line selection in CO lasers. Experimental comparison of this cavity with that of conventional grating shows an improvement of wavelength resolution.

Although the refractive index of the dye solutions is lower than that of the cell material, the reflectivity is high as the light beam grazes at the inner surface of the cell and the solution is of high gain, a number of low order leaky modes can be supported by the leaky waves. Furthemore, the influence of the pump light and the laser beam on the dye solution will bring about the nonuniform distribution of the refractive index of the solution, so the solution can be self-guided. Our experiments and the photos have proved the above analysis.

In this paper, we report the phase conjugate effects of multimode TEA CO2 lasers in saturable absorber SF6 and active medium CO2. The reflectivity of multimode phase conjugate wave is close to that of the longitudinal monomode.

A new graphite with high strength and low sputtering used in laser systems is reported, and a reasonable technology to increase the treatmant temperature of segmented graphite is also presented. Our test shows that the carbon black graphite can greatly prolong the life-time-of Ar+ lasers.

Alkali halide materials, with KCI in particular, have been considered as a promising candidate for high energy laser window.In order to investigate the stability of the mierostructure of hot-forged KCI, the grain boundaries were emerged by chemical etching and observed with a microscope, and incomplete recrystallization, secondary reerystallization, inhomogeneous microstructure and grain growth in polycrystal KCl were found.

This article describes the fundamental principle and experimental setup for liquid-surface ultrasonic, holography and reports the preliminary results in the application of this device to biological medical detection and NDT of industrial materials.

A number of experiments have preved that the breakdown voltage for gas laser tubes can be dropped by 50% using the modified laser tubes.

This paper presents different views on the mechanism of lowering breakdown voltage of gas laser tubes.

Misalignment sensitivity of cube corner reflector-concave mirror resonators has been derived by means of augmented 4×4 transfer mataix, and compared with that of plano-concave resonators. The former is lower than the latter in some cases.

Frequency shift of Stokes radiation for cells of various lengths were measured. Also measured were light of various intensity generated at 992 cm-1 and 3064 bm-1 for different cell lengths.

The discharge delay technique of cross-excitation in laser microspectroscopy and its main advantages are introduced.

Pulses of 12 ps in duration were generated from a passively mode-locked Nd: YAG laser using an intracavity etalon.