Physical mechanisms of increasing output. power of pulsed dye laser by inserting an intracavity lens are studied. The theoretical analysis is in agreenient with experimental results.

Continnously shortenirig of backward pulse duration can be achieved by changing the relative delay time of three incident pulses is predicted theoretically and verified experimentally. Some factors affecting the experiment have been analysed and’discussed.

UV preionization of pure He, Ng; Ar, NV and CO2 laser gas mixture were studied, by means. of a modified coaxial probe as positive probe. The experimental result shows that the photoelectron densities are increased by adding- moderate amqunts of tripropylanmine ia CO2 laser gas mixture.

The results in, [6] and nondegenerate two photon CW laser oscillation, process by means of the stationary state solution of reduced, optical Bloch equation is discussed. The formulas on gain, saturation, dispersion and frequency pulling of the laser material are obtained. The results are compared with, those of the monomode two-photon lasers. The effect of coupling between the two modes on the character is analysed.

A quantum theory for collective spontaneous emission of a multiatomic system with different resonance frequencies is, applied here to the superradiant emission of two groups of atoms undergoing two independent transitions. An analytical expression for the emmited intensity as a function of time is obtained after making rotating wave approximation, slowly varying envelope approximation and decorrelation approximation.

Gaussian beams can be judged and measured using a new method described here which measures only the intensities on four coordinate points in the same cross section of the measured beam.

This paper puts foward a proposal for auto-orientation of a KDP crystal array and describes a microprocessor auto-orientation system which can auto-regulate the single piece of KDP crystal to its optimal matching direction. The control accuracy of the system E= +16.3. s. The system is able to track the change of the matching angle in real-time. It is able to compensate the influence of temperature drift and external vibration on the orientation.

A mathematical description for considering a speckle gram as superposition of random gratings is proposed, wholefield speckle analysis by moire theory is treated, and a fringe formula which conforms to physical process is obtained. The relation between fringe visibility tested piece deformation and filtering aperture as well as the properties of secondary speckle are discussed.

Some spectral experiments using a high repetition rate and tunable dye laser as optical source are given. Ne impacfc-indtieed fluorescence spectra by irradiation of pulsed dye laser, the time-integral spectra of pulse optogalvanic signals of Ne-Cu lamps and taa optogalvsnic spectra in Kr+U HCD are obtained.

Semiconductor materials such as Ge and InP etc, were investigated by the laser-induced chemical photolithography with argon ion laser. Two kinds of thresholds of light intensities were observrd respectively for the scanning photolithography on the surface and the rapid penetrated etching. The former has a lower threshold and the latter higher depending on the matting point. There exists a complicated relation between the etching rate and the light intensity. The etching rate decreased with the increase of the etching depth. Semiconductor species with higher dopant concentration were etched faster than those with lower dopant concentration.

Measurement’ of electron temperature of laser plasma by means of K-edge filter detectors is reported. The results show that for broadband and narrowband laser irradiation the thermal electron temperature at the range of 420-500eV are quite similar, but the hot electron temperatures from 2.5 to 4.0 keV are different. The hot electron temperature for broadband laser irradiation is lower than that for narrowband lager irradiation.

Variation of radial profiles of optogalvanie signals with the current, temperature and pressure in a CO2-discharged positive column has been investigated. An equation of the CO2 radial OGS is given, the radial distributions of electros density in CO2 positive column have been calculated. It was found that the distribution of electron density was converged to the axis of the column with rising pressure and current. The experimentel results are in agreement with the theory on gas dischkrge.

The behavior of solitons propagating in ideal monomode fiber is described by nonlinear Schodihger equation. By meatos of inverse scattering method the exact solution of soliton at N=3, 4, 5 is presented and their law of propagation is also given.

This paper describes a set-up for static teat, of erasable phase transition disc mate-rials. It has a power density of more than 8mW/um2, light spot of 1um and variable exposuretime of 0.1 μs to 1 ms

In this paper we present theoretical analysis and experiments on the optical first-order and second-order differentiation operation of cosine objects. Experimental results are in agreement with theories.

Alloying of the -sample sxtrface of 45# steel and high phosphorus cast iron witha high-power CW CO2 laser have been studied. Our analysis shows that a uniformly dendriticstructure is exhibited for the sample sufcfaces of 45 steel and a finer ledeburite mierostructurefor high phosphorus cast iron. The sample surfaces have a higher nickl content after laseralloying.

The mechanism and experimental method for laser enhanced plating are described. With this new technique we got spots and lines of copper plated on glass substrates-. A plating rate of 0.1-lum/s and plating enhancement ratio on the order of 103 have been obtained.

Laser pulse width can be narrowed and pulse number and the interval can be controlled with disc-rotor modulation. Laser drilling by disc-rotor modulation can further improve the accuracy, surface finishing and stability.