In this paper the calculating formula of the Talbot length under the condition of the light fields of converging spherical waves is given, and a new method of measuring the focal length and refractive index of a lens with Moire technique ig presented. It avoids the deficiencies of other methods proposed in the recent two years.

In this paper, we have studied theoretically the resonant Self-focusing of two-frequency laser beams in plasmas. From the plasma fluid equations, we have derived the expression of the nonlinear dieletric contants of plasmas driven by two-frequency laser beams and showed the effect of the ponderomotive force of the plasma waves. After giving the approximate solution of longitudinal electrostatic field, the characters of resonant Self-focusing are showed. Finally, the influence of resonant Self-focusing on particle aooeleration in beat wave accelerator also be discussed.

Electron density profile of the covana in a laser-produced plasma in measured by using Eaman-shifted probe with polarization interferometry. Results are obtained at several relative relay times of cylindrical and microsphere targets.

The first observation of the 3S-4S stimulated electronic Raman scattering (SEES) in sodium vapor with the infrared output tunable from 2.38μm to 2.65μm is reported. The calculation for the power gain factors and the measurment for the infrared output as a function of a dye laser tunning are made and both results are in good agreement. The pumping threshold in dependence of sodium vapor pressures are measured. The photon-conversion efficiency is about 30%. Simultaneously, the amplified spontaneous emission (ASE) on the Na 4S-3P transition is aleo observed.

By employing the semiolassioal theory of lasers, relations between mode number and laser parameters are described. These parameters include the relative population difference, the line-width and line-shape of the transmission of intracavity tuning elements, and the difference between self-saturation and cross-saturation coefficients, etc. A detailed physical analysis based on mode competition theory is given.

The Strehl Definition (S. D.) is one of commonly used criterion for evaluating the quality of an optical system, especially, for the mircosoopic objectives. In this paper several problems, which play important role in S.D. calculations, are considered in detail. Namely, the defoous, the expansion formula of the wave aberrations of the deoenteral system as well as the numerical calculation method. The proposed method can also be used for estimating the quality of the decenteral optical systems.

The scanning etching on Si, GaAs and Zn plates with a frequency doubling Ar+ laser at 257.3 nm is reported. The width of the smallest etched line 1.2μm was obtained. The dependence of the etching depth on the light intensity/scanning rate is given. The diffusion coefficient, free path of the halogen radical and scale of laser focused spot were estimated for the first time by the method of the laser etching technique. A threshold phenomena was observed and explained.

This paper presents a double compound dichromated gelatin holographic lenses used as a monoohromator. The spectrum halfwidth of the holographic lenses was measured and calculated. The experimental results shown the feasiblity of a new type of the monoehromator.

It is proved theoretically in this paper that the field patterns of the traveling modes in a weakly guiding optical fiber are quite similar with those of the fiber-emitted modes in the far-field region. Based on our results, far-field peak intensities of the diffraction-added lobes observed on a screen are 2-3 orders of magnitude smaller than those of mode patterns. Therefore, it is possible to determine the traveling mode in a fiber from its far-field pattern.

The ability of displaying stereograms on a computerized plotter has been applied to the 3-D reconstruction of cranial neural cells. We present in this paper the integrated digital constitutions of neural cells and the way of plotting stereo projective maps according to the stereopsis principle. The method provides a flexible and straight forward way for the study of the structures and morphology of organic cells.

The physical justification of pattern recognition with a phaseonly match filter is analysed in this paper. In the experiment the amplitude of Fourier transform of object is modified to reduce the intensity dynamic range, while phase information is preserved. The holographic match filter was made by dichromatic gelation. The high emeiency correlation is obtained by using this method.

This paper describes a deductive method of the light lock Morie fringe profile. This is more brief and pronounced concept than the method proposed by Japaneses. In comparison the theoretical calculated value with the experimental data, the results are satisfactory.

In this paper, the scanning interferometer with confocal spherical cavity structure is described, which is operated round 0.85μm and 1.3μm respectively. The free spectral range of the interferometer is 4.3GHz, and the higest resolution is 36MHz (finesse is about 120).

The possibility of using transient four-wave mixing (TFWM) in optical amplitude encoding is studied theoretically. We developed an effective numerical method to solve coupled wave equations with discontinuous solutions, and to study the influences of system parameters on the quality of signal. It has been found that the TFWM system is suitable for encoding and it can generate high data rate communication signals.

This paper reports the results of a two-laser resonance enhanced photoionization experiment of Benzene molecule. The excitation was done by two frequency doubled dye lasers. The first laser pumped the molecule to a selected singled state (S -1), from where it was ionized by a time delayed pulse of the second laser. The ion quantum yield depends on the intermediate vibronic state as well as on the wavelength of the ionizing laser. From the structure and intensity of the measured ion spectrum we derived vibrational frequencies and molecular parameters of tlie ground electronic state of the ion to a high precision. The contributions of autoionizing Bydberg Levels to the ionization cross section can dlearly be distingnislied. from direct ionization some of these resonance peaks could be assigned to vibrations within these Rydber states.

By using a cwring traveling-wave dye laser enhancement factor up to 105 of the intracavity absorption sensitivity was obtained in air even if the pump power was two times excess of threshold. Making use of singlefrequency scanning method for the first time, the resolution of. 10-2 angstrom was measured without sensitivity reduction. The experimental results agree with the predictions of modified Brunner-Paul s theory.