The Ronchi grating bearing 180°-shifting phase is used, in this paper, as a Hilbert transform filter. Some experimental results are presented and the optical characteristics of this kind of laser schlieren instrument are analyzed.

The properties of the pseudo-phase-conjugate array-the optical transfer matrix of the optical elements of the array, the resolution of the array and the machanism of the compensation for distortions caused by a large volume of distortion medium are analyzed by using diffraction theory.

The effect on noise performance of a white-light optical signal processor under temporally partial coherent illumination is presented. The output signal-to-noise ratio (SNE) is evaluated through the well-known partial coherence theory. This output SNE is used as a means of measurement for the noise performance of the proposed white-light processing system. The sources of noise considered are the grain-noise and the phase-noise at the input and Fourier plane. Except For the grain-noise at the input plane, we show that the output SNR can be improved considerably by using a broadband temporally partial coherent illnminatioii.

A negatic ion model of X-ray perionization kinetics is given for a discharge pumped XeCl laser. It is found that the perionization conditions are related to the concentration of the gas mixtures. The result shows that the model is in good agreement with our recent experiments.

Experimental results of a triatomic noble gas halide excimer Kr2F laser pumped by an electron beam are reported. Such a lager has been operated using high pressure mixtures composed of optimized ratios of Ar (or Ne, Kr, and He), Kr, and NF3 (or F2), and N2. Furthermore, the effect of gas temperature upon the Kr2F* emission characteristics was investigated.

The defects of alexandrite crystal (BeAl2O4: Cr) grown by Chochralski technique were investigated by chemical etching, optical microscopy, X-ray diffraction topography and electron microprobe analysis. The results obtained are summarized as follows: (1) Eolicdle dislocation etchants were restablished on the (1 0 0), (0 1 0) and (0 0 1) surfaces. (2) The distributions of dislocations in crystals are nonuniform. There are two sources for the dislocation production. One is seed and other is inclusions. Most of the dislocations are edge ones, their Burger's vectors are in direction and glide planes are (0 1 0). (3) The main inclusions such as bubbles, tunnels and secondary phase pricipitate particles often appear in grown crystals, which are caused by impurities in raw material and constitutional supercooling during growth.

In this paper a definition of static stability is given and the output power stability of optical bistable devices in the condition of steady operation is discussed. It is pointed out that the multi-beam interference device is better than the two-beam one in static stability and the nonlinear, especially the exponential feedback system is better than the linear one. A laser power stabilizer has been fabricated for the first time by authors using a polarization interference OBD with exponential feedback and a high static stability near 50 haa been obtained. The experimental results are consistent with, the calculated values.

Mercury is irradiated by ruby laser at 694.3 nm. A now spectral line of 288.22 nm is observed at far UV wave length range. The transition is caused by six photon absorption.

Two schemes of compensation for phase distortions in the laser amplifier have been proposed and experimentally demonstrated by using degenerate four-wave mixing. In the first scheme, BDN dye solution in diohloride ethane was used as the nonlinear medium, the saturable absorber was put outside of the laser ocillator. Using polarization discrimination, phase compensated output was coupled from Nd:YAG laser system. The backward wave output amplified about four times was experimentally obtained. In the other soheme, a phase conjugate mirror was put inside the oscillator cavity. The BDN dye solution was used as the degenerate four-wave mixing and the Q-switohing medium as well. Q-switehed output compensated for phase distoriiions in the amplifier wag obtained. The property of compensating for phase distortions was investigated. The laser output as a function of the conoentration of BDN dye solution was measured.

Optical activity and Faraday effect in bismuth germanium oxide (Bi12GeO20) were investigated in the spectral region 430.0-800.0 nm. It was found that the best fitted model of optical activity in Bi12GeO20 to the experimental results was the Drude model of molecule coupled oscillators. However the relation of optical activity with the crystal structure is not clear yet. Due to the quite strong Faraday effect, Bi12GeO20 could possibly be applied to some optical nonreciprocal or polarization devices.

With Si(Li) X-ray energy spectrometer, the intensity of low-energy radioactive source 55Pe has been measured and the absolute characteristic curves of emulsion for 5F medical film and Kodak No-screen film under the condition of 55Fe radiation have also been obtained using time-mark exposure technique. When the optical density D of 5F film is equal to 1, then the corresponding exposure H is equal to 12 × 107 photo/cm2.

We have measured the resonant ionization spectrum of alkali-metal potassium vapor in the range of 5780 A - 5920 A, using a flashlamp pumped tunable dye laser. The results show that the two-photon transitions of atomic potassium 4s-ns (n=12-18), 4s-nd(n=10-16) and stronger atomic potassium 4p-7s, 4p-5d transitions have been obtained. These ionization signals of 4p-7s, 4p-5d transitions are produced from potassium dimer-potassium atom hybrid two-photo transitions. We have discussed the results.

A method for determining the refractive index, thickness and extinction coefficient of optical films from measured ellipsometric ψ and Δ is described. This method is founded more convergent and time-saving parameters.

In this paper, we describe a new electro-optical compensated automatic ellipsome-ter. The design principles are discussed in detail and the measurement results on SiO2 film are given. A new type of automatic spectrum-ellipsometer may be developed based on it.