A general review is made on the past and the future of the research progress of laser isotope separation in China. Enrichment experiments on such isotopes as D, T, Li, B, C, S, U have been conducted successfully, valuable progress on the theoretical aspect has also been made.

Using ray-matrix method we investigated the resonators containing two kinds of apertures. For the first one with soft-aperture, a general analysis solution of eigenmodes was derived on the basis of the diffraction integral equation. The relationship between the features of the zero-order mode and size and position of the aperture was investigated. For the second one with hard-aperture, we substituted a Gaussian aperture with suitable diameter for the used aperture, the approximate solution of eigenmode was obtained. The result was used for analysing the mode-selecting resonator with iris, the self-aperture mode-selecting resonator and thermo-insensitive resonator containing a aperture. The theory has been well verified by our experiments.

A discharge model on the sputtering hollow cathode discharge(SHCD)copper ion laser is established, its characteristics of discharge, sputtering and the particle interaction processes are analysed. The model has been verified experimentally.

This paper describes a fast-flow open-cycle CO2 laser utilizing He-free mixture. The maximum output power was 1400W, with an electro-optic efficiency of～5%. A molecular kinetic model under the flow condition was used to calculate the distribution of small-signal gain along the gas flow direction.

We observed that natural orientation of polarization can be changed by exerting an external mechanical pressure on the mirror, and a large mechanical pressure can change the orthogonal polarization directions of several longitudinal modes into the same polarization direction, thus we can obtain a new type of intra-cavity He-Ne laser with polarized output.

The photodegradation mechanism in coumarin laser dye solutions is investigated at 77K by the direct detection of free radicals using ESR technique and of products using spectrometric identification after degradation under UV flashes. As a result, the following degradation mechanism is proposed: the energy is transferred from a dye molucule（T1）to an O2 molecule. The excited O2 molecule oxidizes a free radical in the solvent. The dye of degradation is caused mainly by O2 oxidation.

From both rubidium and its trace impurity cesium the optically pumped stimulated radiation is obtained. The observed spectra are analyzed, and their related mechanism is discussed. The possibility of the stimulated radiation at the low atomic density is demonstrated, and the possibility of impurity examination by means of stimulated radiation signals is estimated.

The amplified spontaneous emission in dye solutions excited with powerpul picosecond light pulses is studied in two respects:1. spectral peak shift and the emission width;2. physical mechamism for producing a periodic fine structure in the emission spectrum.

In this paper the reflection behaviour of transmission holograms is discussed more comprehensively thanin the literature available on this subject.

Effects of a uniform magnetic field superposing a space-period magnetic field on the gain of the free-electron laser were analysed and calculations were carried out. It is shown that the gain is increased by orders of magnitude when a suitable period length and uniform magnetic field strength are chosen, whereas the gain will be reduced by superposing the uniform field when disappropriate conditions are chosen. The right operating conditions and calculation results are given.

First we irradiated respectively RNA extracted from cancer cells with laser light at different wavelengths and energy then preheated the cancer cells RNA for 18 hrs and transplanted them into the absominal cavity of C57 DL mice, and observed the influence of carcinoma growth. Result: Ⅰ3250A and 4416A group: no ascitic cancer for six months. Ⅱ.3371A group: ascitic cancer at some parts from the 21th day. Ⅲ.4880A～5145A-group: ascitic cancer caused in all mice from 50 th day, and a part engendered with abdominal cavity consolidatic cancer.

Potential damage factors are analysed in laser systems from the frequent laser eye damage accidents in recent years. Hygienic physics experiments were performed on“reflected laser light from the hitting spots”which causes most eye disasters, and measures for eye pro-tection against laser damage are discussed.

A RF excited CW CO2 waveguide laser has been developed, and effective match between the laser head and the RF power supply achieved. The exciting frequency was 35.8 MHz The discharge channel size was 2mm×2mm×150mm. The power output of up to 2.8 W and the efficiency of up to 4.8% have been obtained at a total pressure of 130 Torr with gas mixture ratio of CO2: N2: He: Xe=1:0.3:4.2:0.2.

In this paper, the influence of lasing on the electron energy distribution in CO2 lasers is studied by means of the second derivative of the probe current. It has been shown that the influence of lasing appears around 2.5eV.

The effect of H2 on the X-ray preionized long pulse XeCl excimer laser was studied experimentally. The peak intensity of laser output can be increased by more than 30% by adding small amount of H2 to the XeCl laser gas mixture.

Using optogalvanic spectroscopy we observed the correlation phenomena of the vibration-rotational transitions in the CO discharge medium.

This paper reports a new principle and method for the suppression of laser noise, it is the principle of decreasing laser noise by mutual exclusion and the method of non-even particular cylindrical surface charge. The effect of suppressing laser noise by using the principle was tested.

This paper presents a new method to display laser modes from the laser patterns, and its characteristics are discussed.

In this paper the lon plating technique used to make high reflectivity gold film is presented, and the experimenmal results of the film adherrence and the laser radiation for this perpose are described.

The electrical calibration technique for 80mm aperture absobing glass volume calorimeter is discussed. It is shown that the absolute value for calibration accuracy is within 2%.