This article is intended as a review of the development of optical fiber communications in China.

On the basis of light interaction with two-level atomic system, we derive the interaction solitary wave equations, its solution and two necessary conditions for the existence of the solution.

A simplified model for calculating concentration field of diffusion-type CW HP chemical lasers is presented. The velocity field is assumed to be analogical to one of the ordinary flat-plate laminar boundarys. The temperature field and concentration field are solved by coupling the energy and species conservation equations as well as the velocity similar solution. A contour of the mixing boundary is obtained. In addition, the effects of velocity, temperature of the gas flow and chemical reactions on HF concentration of the excited states are studied.

This paper discusses the influences of the refractive index change resulting from gas heating in the transverse-flow electrical discharge COa laser on the optical axis and the transverse mode. The calculation indicates that tho first order quantity of the refractive index change will vary the position and tho angle of the laser axis. Tho second order quantity of tho refractive index change is analogous to the negative lens effect in the axisymmetrical discharge tube1. Both effects will be enhanced with the increase of injection power and the mixture pressure, especially with the gain length.

An ezeimer laser pumped ps dye amplifier system is described, in which the signal passes for three times during one pumping duration. Using efficiently the pumping energy, this amplifier exhibits a high gain of 4×104, low pulse ASE of less than 1% and no pulse broadening. It is simple in structure and stable in operation. Computer simulation gives satisfactory agreement with the experimental results.

In this paper a widely tunable dye laser with picosecond pulse duration is described. The tunable range is about 450 A with only one dye solution.

In this paper, the experimental fabrication of a GaAs-Al0.3Ga0.7As DH lasor with two-sections in a common cavity is reported. The stable output and transient output characteristics of the laser were measured.

Operating characteristics of a repetitive excimer laser without gas cycling system are reported. 70 mJ per a pulse at the pulse repetition frequency of 5 Hz and a lifetime of 105 shots are obtained.

We present in this report an experimental study of the mode structure of the hollow-cathode He-Cd+ laser and a measurement of the profile of spontaneous emission of the laser transition at 5378 A. The experiments show that the laser can operate in a single-longitudinal-mode without optical mode-selection. The output characteristics of the laser is analysed.

The absorption and fluorescence measurements of the titanuim doped fluoropho-sphate glasses have been performed. The visible luminescence of titanium excited at the U V range has been observed. It is found that there are an asymmetrical absorption band at 529 nm and a shoulder at 685 nm in the absorption spectrum. The authors believe that the UV absorption with high intensity belongs to the charge transfer transition of Ti4+ and Ti3+ ions.

The design and experimental results of a constant temperature head for semiconductor laser diodesare reported. Its temperature stability is estimated to be ±2×10-3℃.

The F-colour centers in γ-irradiated alkali halide crystals (KC1, NaCl, KBr, LiF) were investigated by ESR. method. The width of rasonant spectral lines was calculated, which agrees with the experimental results. And the origin of the deviations between the thero-retical results and the experimental ones are discussed.

The laser characteristics of flashlamp pumped DCM dye are experimentally investigated. The laser pulse width, tuning range and laser efficiency of DCM are given. Under the flashlamp excitation, the ethanal solution of DCM is safer and more convenient, and the laser efficiency is higher.

The animal experiments suggest that small white mice with sarcoma and liver cancer, in which HPD and fluorescein sodium are injected into the abdominal cavities, can produce intenser fluorescence in the tumors than in the normal tissues when they are irradiated by a He-Cd laser, and various types of lights have different effects on the small white mice injected with HPD: sunlight has the greatest effect, then the 100 W electric light, and HPD has some side-effects on the livers of small white mice.

Twenty rabbits were used to explore the wound coagulation by local irradiation of He-Ne laser. The result observed showed that the average coagulation time in the experimental group was obviously shorter than that of the control group, and the irradiating time to the wound had a significant effect of accelerating wound coagulation.

This paper reports that the He-Ne laser has the effect of healing the skin. He-Ne laser irradiation not only has the effect on the irradiated areas, but also the immuna capability of the body.