The characteristics of laser dye DCM, such as tuning range and peak wavelength in different solvents and at several concentrations have been studied experimentally in detail. The conversion efficiency of DCM with nitrogen laser excitation is as high as that of Rhodamine 6G.

A number of substituted 7-amino coumarins C311, C47, C102, C152, C481 have been synthesized. Their spectral and lasing behaviour has heen measured. The data obtained in our experiments show that substituted 7-amino coumarins have the advantages of high efficiency, broad tunable band, and high chemical stability. The effects of the substitution on the behaviour has aJso been discussed.

Drdinary image-plane holography requires the reconstructed image to straddle over the hologram, thus the image in front of the hologram causes visual confusion.This paper describes our experiments using non-paraxial astigmatism theory to make the white-light reconstructed image on the image-plane holography appear behind the hologram, thus avoiding visual confusion. All conditions for the experiments and the results are given in detail. Using this method, we have obtained a clear, bright, speckle-less white-light reconstructed stereoscopic image, located behind the hologram.

This paper reports the experimental investigations on the discharge noise for He-Ne lasers. A lot of noise phenomena have been observed within the range of 0-300 khz by changing the tube structure, gas pressure and discharge current of the laser. The relation between noise and moving striation is also discussed. Finally, some methods for lowering the discharge noise are suggested.

The experimental dependence of isotopieally selective dissociation of BCl3 on the laser frequency, energy of each pulse and pulse number are investigated. The maximum dissociation rate of BCl3 molecules is found to be shifted by 21cm-1 relative to its linear absorption spectrum in the direction of longer wavelength. The enrichment coefficient of 11BCl3 is 5.8.

Optical waveguides fabricated by immersing glass into molten AgNO3 is reported. It is simple, easy and reproducible. The effective refractive index, thickness and loss of the optical waveguide were measured and the optical loss is less than 1db/cm.

Tuning characteristics of a pulsed dye laser forced oscillator are studied. Several experimental phenomena are explained by the third order mode-coupled equation deduced for dye lasers. The tuning method and the experimental results are also given.

The formulas for strain quantity and fringe spacing on the basis of Bragg equation are derived. The relationship between fringe deformation and internal flaws is analysed.

The addition and subtraction of characters can be performed in a coherent optical processing system if a grating is used as a filter. In this paper, we describe the addition and subtraction of characters by a sinusodal grating and a Bonchi grating. We compared the intensities of the first order image after addition by sinusoidal grating with that by Eonchi grating.

In this paper, we use the model for turbulence intensity distribution in Shanghai to analyse the space correlation of atmospheric scintillation. Some characteristics of atmospheric scintillation under the condition of nonhomogeneous turbulence are quite different from those deduced from homogeneous condition. The space correlation and the correlative scale of scintillation of laser beam on long path are discussed and some characteristics of those on short paths are discussed too.

A brief introduction is given to the exhibition of lasers and spectroscopic instruments sponsored by the Department of Technological Sciences, Academia Sinica in Beijing, and some exhibits on display are introduced.

Improvements are described of electro-optic Q-switching and automatic ignition circuits for simmering pulsed xenon lamps of solid state laser power supply. It enables the automatization of these circuits, and results in simple structure, remarkable improvement of performances, reduction of cost and easy operation.

A simple and useful method for determining polarized performance of CO2 laser is described. It is convenient to use this method to determine both polarizability and direction of polarized plane of laser light simultaneously. Experimental apparatus, operational procedure and experimental results have been presented.

Characteristics of frequency stabilization for CO2 laser are studied using two methods: free running and SF6 saturation absorption. Frequency stability of better than 2×10-10 has been obtained.

Taking advantage of relaxation of an AlxGa1-xAs DH laser, light pulses of 300 ps have been obtained by driving laser with pulsed current of 500 ps duration.

A device has been developed in which an electron gun is used to control the main discharge of two CO2 lasers. It operates normally on 2~3 spectral branches without dispersion element and is tunable within four spectral bands as a grating is employed arid the output energy can be up to 10 j/pulse atm.

In this experiment frequency doubling of Nd: YAG laser was made with CD*A crystal. Compared with ADP, KDP, KD*P and LI crystals, the efficiency of CD*A is the highest. We think CD*A crystal is an excellent material for frequency doubling of high power neodymium lasers.

The experimental method and results of He-Ne laser with frequency stabilized to saturated absorption of Neon atom within the cavity are described. Two channel stabilized electronics were adopted. The stability and the repeatability are 3x10-10 and 1x10-8 respectively. The vacuum wavelengths of two neon stabilized lasers are given.

The paper describes an alignment device used for intracavity laser tubes. Experiments show that satisfactory alignment of cavity can be obtained with an external magnetic field to adjust the position of the discharge tube and the glow discharge channels.

Some preliminary results are described of the laser breeding effects on seed weight.

The paper reports a nondestructive technique to measure the ratio of inside diameter to outside diameter of the quartz tube based on the principles of geometrical optics. This technique has also been extended to measure the thickness of the deposit in CVD or MCVD method.

A review is given on the wide applications of Nd doped silicata glasses in laser science and technology in China.