We have developed high power atomic iodine laser amplif er with an aperture of 320 mm and length of 1.4m. Its conversion efficiency reaches to 0.8%. The cross section of the amplif er is better than 4%. The diffraction index change during the pumpimg period is less than 2x 10-7. Experimental results show that the empirical formula D P=20000(Pa.cm), in which P is the pressure of active material C3F7I inside the laser tube and D the diameter of an amplifer, is suitable for choosing parameters of amplifera.

Considering the condition of charged particle self-field the gain of FEL is studied and compared to the results obtained by neglecting the self-field. It is shown that self-field has some effects on the gain of the FEL’s.

This paper presents the pulsed laser eharateristics of laser NAB crystals grown in our institute. The maximum laser outpu t of a NAB rod with dimensions of 3. 2mm X 23. 7mm was 422mJ a pulse when it was pumped with a single xenon flashlamp. The laser threshold of a NAB crystal rod with dimensions of 1.8mmX 2.4mm was determined to be 67mJ. By using BDN dye for switching, the laser pulse width of a NAB rod with dimensions of 1.8minx8.4 mm was 8ns. The output laser beam was linearly polarized with beam divergence angle of about 2mrad and wavelength of A=1.063 μm.

The influences of the thermal radiation, field zero-point fluctuation and spontaneous emission on the AM and FM noise in a semiconductor laser are studied theoretically.

Phase matching for harmonics and frequency mixing by intensity-dependent refraction index e_ffcts is presented, in this way phase-matched third harmonic generation in Ba vapor has been realized for the first time.

A novel filter for correlation is presented which; behaves as intensity correlatpr along with other elements and has the common advantages of intensity correlators.This lensless intensity correlation system is simple and easy to operate and decreases the requirement of resetting precision for the filter.

Investigation of the phase change on Fourier transform plane caused by a moving object shows that it is possible to measure a 3-D displacement vector using comparison of the phase-change recorded on a double exposure hologram. Based on it, a novel approach for measuring a 3-D displacement vector is described here. Theoretical analysis shows that the problems usually appeare during interpreting the interferograms of a conventional double exposure hologram for 3-D, displacement measurement have been effectively avoided. Experimental results are well coincident with theoretical analysis. Quantitative calculation method ia also presented.

By means of GILD(gas immersion laser doping)on the surfaces of n-Si samples with BBra vapor as material, Si-photo-cells doped with boron have been manufactured with the maximum doping concentration of 1.2x 1021 B+/cm3 near the surface, the junction depth of 0.08/am at 1017 B+/cms and the conversion efficiency of about 9.5% without antireflection coatings.

Laser cladding of FeCrSiB alloy coatings on A3 steel plate has been performed with a 5kW CcO2 laser. The microstrueture and performance have been significantly improved. Laser cladding casing consist of a’-Fe+y-Fe+M23O6+M7C3+Fe2B. Excellent performances of surface alloy have been, obtained on low priced steel plate. It is shown that laser cladding ia via-ble for controllably modified aiaterialS aurface.

A calculating procedure for optical correction of LDA measurement of cylindrical tube flow is presented. The calculated deviation error is less than 1.86 x10-11 in the ideal case of the tube filled with liquids having the same refractive index as the tube wall. This method can also be used to predict the position limit of the measured points.

Measuring the variation of the output" power of a waveguide CO2 laser with coupling distance for different curvatures of the cavity mirror, a minimal coupling loss point is obtained. Experimental results show that the frequency tuning range can thus be increased.

By meana of experiment and simple theory; we investigated the output’ power of the tunable dye laser pumped by a Cu vapor laser with planar and concave mirrors used as the front mirror of the dye laser respectively. The experimental result shovs that for the same oscillator length there is a higher output pbwer for the concave one than that for the planar one, which agrees with our theory.

Following Langevin rate equations, the expressions of phase noise power spectrum density are obtained and the results in good agreement with experiment and calculations are given.

A segment of fiber was coupled to a GaAlAs DH laser as external cavity, and L-I characteristics and spectra of the laser with and without fiber coupled were measured.Mode selection in the laser with coupled fiber were observed.

The thermal stability of a nonresonant ring laser cavity is analyzed by mans of equivalent laser resonantors. In the general case i. e., principal-point distances hi(i=1, 2) varies with the focal length of the internal thermal lens, the analytical expressions are derived and compared with those obtained by using approximate method.

Experimental procedures are presented for laser alloying of 60# steel surface using a transversely excited flow CW CO2 laser with an output power of about 2 kW. Microstructural and electron spectrum analyses of the treated surface indicate that laser alloying offers the possibility in situ alloy synthesis on workpiece surface.