In this paper, a method for real-time measurement of power density distrirbution of continuous high power infrared lasers on the basis of researches in references [1,2] is introduceds. Using this method, we can cauyont measurement in a state of working of the laser device and raise measurement precision, gaining satisfactory result in the measurement even without making compensation operation to the diffraction effect.

Several high quality crystals of AgGaSe2 have been grown utilizing the vertical Bridgman technique. Boule sizes were typically 20 mm in diameter and 80 mm long. The optical transmission of AgGaSe2 samples annealed in the presence of Ag2Se3 is essentially reflection-limited over most of its transmission ranges. Calculations were made of the angular tuning characteristics of infrared frequency doublers using type Ⅰ and type Ⅱ processes. The frequency doublers of 10. 6 μm radiation for type Ⅰ phase matching were built from these crystals. The phase matching angle measured experimentally is 56.1°, and the acceptance angle parameter ΔΘ·L is 1.04°·cm in a frequency doubling experiment of the 10.6 μm radiation from a TEA CO2 laser.

Amorphous laser-cladding of PdCuSi alloy on a copper substrate was Studied using both a CW 5 kW CO2 laser and a 200 W pulsed Nd: YAG laser with the help of pre-plated Ni-P amorphous plating. X-ray diffraction experiment showed that an amorphous layer of more than 20 μm containing a little of Pd4Si and Pd5Si phases was formed. The Ni-P plating seemed to play a role in resistance to the effect of the copper substrate on component dilution and solidification process of the PdCuSi alloy. This study implied an interesting way of making amorphous Pd-alloy based electrical contact elements by laser cladding.

Hypereutectic Al- 18Si alloy is remelted and solidified rapidly with a 2 kW CO2 CW laser under different power densities and scanning velocities. The microstructures in the treated zone are analysed with SEM and an electron microprobe analyser. From the analysis of experimental results and the coupled zone computed for the f-n f system of Al-Si alloy with a nonequilibrium theory, it is shown that if the conditions of solidification determined by power density and scanning velocity are established in the central part of the coupled zone, a full eutectic structure with an eutectic spacing below 200 nm can be obtained using laser surface treatment for hypereutectic Al-Si alloy.

Pancreas with duodenum was transplanted from healthy, male rats to the artificially diseased male rats of alloxan diabetes. He- Ne laser irradiation, immune inhibitors and their combination were applied immediately after the operation to observe their effects against rejection. The results are as follows: with the treatment of He-Ne laser irradiation at a dose of 39. 72 J/cm2, the starting time of rejection to the organs was delayed, the living time of the organs was prolonged and the intensity of rejection was lightened. The above stated effects can be stronger when laser irradiation is combined with medication of azathioprin (at the dose of 8-5-3 mg/kg/day) and the effects are colse to those of cydosporin A(CsA).

Numerical fitting reveals that the transmitting function of the filter used in this work can be described by the product of a Lorentzian function and the standard transmitting function of the filter. Using this filter as the tuning element of an external cavity semiconductor laser, a tuning range of ～20 nm from 1272.5 nm to 1291.7nm has been achieved.

A sulfur vapor cell was transversely pumped by a 308 nm XeCl excimer laser. The laser oscillations associated with six spectrum bands of S2 B-X transition in the near ultraviolet region (330.9～390.0 nm) were realized and the laser parameters weremeasured.

A Ti: sapphire laser two-direction pumped by the second harmonic of a Nd: YAG laser is reported. A pulsed energy of 88 mJ, a conversion efficiency of 38. 5% and a linewidth of 0. 003 nm have been obtained.

A high power copper vapor laser is reported. Its maximum output power is 62 W with an efficiency of 1. 0%. Performances of the device are measured and discussed.

In this paper, the transmission characteristics of a Gaussian beam in a thermal lensing resonator with a VRM output coupler are analyzed. The output coupling and mode discrimination role of the VRM are studied. Experimental results accord with the theoretical analysis. From a high power continuous wave solid state laser with a VRM output coupler a laser beam with output power of 180 W and the beam parameter product of 6.25 mm.mrad are abtained.

The electric field component of LP01 mode at the end of a monomode fiber is expanded into a superposition of Gauss- Laguerre series in terms of the function approximation method. The butted loss has been calculated when the distance between the fiber end and the mirror is L. The butted loss measured in the experiemts has thus been explained.

Adopting an oscillator-amplifier copper vapor laser system with a self-filtering unstable resonator, we obtained laser output of 8. 8 W at 510. 6 nm with near diffractionlimited divergence and polarization degree of 97 %. Meantime, we compared two oscillatoramplifier systems containing a self-filtering unstable resonator and a negative branch unstable resonator, respectively.

CO2 laser microwave excitation through a waveguide coupled cavity is presented. It has the characteristics of simple structure and low discharge break-down power, and is easy to realize frequency tuning and impedence matching. The cavity design principles are described through its low frequency equivalant circuit. The experimental results of gas discharge are given.

An acousto-optic Q-switched CO2 laser with a quasi-waveguide cavity has been developed. The maximum peak powers of the laser of 1.1 kW and 2.05 kW have been obtained for the cavity lengths of 515 mm and 700 mm respectively. The minimum pulse width was 100 ns, and the pulse repitition rate was 0～300 kHz. The calculated results of rate equations of the laser were approximately consistent with the experimental values.

The preionization near anode was suggestted in stead of preionization near cathode and experiments show that preionization near anode has improved both discharge homogenity and pulse energy output.

In this paper, a method of producing Si-cup by using Si anisotropic etching technique combined with an argon laser is discussed. We have used a focused laser beam to perform the localized etching on the Si. The results from the experiment show that laser irradiation can enhance etching removal rates of Si in KOH. An averaged instantaneous etching rate as high as 21 μm/min has been observed in silicon for a 3 W input laser power. The chemical etching rates dependence on the laser power and on the temperature are further studied.

We have developed and successfully demonstrated a “point projection absorption spectroscopy (PPAS)” technique to record keV absorption spectra in the coronal region of laser produced germanium plasmas and aluminium plasmas which provide spatial information in the coma at a ～24 μm level resolution and can freeze the motion of the expanding plasmas at a≈250 ps level.

The growth of NaCl: OH- crystals and formation of (F2+)H centers are reported in this paper. The (F2+)H center densities of the crystals are as high as those of French crystals and the non-active losses of our crystals at 1. 5 μm are as low as the French products.

The powder and single crystal of Na5Er (WO4)4 have been prepared and their lattice parameters, absorption, excitation and fluorescence spectra have been measured. Meanwhile, the oscillator strength has been calculated from the absorption spectrum. According to Judd-Ofelt theory the spectral strength parameters Ω2=1. 74×10-20 cm2, Ω4 = 1. 46 × 10-20 cm2, Ω6 = 0. 51× 10-20 cm2 of Er3+ have been fitted. Then the spectral parameters of Er3+ including spontaneous emission electric- dipole and magnetic-dipole oscillator strengths, transition probabilities, radiative lifetime, fluorescent branch ratio and integral emission oross-section have been calculated. Finally, the probalility of emitting laser radiation of Er3+ is discussed.