【摘要】 本文用不同方法研究了用于高功率激光倍频KDP晶体的质量和缺陷,用MarkⅢ型数字波面干涉仪测量了KDP晶体的光学均匀性,找到了{100}、{001}和{101}晶面的最佳化学抛光和化学腐蚀条件,用激光动态扫描超显微方法观察了KDP晶体中散射颗粒的分布和位错线,指出大部分位错线来源于籽晶。更多还原

【Abstract】 The defects in KDP crystals intended for frequency doublingcrystals in high power laser system have been investigated by differentmethods. Optical homogeneities of such crystals has been measured quantita-tively by Mark-Ⅲ laser digital wavefront interferometer. The results showthat the refractive index varies from 2×10^-6 to 3×10^-6. In order to get optimalpolishing and etching conditions for KDP, some experiments have been triedwith different reagents, and the results show that distillated water is a goodchemical polishing agent for the low index surfaces {100}、{101} and{001}. How-ever, the chemical etching agents for surfaces {100}、{101} and {001} aredifferent. Using the mixed agent CH₃COOH + H₂O, a satisfactory etchingon the {100} surface can be obtained at 17℃ in 4 minutes. It hasbeen demonstrated that the etch pits corresponding to dislocations couldbe revealed by repeated etching. The angle between the dislocation pro-pagation direction and the growth direction <001>as been calculated. Thedistribution of scattering particles and dislocations in KDP crystals can beclearly revealed by dynamic scanning microscopy. It should be mentioned that the distribution of scattering particles is regular and parallel to the {101}faces. In conclusion, most of the defects having influences on crystal qua-lity originate from seed crystals.更多还原