1　前言近年 ,光刻和高密度多层基板的加工、DVD光盘的刻录、光造形、激光治疗和 DNA解析等许多产业、医疗领域 ,对相干紫外光源的需求增大了。固体激光器和非线性光学晶体相结合的全固态光源可以产生用半导体激光器难以振荡的紫外光。此外 ,与 Ar+激光器和受激准分子激光器等 1 Introduction In recent years, there has been an increase in the demand for coherent UV light sources in many industrial and medical fields, such as processing of lithography and high-density multilayer substrates, burning of DVD discs, shaping of light, laser treatment, and DNA analysis. An all-solid-state light source combined with a solid-state laser and a nonlinear optical crystal can produce ultraviolet light that is hard to oscillate with a semiconductor laser. In addition, with Ar + lasers and excimer lasers