For the continuous ultraviolet laser, the relation between the optimum transmission of the output coupler and efficiency of frequency doubling of the laser was considered, then we got the optimum crystal length. 在连续紫外的研究中,充分考虑到激光器输出镜的最佳透过率与倍频转换效率之间的关系,详细了计算了一定泵浦功率时的输出镜最佳透过率,并由此优化倍频晶体长度。