对硅基片超薄多层金属镜在CO2激光辐照下的热特性进行了实验观测与理论分析.给出了超薄多层镜的结构设计方案,以及不同激光功率情况下镜面热变形与激光照射时间的关系曲线.结果表明,当反射镜吸收功率为120 W,光照时间为4 s时,普通硅镜的热变形量为0.71 μm;同等条件下硅基片超薄多层金属镜最大热变形量仅为0.25 μm.理论计算与实验结果基本相符.

In this paper, the thermal properties of a super-thin multilayer metal mirror with silicon substrate subjected to irradiation of high power lasers are experimentally demonstrated and theoretically analyzed. The structural designs for the mirror and the relations between thermal deformation and laser irradiating time are presented. The results show that under the condition that absorption laser power is 120 W, and laser irradiating time 4 s, the thermal deformation of the silicon super-thin multilayer mirror is 0.25 μm, but that of the general silicon mirror 0.71 μm. Theoretical calculations are relatively accordant with the experimental results.