高功率激光晶体加工技术的研究

针对高功率激光器中使用的激光晶体关键元件,开展了晶体的先进加工技术的研究。根据LBO及YCOB晶体材料的加工特性,选取了定向切割、研磨、预抛光、磁流变抛光、合成盘抛光和机械化学抛光的总体技术路线。对不同种类晶体加工设计了不同的工艺路线,开展了相关加工工艺研究。其中LBO晶体的面形收敛工艺主要采用磁流变抛光,YCOB晶体的面形工艺主要采用合成盘抛光。通过组合加工工艺,获得了高质量的晶体加工指标,LBO晶体透射波前0.12λ(λ=632.8nm),粗糙度0.77nm;YCOB晶体面形0.11λ,粗糙度0.68nm。确定了晶体元件的整体加工技术路线,并对整个工艺流程开展了工艺实验研究,取得了较好的实验效果,实现了激光晶体的高质量加工指标。

Manufacturing process of high-power laser crystals

The paper presents the advanced manufacturing process of crystals which are extensively used in high-power laser devices. Based on the properties of the typical LBO and YCOB crystals, a procedure including cutting, grinding, pre-polishing, MRF polishing, composite lap polishing and CMP polishing was proposed. Experiments were undertaken for various crystals and correlative manufacturing technologies were studied. Different polishing approaches were used, in which the MRF process was employed for LBO crystal and the composite lap polishing process was utilized for YCOB crystal. The results show that, by combining the manufacturing technologies, the surface figure and roughness of LBO reached 0.12 and 0.77 nm, and the surface figure and roughness of YCOB reached 0.11 and 0.68 nm respectively.