大型激光装置光学元件的稳定性设计

摘要

Large high-power solid-state laser facilities have a very high requirement for the total positioning error budget(<50 μm in general),so it is a very important to improve the stability of structure design.In this paper,the stability design is illustrated for several key optical and mechanical systems in the large laser facility.Then,several kinds of methods,such as reinforced concrete supports,truss structures,vibration isolation,integrated design and inhencing structure rigidness are used to reduce the effect of optical and mechanical structures on the ambient vibration and to improve the structure stablility,and finite element models are established to analyse the stablility of the key optical elements and support structures and to verify that the structure design is reasonable or not.The results show that the maximum rotation angles of key optical elements,i.e.cavity mirrors,Injection Mirror (IM),and the mirror in beam switch module are 0.14,0.423,and 0.394 jurad,respectively,and their design margins are greater than 1.5.These results indicate that the optical elements and support structures can satisfy the design indices for stability.%大型高功率固体激光装置通常要求总的打靶精度为几十微米,这对结构的稳定性设计提出了很高的要求.本文以一大型激光装置为背景,以关键光机系统为例进行稳定性设计.通过采用钢筋混凝土建筑结构、一体化结构和桁架结构、隔离振动源增加结构刚度等方式减小光机结构对环境振动的响应,提高结构的稳定性.然后,应用有限元理论对关键光学元件及其支撑结构的稳定性进行分析,以验证光机结构设计的合理性.分析结果显示,该系统中腔镜的最大转角为0.14 μrad,注入系统角漂元件的最大转角为0.423 μrad,光束切换模块反射镜的最大转角为0.394 μrad.计算结果表明:设计的结构合理可行,关键光学元件均满足稳定性设计指标的要求,且裕度系数＞1.5.