激光窗口杂散光固气耦合热效应对光束质量的影响  

Influence of solid-gas coupling thermal effect caused by stray light from laser window on beam quality

作　　者：张玥婷 谭毅[1,2] 王继红[1,2] 彭起[1,2] 杨智焜 Zhang Yueting;Tan Yi;Wang Jihong;Peng Qi;Yang Zhikun(Key Laboratory of Optical Engineering,Chinese Academy of Sciences,Chengdu 610209,China;Institute of Optics and Electronics,Chinese Academy of Sciences,Chengdu 610209,China)

机构地区：[1]中国科学院光束控制重点实验室,四川成都610209 [2]中国科学院光电技术研究所,四川成都610209

出　　处：《红外与激光工程》2022年第9期227-235,共9页Infrared and Laser Engineering

摘　　要：为实现激光传输内通道密封,会在末端加装带倾斜角的窗口,但窗口的回射杂散光辐照管壁会引起结构温升,加热通道内气体引起热效应。针对密封窗口的回射杂散光辐照加热直管道问题,建立了直管道部分结构场-气体密度场-光场的耦合仿真模型,分析了不同管道材料、管壁厚度、管道结构形式对光束波前畸变的影响。分析结果表明:等质量的铝、铜、钢三种材料中,铝管道引起的光束波前畸变最小,仅为钢、铜的约50%;通过管道外侧增加散热翅片以及高导热碳膜的方式来降低壁温、改善波前畸变的效果并不理想,波前RMS值下降不超过3%;增加受辐照段管道壁厚、提升管道热沉是降低光束波前畸变最有效的方案,铝管壁厚由8 mm增加至16 mm可使管道出口处的波像差RMS值从36.1 nm下降到21.4 nm,各阶像差均得到改善。研究结果能够为内通道部分管道设计和热效应评估提供一定的参考。To achieve the sealing requirement, the laser transmission inner channel will add the window with an inclined angle at the end of thin channel, but the temperature rise caused by reflected stray light of the window irradiating the pipe wall will also increase the gas thermal effects. Aiming at the problem of irradiating and heating the straight pipe by the reflected stray light of the sealing window, a coupling simulation model of structure field-gas density field-optical field in the straight pipe was established, analyzing the influence of materials, wall thickness and structural forms on wave front distortion of beam. The analysis results indicate that among three materials of equal quality, aluminum, copper and steel, the beam wave front distortion caused by the aluminum pipe is the smallest, which is only 50% of that of steel and copper;reducing the wall temperature and the beam distortion by adding heat dissipation fins or high thermal conductivity carbon film outside the pipe is not ideal and the wave front RMS value is reduced by no more than 3%;increasing the wall thickness and raising the pipe heat sink are the most effective solutions to reduce the beam distortion, the RMS value of the aluminum pipe outlet reduces from 36.1 nm to 21.4 nm and each order aberration is improved while the wall thickness increasing from 8 mm to 16 mm. The research results can provide a certain reference for the pipe design of inner channel and thermal effects evaluation.

关 键 词：波像差 固气耦合 密封窗口 热效应 内通道 

分 类 号：TN24[电子电信—物理电子学]