Fizeau干涉仪主机的热稳定性设计与分析

Design and analysis of thermal stability for main frame in Fizeau interferometer

搭建了光-机-热耦合模型,用于分析Fizeau干涉仪光机系统的热稳定性,并研究了该系统的计算流程、环境温度和系统光学质量的随机性、系统光学质量与环境温度的关系等。首先,根据实验室温控条件,建立环境温度的随机分布模型,进行了光-机-热耦合分析并计算不同温度下光机结构的热分布和结构变形;然后,通过Zernike多项式拟合透镜表面面形和曲率半径,利用光学仿真软件分析变形后的光学系统;最后,对系统光学质量进行概率分析,评价了系统的热稳定性。分析结果表明,温度控制在(22±0.1)℃时,在2σ的置信水平下,Fizeau干涉仪的出射光波前的重复性可以达到0.016%λ,基本满足干涉仪主机光机系统的重复性要求。

An optical-structural-thermal model was built to analyze the thermal stability of an optical-structural system in the Fizeau interferometer.The analyzing process of the model,random distribution of environment temperatures,and the optical performance of the system were researched.Firstly,a random model for environment temperatures was built based on the thermal control system,and the thermal distribution and deformation of the optical-structural system were computed.Then,the surface forms and curvature radii of the optical component were fitted with the Zernike polynomial,and the fitted optical system was analyzed with the optical software.Finally,a random model to indicate the relationship of optical performance and temperature was built and the thermal stability of the main frame in the interferometer was discussed through analyzing the random model.Results indicate that the repeatability of the optical-structural system is 0.016%λ under believable level of 2σ when the temperature is（22±0.1）℃,which satisfies the requirements of the Fizeau interferometer for stability.