中文摘要：

考虑空间环境中温度是光学系统成像质量的主要影响源,针对离轴三反射光学系统提出了一套由有限元分析到光学分析的热光学分析方法。在有效分析均匀温度场对系统影响的基础上,采用有限元分析得到温差影响下的镜面面形畸变,并用Zernike多项式拟合畸变面形;将Zernike系数代入光学设计软件CODE V,理论分析了温差影响下的光学系统成像质量,提出了光学系统温控指标。以温控指标为依据对光学系统采用主动热控进行热光学试验,所得试验结果均达到56lp/mm下光学系统全视场MTF值〉0.2的光学参数要求,实验结果证明了理论分析的准确性和温控指标的合理性。

英文摘要：

In the space,temperature is the key factor influencing the optical system imaging quality.To investigate the effect of temperature on the off-axis three mirror system,a thermal optical analysis method from finite element analysis to optical analysis was presented.On the basis of analysis results of the optical system in uniformly distributed temperature fileds,the surface aberration of mirrors with temperature gradients was obtained by using a finite element analysis software,and the surfaces with aberration were fitted with the Zernike Polynomials.Then,the Zernike coefficients were carried into the software CODE V,the imaging qualities of the system with difference temperature gradients were analyzed,and thermal control requirements were determined.Finally,a thermal optical experiment was carried out to test the optical system with active thermal controls.Experimental results show that the MTF of full field in the optical system is more than 0.2 in 56 lp/mm,which means the optical parameters meet the the requirements of optical system.Results also verify the correctness of the theory and the reasonabity of thermal control requirements.