第18卷第2期 2010年2月
文章编号
1004-924X(2010)02-0289-05
光学精密工程
Optics and Precision Engineering
Vol.18No.2
Feb.2010
离轴三反空间光学望远系统的杂散光抑制
颜昌翔1，许杰1,2，彭岩1,2
（1.中国科学院长春光学精密机赫与物理研究所，吉林长春130033；
2.中国科学院研究生院，北京100039)
摘要：以点源透过率(PST)为评价标准，对--个离轴三反空间望远系统的杂散光进行了分析，并给出了分析结果。通过建立系统的实体模型，确定了一次、二次散射路径，采用改进的蒙特卡洛法，对20"之间各离轴角分别进行光线追迹。对模型的分析结果表明，系统产生杂散光的主要原因为一次散射，与光学系统结构密切相关。离轴角为土0.1"时，PST分别等于3.56和4.02，离轴角为土±20°时，PST分别为6.63×10-和4.58×10-，实验表明，通过加人遮光罩及减小镜面散射率可减少杂散光。与离轴两反望远系统相比，三反系统的杂散光水平在大离轴角时偏大1到2个数量级，但可满足使用要求。
关键调：离高轴三反望远镜；杂散光；散射路径；点源造光率(PST)
中图分类号：TH743
文献标识码：A
Straylightsuppressionofthree-mirroroff-axisspaceopticaltelescope
YAN Chang-xiang',XU Jie-*,PENG Yan'-2
(1.Changchun Institute of Optics,FineMechanics andPhysics, ChineseAcademy ofSciences,Changchun130033,China;
2.Graduate University of Chinese Academy of Sciences, Beijing 100039,China)
Abstract: Stray light analysis on a three-mirror off-axis space telescope was presented in this articie based on the measurement of Point Source Transmittance(PST). The entity model of the system was established to determine the first and second order scattering paths,and then different off-axis angles in ranges of 2o° were calculated by the improved Monte Carlo ray trace method. Results indicate that the stray light mainly is composed of the first order scattering, which is related closely to the structure of the optical system. Furthermore, the PSTs are 3. 56 and 4. 02 at ±0. 1° off-axis angles, 6. 63 X 10-5 and 4.58X105 at ±20° off-axis angles. Experiments also show that the stray light can be re-duced by modifying the baffles and changing the mirror's scattering rate, Compared with that of the two-mirror off-axis telescope, the stray light of three-mirror system is graveness at the big off-axis an gle, but it can meet the design requirements.
Key words: three-mirror off-axis telescope; stray light; scattering path; Point Source Transmittance
(PST)
收稿日期：2008-11-04；修订日期：2008-12-10，
基金项目：国防预研基金资助项目（No.05001SA050）