傅里叶望远镜外场实验与结果分析

为了分析外场环境因素对傅里叶望远镜成像质量的影响和验证成像过程不受下行链路大气扰动影响的特点,开展了傅里叶望远镜外场实验研究.外场实验在室内实验的发射光学系统的基础上增加了主镜、次镜和会聚透镜组对目标散射光进行3次会聚仿真实际系统的成像过程,同时将目标与主镜、主镜与次镜分别拉开100 m距离验证成像系统不受下行链路大气扰动影响的特点.实验利用胶片打印的2种不同的卫星图片作为目标,获得了Strehl值分别为0.44、0.39的无大气扰动的外场重构图像和Strehl值分别为0.43、0.38的含大气扰动的外场重构图像.通过比较外场重构图像与室内重构图像的Strehl值,得出发射光学系统中光束的振动对成像有较大影响.分析发现无大气扰动外场重构图像与含大气扰动外场重构图像的Strehl值相近,从而验证傅里叶望远镜成像过程不受下行链路大气扰动的影响.

Field Experiment and Result Analysis of Fourier Telescopy

In order to study effects of outdoor factors to Fourier telescopy imaging and validate properties of imaging immune to down-link atmospheric turbulence,outdoor experiments were developed.Under the ground of lab experiments,outdoor experiments added primary mirror,secondary mirror and condense lens to simulate the real system imaging.The distance between object and primary mirror and the distance between primary mirror and secondary mirror was put away 100m,separately,to validate the property of Fourier telescopy imaging immune to atmospheric turbulence.Using 2 different satellite films as objects,the outdoor reconstructed images were gotten with the Strehl value 0.44 and 0.39 without turbulence,separately,and Strehl value 0.43 and 0.38 with turbulence,separately.Compared the reconstructed images of outdoor with lab,the conclusion was gained that libration had obvious effect on imaging.The result that the Strehl value of outdoor imaging was similar to lab imaging confirmed the fact that Fourier telescopy imaging was immune to down-link atmospheric turbulence.