星敏感器遮光罩出口杂光的辐照度测试

Testing of stray light irradiance at exit of lens hood for star sensor

面向星敏感器在轨应用时杂光抑制的迫切需求,开展了星敏感器遮光罩出口杂光辐照度分布定量测试。基于微型光纤光谱仪、二维高精度位移台以及太阳模拟器搭建了可逐点扫描的杂光测试平台,并将辐射测量软件与运动控制软件进行有效整合,开发系统集成测试软件,完成遮光罩出口杂光辐照度分布的实时定量测量。针对获取的不同光照入射角下遮光罩出口处的测量计数值,根据测量时设定的积分时间及保存的暗背景数据以及光谱仪定标数据计算获得遮光罩出口处的杂光辐照度分布。数据处理结果表明:遮光罩在出口处的杂光辐照度约为102 W/cm^2,而且分布不均匀。基于误差分析理论构建了测量误差模型,误差计算结果为4.87%,表明了测量方案的合理性和可行性。测量数据可为星敏感器系统方案设计、论证、测试、定型及应用提供重要的技术支持。

Facing the urgent requirement of stray light suppression for the star sensor in orbit,stray light irradiance at the exit of the lens hood of a star sensor was determined quantitatively.Based on micro fiber optic spectrometer,two-dimensional high-precision displacement table and solar simulator,a stray light test platform which scans point-by-point was established.With the effective integration of radiation measurement software and motion control software,system integration test software was developed.Therefore,real-time quantitative measurement on irradiance distribution of the stray light at the exit of the lens hood was completed.Regarding of the measured values at the exit of the lens hood under different incident angles of irradiance,the irradiance distribution of the stray light at the exit of the lens hood was calculated according to the integration time set,dark background data and calibration data of spectrograph applied in the measurement.The data processing result shows：the irradiance of the stray light at the exit of the lens hood is about 102 W/cm2 and it is distributed unevenly.Based on the error analysis theory,a measurement error model is built with a calculated error of 4.87%,which shows the reasonableness and feasibility of the measurement scheme.The measurement data can provide important technical support for design,demonstration,testing,shaping and application of the star sensor.