光学学报, 2018, 38(7): 0712005, 网络出版: 2019-05-09

偏振遥感器带内相对光谱响应度定标方法研究

Research on Calibration Method of In-Band Relative Spectral Responsivity of Polarization Remote Sensor
作者单位

1中国科学技术大学环境科学与光电技术学院, 安徽 合肥 230026

2中国科学院安徽光学精密机械研究所通用光学定标与表征技术重点实验室, 安徽 合肥 230031

摘要
带内相对光谱响应度是检测和评估偏振遥感器带内响应非一致性的基本参数。采用基于激光抽运氙灯光源的单色仪、消偏器、参考探测器和45°分束镜,搭建了一套偏振遥感器相对光谱响应度测量装置。该装置采用消偏器消除单色仪输出的偏振特性,通过光谱偏振分析仪(SPOLA)进行消偏精度的测量和验证。采用分束镜同步测量的方法来降低光源的非稳定性影响,提高测量精度和效率。采用成像区域大气校正仪490 nm和870 nm偏振通道作为应用案例,开展了带内相对光谱响应度的整机测试实验。实验结果表明,大气校正仪中心波长测量极差值与带宽均值的比值精度在0.25%以内,满足带内响应非一致性小于0.6%的定标要求。
Abstract
The in-band relative spectral responsivity is a basic parameter for the detection and evaluation of the in-band response non-uniformity of a polarization remote sensor. A set of devices to measure the relative spectral responsivity of the polarization remote sensor is assembled, which consists of a laser pumping xenon light source monochromator, a depolarizer, a reference detector and a 45° beam splitter. The depolarizer is utilized to eliminate the output polarization characteristics of the monochromator, and the spectro-polarimetric analyzer (SPOLA) is utilized to measure and verify the depolarization accuracy. The synchronization measurement method of beam splitter is utilized to reduce the instability of the light source and to improve the measurement accuracy and efficiency. By taking 490 nm and 870 nm polarization channel of the atmospheric corrector as an example of application, the experiment of in-band relative spectral responsivity in instrumental level measurements is carried out. The experimental results show that the accuracy of the ratio between measured range value of the center wavelength and the average value of the bandwidth for atmospheric corrector is within 0.25%, which meets the in-band responsivity non-uniformity calibration requirement of less than 0.6%.
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