宽场偏振干涉成像光谱仪的调制度研究

Interference visibility of wide-field-of-view polarization interference imaging spetrometer

干涉成像光谱技术是一种集双光束干涉技术、二维成像技术以及高分辨率光谱技术于一体的高新遥感探测技术,常用来进行监视、识别和探测各种民用和军事目标。基于双折射晶体的宽场偏振型干涉成像光谱仪是该技术中的一种典型代表,组成其系统的偏光元件的性能是决定其成像质量和光谱复原精度的关键因素。论文考虑元件偏振误差和延迟误差对光路传播的影响,采用偏振追迹法推导出了系统干涉调制度的理论表达式,给出了其随入射角、入射波长、入射方位角以及元件偏振化方向和相位延迟量的变化特性,并定量分析了其允差范围。这为基于偏光器件成像光谱仪的系统设计、高光谱复原以及工程实践提供了重要的理论指导和技术支持。

Interference imaging spectroscopy(IIS) is a novel high technology integrated by the two-beam interference technique, 2D imaging technique and spectroscopy with high resolution. The wide-field-ofview polarized type is an attractive scheme in IIS. It employs polarized components to realize interference and thus the image quality and spectrum reconstruction are principally determined by the characteristics of these polarization components. In this work, theoretical analysis of the interference visibility was performed by considering the polarization deviations and the retardation deviation of elements. The theoretical expression of interference visibility was deduced by polarization tracing method. The varying characteristics of interference visibility with incident angle, wavelength, azimuth angle, polarization direction and phase retardation were presented and the permissible deviation was quantitatively analyzed. This work would provide suggestions for system design, hyperspectral reconstruction and engineering practice of spectrometers composed of polarization components.