新型偏振干涉成像光谱仪信噪比研究

基于辐射度学、电磁与偏振理论和傅里叶变换光谱学理论，从理论和实验上对超小型稳态偏振干涉成像光谱仪的信噪比进行了深入地分析与讨论.推导出了其信噪比的理论计算公式；采用计算机模拟给出了傍轴条件下信噪比随入射角的变化规律；深入分析了偏振干涉成像光谱仪所特有的偏振化方向对信噪比的影响.在调制度等于0.6，0.7，0.8，0.9，1.0时，给出信噪比随偏振器光轴偏角的变化关系，并给出最优化值.在最优化情况下，采用计算机模拟得出了信噪比随探测器像元数的变化规律，与干涉成像光谱实验结果完全相符.理论与实验结果表明，该偏振干涉成像光谱仪在高调制度的情况下具有高通量、高信噪比的显著特点，适合于航空航天、远距离目标和微弱信号的探测.该研究为新型偏振干涉成像光谱技术的研究和新型成像光谱仪的设计、研制和工程化提供了重要的理论依据和实践指导.

Study of SNR of a novel polarization interference imaging spectrometer

Based on radiometry，electromagnetism and polarization theories and the Fourier transform spectroscopy，an in-depth study is conducted on the SNR of the self-developed ultra-compact static polarization interference imaging spectrometer (USPIIS) theoretically and experimentally. The theoretical equations of its SNR are deduced. Under paraxial approximation，the curve of the SNR changing with incidence angle is given via computer simulation. How the polarizing directions affect the SNR of USPIIS，which is a particular feature of the polarization interference imaging spectrometer，is deeply studied. When modulation depth equals 0.6，0.7，0.8，0.9 and 1.0，the curves of the SNR changing with polarizing directions are given respectively; after which the optimum value is recommended. Under optimum conditions，the changing laws of SNR with the elements of detector are obtained，which turned out the same as the prediction of the theory. The theoretical and experimental results both indicate that the novel imaging spectrometer has the properties of high throughput and high SNR under the condition of high modulation depth，which is suitable for aviation，remote sensing，weak signal testing applications. The work can provide theoretical basis and guidance for the design，development and engineering of polarizer，interferometer and polarization imaging interferometer.