多光谱干涉成像仪频谱传输特性研究

Abstract

分析了多光谱干涉仪成像采样过程的频谱传输特性，针对频谱混叠现象采用以下措施进行消除：首先从光学器件参数上保证CCD上相邻两像元对应的最大光程差间隔不大于最大采样间隔，使其满足采样条件；其次通过引入抗光谱混叠滤波器——光学低通滤波器，利用石英晶体的双折射特性，将同一目标图像信息分成错开的o光像和e光像，分开的距离由石英晶体片厚度决定，以满足消除伪低频信号的条件。两种措施结合有效地消除了频谱混叠现象。 This paper analyzed the sampling frequency spectrum transmission characteristics of the inter-ference multi-spectral imaging interferometer imaging process, in view of the spectrum aliasing phenomenon using the following measures to improve: First choosing appropriate optical device parameters to guarantee the maximum optical path difference interval corresponding to any two adjacent pixels of the CCD is not greater than the maximum sampling interval, which can meet the sampling conditions; Secondly, by introducing anti-spectrum aliasing filter—optical low pass filter, which uses the quartz crystal’s birefringence properties to split the same target image information into stagger o image and e image; separate distance is determined by the thickness of quartz crystal slice. It can eliminate false low frequency signal. Combining the above two measures, it can eliminate the spectrum aliasing effectively.