光学低通滤波器的光学传递函数分析

光电成像系统的抽样过程会引起图像频谱在频谱空间上的多次复制,如果抽样过程不满足系统的奈奎斯特条件,相邻的频谱项就会产生混叠.光学传递函数可以反映系统中光学成像,抽样和重建等各个过程对图像信号频谱的响应.通过对使用光学低通滤波器(OLPF)光电成像系统的光学传递函数的分析,表明光学低通滤波器可以有效地限制图像的频谱宽度,使抽样满足奈奎斯特条件,达到消除频谱混叠,改善重建图像质量的目的.

Optical Transfer Function of the Optical Low-pass Filter

Sampling of photoelectric imaging system could infinitely replicate the scene spectrum in spectrum space.If the sampling intervals were too large to satisfy the Nyquist criterion,the replicas would be overlapped and there was aliasing.The optical transfer function could demonstrate that how the optical imaging,integral sampling and reconstruction affected the overall performance.The optical transfer function was used for analysis of the photoelectric imaging system with OLPF.The results show that optic low-pass filter could effectively limit the scene spectrum width and critically satisfy Nyquist sampling condition,so the aliasing could be eliminated and quality of the image reconstructed is improved.