光学稀疏孔径成像系统采用多个独立子望远镜按阵列排布来等效一个大口径望远镜,其直接输出图像需要进行后期数字图像处理以获得与等效口径望远镜直接成像质量相同的复原图像。在图像复原方法中,维纳滤波方法是最常使用的一种图像复原算法,这种方法需要系统的实际点扩展函数作为参数。然而对于一个大口径的光学稀疏孔径成像系统,其实际点扩展函数往往难以测量。相反,根据子望远镜的阵列排布形式可以非常容易地计算出系统的理想点扩展函数。通过理论推导和仿真实验分析了使用计算的点扩展函数代替实际的点扩展函数进行图像复原的可行性。

The digital post-processing is needed to restore the image of high quality from the blurring image output directly from optical sparse aperture imaging systems. The common method for post-processing is the Wiener filter,where the important parameter is the point spread function (PSF) which should be known. The Wiener filter will deconvolve the convolution effect if the PSF is the precise impulse response of the optical sparse aperture system. Usually it is hard to measure the PSF experimentally. On the contrary,it is easy to calculate the PSF based on designed array configuration of the optical sparse aperture system. In order to evaluate whether the calculated PSF is adaptable to the image restoration,a theoretical analysis of the image restoration has been done by using these two kinds of PSFs. The results show that the calculated PSF works well in the case that the co-phasing error is small,while the measured PSF is ineffective.