基于哈特曼-夏克波前传感器的模糊图像复原方法

Method for Blurred Image Restoration Based on Hartmann-Shack Wavefront Sensor

离焦模糊图像的清晰度较低,因此必须对其进行复原。传统方法通常采用圆盘或高斯函数来近似离焦造成的点扩散函数,复原效果不够理想。为此,提出利用哈特曼-夏克波前传感器探测离焦波前,根据所得波前计算光学系统的点扩散函数,并采用Richardson-Lucy算法对模糊图像进行复原。搭建了实验用的光学系统,采集了离焦模糊图像以及相应的波前信息,获得了清晰的复原图像,并利用客观图像评价方法对退化图像和复原图像进行了评价,同时与传统方法得到的复原图像进行了比较。实验结果表明,该方法能精确重建点扩散函数,有效提高图像的质量。

Since blurred image caused by defocus is of low clarity, image restoration is necessary. For traditional methods, circular disk or Gaussian function is adopted to approximate point spread function （PSF） caused by defocus, and the restored image is not ideal. Therefore, a method using Hartmann-Shack wavefront sensor to detect the wavefront distorted by defocus, calculating the PSF of the optical system with the obtained wavefront, and adopting the Richardson-Lucy algorithm to deblur the degraded image is proposed. An experimental system is built, from which both the blurred image and the corresponding wavefront information are collected. Clear restored images are obtained. Objective image quality assessment methods are used to evaluate the degraded and restored images. In addition, the restored images are also compared with the results obtained by traditional methods. Experimental results show that the proposed method can accurately reconstruct the PSF, and the quality of the image is efficiently improved.