大视场广角物镜畸变的实时数字校正

Distortion Correction of the Wide-Angle Objective Lens with Real-time Digital Technology

分析了利用数字图像处理进行畸变校正的理论 ,采用点阵样板校正的方法 ,对特殊的大视场广角物镜光学系统进行畸变的实时校正。通过计算机多项式拟合 ,得到该光学系统畸变的非线性变换关系 ,进而得到理想图像对应于畸变图像的空间位置及其偏移量 ,并以查找表的形式存于 EPROM中。利用实时数字逻辑电路 (FPGA) ,对畸变图像上的每个像素进行空间位置和灰度校正 ,最终得到无畸变的图像 ,完成畸变的实时校正过程。

It discussed the correcting theory by the digital image processing technology firstly, and then introduced correcting method for wide-angle objective lens. With this method a polynomial correction formula was developed with computer, and a non-linear transformation was obtained. The corrected image was mapped onto distorted image with the formula, the corresponding location and offsets in the distorted image was gotten and stored in the EPROMs as a lookup table. When every pixel in corrected image was processed with digital logic circuit and the method mentioned above, the correcting procedure was implemented completely.