利用猫眼回波的变化研究焦平面上硅在激光辐照下的损伤演化。随着激光辐照时间的增加, 回波图像出现抖动, 产生新的纹理, 判定焦平面上硅受到损伤。损伤对应的回波图像面积不断扩大, 损伤区内光斑结构逐渐变得复杂, 且光斑面积不断减小, 最终形成动态稳定的损伤回波图像。依据回波图像的变化分析硅的损伤形貌, 依次出现表面氧化、小尺度形貌损伤、损伤面积扩大等现象。初步分析了回波图像纹理特征与焦平面上硅损伤形貌的对应关系, 认为回波图像损伤区光斑的自相关性与角二阶矩随着损伤形貌粗糙度的增大而减小。

Detecting silicon damage evolution induced by laser irradiation on the focal plane was researched through the change of cat′s eye echo. With the time increase of laser irradiation, the echo images started to shake and new texture appeared, which indicate the silicon was damaged. The area of echo images corresponding to the silicon damage expanded unceasingly. The facular structure in the damaged echo image became complicated and the facular area became smaller. The damaged echo image was dynamic stability under the laser irradiation at last. According to the change of echo images, the silicon damage morphology were analyzed. The phenomena of surface oxidation, small scale damage and the expanding of damaged area were observed. The corresponding relationship between the echo image texture feature and the silicon damage morphology was analyzed preliminarly. The correlation and angular second moment would be decreased if the roughness of the damage morphology increased.