基于局域信号增强的光学元件损伤检测  

Optical Damage Inspection Based on Local Signal Enhancement

作　　者：田玉婷 邬融[1] 杨野 Tian Yuting;Wu Rong;Yang Ye(Key Laboratory of High Power Laser and Physics,Shanghai Institute of Optics and Fine Mechanics Chinese Academy of Sciences,Shanghai 201800,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]中国科学院上海光学精密机械研究所高功率激光物理重点实验室,上海201800 [2]中国科学院大学,北京100049

出　　处：《中国激光》2018年第11期137-144,共8页Chinese Journal of Lasers

基　　金：中国科学院高功率激光物理重点实验室基金(CXJJ-16S040)

摘　　要：为实现高功率激光驱动器中大口径光学元件表面疵病的低漏检率识别,针对微弱疵病的低信噪比特点,提出了改进的局部信号强度比自适应检测算法。利用信号图像中疵病与邻域非疵病区域的信号强度差异,构造了一类滤波模板对信号图像进行自适应局域增强,可有效提高疵病信号强度值和显著增强信号图像的疵病信噪比。对种子图像进行种子点的筛选与自适应区域生长,并进行精确提取完成损伤区域的完整分割。改进后的局部信号强度比算法能有效识别低信噪比微弱疵病,在全内反射暗场侧向照明成像条件下,可识别出约30μm的疵病坏点。与现有的局部信号强度比算法相比具有更低的漏检率,结果表明等价圆直径在50μm以上的损伤点的漏检率低于0.4%。To realize the recognition of surface damages with a low missed detection rate on large aperture optical elements in a high power laser driver and according to the low signal-to-noise ratio characteristic of micro-size damages, an adaptive detection algorithm is proposed based on the improved local signal intensity ratio. The signal intensity difference between the damages and their neighbored non-damage area in signal images is adopted to construct a filter template for the adaptive local enhancement of signal images. Thus, the damage signal intensity can be enhanced effectively and the signal-to-noise ratio of damage on signal images can also be improved significantly. As for the seed images, the seed selection and the adaptive regional growth are performed, and the complete segmentation of damage regions is finished by the accurate extraction. The improved local area signal intensity ratio algorithm can be used to effectively recognize the small-size damage points with a low signal-to-noise ratio. Under the total internal reflection lateral illumination in dark fields, the damage points with size of about 30μm can be recognized. The missed detection rate is lower than that of the existing local area signal strength algorithm. The results show that the missed detection rate is below 0.4% for damage points with equivalent diameter of above 50 μm.

关 键 词：测量 损伤检测 局部信号强度比 区域生长 图像分割 

分 类 号：TN247[电子电信—物理电子学]