中国激光, 2014, 41 (9): 0902007, 网络出版: 2014-07-22
基于激光光散射层貌术的蓝宝石内部缺陷检测系统
A Detecting System of Sapphire Internal Defects Based on Laser Light Scattering Tomography
摘要
蓝宝石是制作发光二极管(LED)衬底的基本材料,其质量直接影响高亮度LED衬底的晶片制造成品率,对于棒状蓝宝石晶体内部缺陷的检测定位能极大地降低生产成本,提高成品率。针对蓝宝石衬底加工要求,在机器视觉技术的基础上,利用LabVIEW及NI公司的图像采集卡和数据采集卡搭建了一个基于激光光散射层貌术的蓝宝石内部缺陷检测定位系统。系统利用高强度的线状激光照射下缺陷产生的光散射效应对蓝宝石晶体进行逐层扫描和图像采集,运用图像增强、图像分割及图像提取等图像处理手段对采集到的图像进行缺陷提取和分析,实现了对蓝宝石内部缺陷的检测和定位,具有很高的实时性和可视化效果。实验结果表明,该系统能有效地识别出蓝宝石晶体中的散射颗粒缺陷,并对其在棒状蓝宝石晶体深度方向上准确定位。
Abstract
As the basic material of light emitting diode (LED) substrate, the quality of sapphire directly affects the production yield of high-brightness LED substrate chips. The detection and positioning of internal defects in sapphire crystal bar can greatly reduce the production cost and improve the yield. Based on machine vision technique, an internal defect detection and positioning system are bulit for sapphire on the basis of laser light scattering tomography taking the processing requirements on sapphire substrate into consideration. LabVIEW and image acquisition card and data acquisition card from NI Company are adopted in this system. The detection and positioning of internal defects in sapphire crystal is realized by scanning the sapphire crystal layer by layer through the light scattering effect generated by the irradiation of high-intensity linear laser on defects. A lot of image processing methods such as image enhancement, image segmentation and image extraction are adopted to extract and analyze the defects, enhancing the real-time performance and visuality of this system. The experimental results show that this system can identify the scattering particle defects in sapphire crystal effectively, and position them in depth direction accurately.
刘洋, 徐文东, 赵成强, 胡永璐, 刘涛, 王闯. 基于激光光散射层貌术的蓝宝石内部缺陷检测系统[J]. 中国激光, 2014, 41(9): 0902007. Liu Yang, Xu Wendong, Zhao Chengqiang, Hu Yonglu, Liu Tao, Wang Chuang. A Detecting System of Sapphire Internal Defects Based on Laser Light Scattering Tomography[J]. Chinese Journal of Lasers, 2014, 41(9): 0902007.