大口径光学薄膜激光预处理系统缺陷检测控制

Defect detection and control of a laser conditioning system for large diameter optical film

大口径光学薄膜激光预处理系统是通过确定大口径光学薄膜的缺陷分布,对大口径光学薄膜的缺陷进行准确地激光修复。为了达到保障系统运行速率与检测精度的目的,采用对缺陷检测部分的运动控制与补偿进行改进的方法,进行了理论分析和实验验证,取得了在不同运动速度下光栅尺的读数精度、伺服电机的控制精度以及图像采集偏移量的补偿值等数据。结果表明,采用伺服电机控制运动并结合硬件通过指定点比较函数控制采图点的方式保证系统在高速运动(20mm/s)情况下,对系统进行多次运动校正和适当的运动补偿,可以提高大口径光学薄膜激光预处理系统缺陷检测的精度,从而改善大口径光学薄膜激光预处理的效果。

A laser conditioning system for large-aperture optical film is to determine the defect distribution of the largediameter optical film and repair the defects with laser. In order to guarantee the speed and accuracy of detection system, the motion control and compensation of the defect detection part was improved. Theoretical analysis and experimental verification were conducted, and the reading accuracy of gratings, the servo control accuracy and the compensation value of image acquisition offset were obtained at different velocities. The results show that the detection accuracy of the laser conditioning system for largediameter optical thin-film can be improved by means of multiple motion corrections and an appropriate motion compensation if controlling the motion of the servo motor and the map points based on point comparison function at high speed（20mm/s）, thereby improving its laser pretreatment effect.