一种新型光学快速自动聚焦系统

为满足基于机器视觉的工业检测系统中对自动对焦快速性的要求,提出了一种基于激光技术的新型嵌入式高速对焦系统.该方法利用在同一光路中激光与可见光互不影响的特性和DSP高速图像处理的能力,通过检测特殊设计光学回路反射回来的激光光斑信息,主动控制运动执行机构实现工业检测系统显微镜的快速和稳定对焦.该对焦方法改善了TFT-LCD光学检测系统中基于被动的图像处理和基于主动测距等传统对焦方式精度低和速度慢等缺陷.测试结果表明,该新型对焦系统极大的缩短了对焦的时间,并且提高了对焦系统的控制精度,满足了工业光学检测系统中实际应用的要求.

A New Type of High-speed Automatic Focusing System

In order to meet the requirements of fast autofocus based on machine vision in industrial inspection systems,a new type of laser-based and high-speed embedded autofocus system is put forward.The design combines the characteristics of laser and visible light without affecting each other in the same optical path and the capabilities of Digital Signal Processing(DSP)high-speed image processing,and controls motion actuator to achieve fast and stable focusing of microscope in the industrial inspection systems by inspecting the laser facula information reflected back by optical path designed specially.Moreover,the design improves traditional method defects of slow accuracy and speed in TFT-LCD optical inspection system,such as based on the passive image processing and active range auto-focus measurement.Test results show that the new focusing system greatly shortens the focusing time,increases the control precision of the focusing system,and meets practical application requirements in the industrial optical inspection systems.