An automatic optical inspection system for inspection of CMOS compact camera module assembly

This paper presents the development of an automatic inspection system to check lens focus status and white balance level and to inspect defects including black and white defect, dim defect, color defect, and line defects in manufacturing process of compact camera module. To check the imaging status and inspect the defects of compact camera module, a unique image capturing system is developed to get image data from CMOS sensor at high speed. It has a complex programmable logic device, and the camera link and the frame grabber is used to transfer and store images to PC. Several kinds of unique image charts are designed to inspect the various types of defects in compact camera module, and they are implemented and displayed on the LCD monitor directly to reduce handling and exchanging time of inspection charts during test procedures. Various image processing algorithms are developed to analyze the captured image from each test chart and to find and verify the defects of camera modules. The experimental results show that the proposed system is able to reliably inspect various types of defects with high precision and high speed in real manufacturing condition.