Abstract: In the Flat Panel Display (FPD) industry, Automatic Optical Inspection (AOI) is one of the most essential processes for inspection of Liquid Crystal Display (LCD) panels. For this purpose, autofocusing is an important function for which precise moving distance control in μm is required, considering the unit of focal length of autofocusing equipment. A Z-axis test bench using a step motor was built for autofocusing of the AOI camera and the moving distance was controlled by a Micro Controller Unit (MCU). A user-friendly Graphic User Interface (GUI) platform was implemented as the supervising system. The validation test confirmed the controllable minimum moving distance and verified the equipment reliability through iterative experiments. The test results can also be used to find the appropriate application range.
Bonghwan Kim, Dongsu Lee, Sun Lu and Kyunghan Chun, 2019. GUI-based Autofocusing System for AOI of FPDs. Journal of Engineering and Applied Sciences, 14: 5955-5961.