Software Design Of Automatic Inspection System For ITO Electrode Pattern

ITO is an important part of LCD and needs to be emphatically inspected by AOI system. This inspection will affect quality and turnoff ratio of LCD product, and hold very important status in the process of LCD manufacture.The process of LCD manufacture has very strict requirements for many factors, such as craftwork, facility, material and environment. But high effective, speedy and exact inspection of ITO patterns is still technical problem. Because LCD display technology tends to become high-class, precisely and integrated . line-thickness and space between lines become thinner and thinner. At present, ITO automatic inspection technology still doesn't get perfect and mature, and inspection arithmetic also needs more research.This paper studies currently urgent ITO auto inspection technology, and brings forward an optimum 1-D projection image segmentation method based on 2-D gray histogram, connectivity preserving image size reduction arithmetic and simple, efficient and fast look-up table thinning method. This paper also inspects common defects synthetically using mathematic morphology method, and puts forward a hybrid method of feature matching and image fixed orientation.During design and implementation of ITO AOI system, we give design patterns and realization details of every process, and adopt optimum 1-D projection image segmentation method based on 2-D gray histogram, in order to obtain as much information as 2-D gray histogram, we realize 1-D searching speed, improve speed and quality of segmentation; connectivity preserving image size reduction arithmetic decreases information storage; efficient and fast look-up table thinning method accelerates feature extraction; And hybrid method of feature matching and image fixed orientation may exactly inspect defects of ITO patterns. Subsequently we discuss how to implement on Visual C++ platform.Finally, we talk about insufficiency and keep on development of defect-inspection algorithms.