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Adaptive Thresholding Method Using Zone Searching Based on Representative Points for Improving the Performance of LCD Defect Detection
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 Title & Authors
Adaptive Thresholding Method Using Zone Searching Based on Representative Points for Improving the Performance of LCD Defect Detection
Kim, Jin-Uk; Ko, Yun-Ho; Lee, Si-Woong;
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 Abstract
As the demand for LCD increases, the importance of inspection equipment for improving the efficiency of LCD production is continuously emphasized. The pattern inspection apparatus is one that detects minute defects of pattern quickly using optical equipment such as line scan camera. This pattern inspection apparatus makes a decision on whether a pixel is a defect or not using a single threshold value in order to meet constraint of real time inspection. However, a method that uses an adaptive thresholding scheme with different threshold values according to characteristics of each region in a pattern can greatly improve the performance of defect detection. To apply this adaptive thresholding scheme it has to be known that a certain pixel to be inspected belongs to which region. Therefore, this paper proposes a region matching algorithm that recognizes the region of each pixel to be inspected. The proposed algorithm is based on the pattern matching scheme with the consideration of real time constraint of machine vision and implemented through GPGPU in order to be applied to a practical system. Simulation results show that the proposed method not only satisfies the requirement for processing time of practical system but also improves the performance of defect detection.
 Keywords
LCD Panel;Image Processing;LCD Defect Detection;Pattern Matching;Adaptive Thresholding;
 Language
Korean
 Cited by
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