Journal of Korea Multimedia Society (한국멀티미디어학회논문지)

Korea Multimedia Society (한국멀티미디어학회)
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Segmentation of Defective Regions based on Logical Discernment and Multiple Windows for Inspection of TFT-LCD Panels

TFT-LCD 패널 검사를 위한 지역적 분별에 기반한 결함 영역 분할 알고리즘

  • 정건희 (경북대학교 전자전기컴퓨터공학부) ;
  • 정창도 (경북대학교 전자전기컴퓨터학부) ;
  • 윤병주 (경북대학교 전자전기컴퓨터학부) ;
  • 이준재 (계명대학교 게임모바일콘텐츠학과) ;
  • 박길흠 (경북대학교 전자전기공학부)
  • Received : 2011.09.09
  • Accepted : 2011.11.11
  • Published : 2012.02.29
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Abstract

This paper proposes an image segmentation for a vision-based automated defect inspection system on surface image of TFT-LCD(Thin Film Transistor Liquid Crystal Display) panels. TFT-LCD images have non-uniform brightness, which is hard to finding defective regions. Although there are several methods or proposed algorithms, it is difficult to divide the defect with high reliability because of non-uniform properties in the image. Kamel and Zhao disclosed a method which based on logical stage algorithm for segmentation of graphics and character. This method is a one of the local segmentation method that has a advantage. It is that characters and graphics are well segmented in an image which has non-uniform property. As TFT-LCD panel image has a same property, so this paper proposes new algorithm to segment regions of defects based on Kamel and Zhao's algorithm. Our algorithm has an advantage that there are a few ghost objects around the defects. We had experiments to prove performance in real TFT-LCD panel images, and comparing with the FFT(Fast Fourier Transform) method which is used a bandpass filter.

본 논문은 비전장비의 결함 검사 시스템을 위한 불균일한 휘도분포를 가지는 TFT-LCD 영상에서 결함 영역을 분할하는 방법을 다룬다. 불균일한 휘도분포 때문에 결함의 영역을 찾기 어려우며 이를 위해 많은 방법들이 제안되었다. Kamel과 Zhoa는 문자 및 그래픽의 분할을 위해 논리적 단계화 방법을 제안하였고, 이 방법은 공간상에서 수행되어지는 지역적 분할 방법으로 불균일한 분포 상에서도 문자가 잘 분할되는 장점이 있다. TFT-LCD의 저해상도 영상도 배경의 분포가 불균일하여 본 논문에서는 Kamel과 Zhoa의 방법을 답습하여 새로운 결함 영역 분할 방법을 제안한다. 제안한 방법은 결함주위에 발생하는 과검출(Ghost object)이 적은 장점이 있으며 제안 방법의 성능을 증명하기위해 실제 결함이 존재하는 TFT-LCD 영상을 이용하여 실험하고, 주파수상에서 많이 사용되는 FFT의 밴드패스 필터를 이용한 분할 방법과 비교하였다.

Keywords

References

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