Journal of Korea Society of Industrial Information Systems (한국산업정보학회논문지)

Korea Society of Industrial Information Systems (한국산업정보학회)
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A TFT-LCD Defect Detection Method based on Defect Possibility using the Size of Blob and Gray Difference

블랍 크기와 휘도 차이에 따른 결함 가능성을 이용한 TFT-LCD 결함 검출

  • Received : 2014.05.09
  • Accepted : 2014.07.20
  • Published : 2014.12.30
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Abstract

TFT-LCD image includes a defect of various properties. TFT-LCD image have a recognizable defects in the human inspector. On the other hand, it is difficult to detect defects that difference between the background and defect is very low. In this paper, we proposed sequentially detect algorithm from pixels included in the defect region to limited defects. And blob analysis methods using the blob size and gray difference are applied to the defect candidate image. Finally, we detect an accurate defect blob to distinguish the noise. The experimental results show that the proposed method finds the various defects reliably.

TFT-LCD 영상은 다양한 특성의 결함을 포함하고 있다. 배경 영역과의 휘도 차이가 커서 육안으로 식별 가능한 결함부터 휘도 차이가 매우 적어서 육안 검출이 어려운 한도성 결함까지 포함한다. 본 논문에서는 휘도 차이를 이용하여 결함 영역에 포함될 확률이 높은 결함 화소부터 순차적으로 단계를 진행하면서 결함 후보 화소를 검출하고, 검출된 후보 화소를 블랍으로 구성하여 블랍의 크기와 주변 영역과의 휘도차이를 이용한 기법을 통해 최종적으로 결함 영역과 잡음을 구분하여 검출하는 알고리즘을 제안한다. 제안한 알고리즘의 타당성을 확인하기 위해 다양한 결함을 포함하는 영상에 대한 실험 결과를 살펴봄으로써 신뢰도 높은 결함 검출 결과를 입증하였다.

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References

  1. Y. C. Cho, B. J. Choi, and J. O. Yoon, "A Study on the Development of Backlight Surface Defect Inspection System using Computer Vision," Journal of the Korea Industrial Systems Research, Vol. 12, No. 3, pp. 116-123, 2007.
  2. C. B. Moon, Y. H. Ahn, H. Y. Lee, B. M. Kim, and D. W. Oh, "Implementation of Automatic Detection System for CCFL's Defects based on Combined Lighting," Journal of the Korea Industrial Systems Research, Vol. 15, No. 2, pp. 69-80, 2010.
  3. X. B. C. Zhuang and H. Ding, "A New Mura Defect Inspection Way for TFT-LCD using Level Set Method," IEEE Signal Processing Letter, Vol. 16, Issue. 4, pp. 311-314, 2009. https://doi.org/10.1109/LSP.2009.2014113
  4. Y. Mori, R. Yoshitake, and T. Tamura, "Evaluation and Discrimination Method of 'Mura' in Liquid Crystal Displays by Just Noticeable Difference Observation," Proceedings of SPIE, October 7, 2002, pp. 715-722.
  5. J. H. Oh, B. J. Yun, S. Y. Kim, and K. H. Park, "A Development of the TFT-LCD Image Defect Inspection Method Based on Human Visual System," IEICE Transactions on Fundamentals of Electronics, Communications and Computer Science, Vol. E91, No. 6, pp. 1400-1407, 2008.
  6. C. H. Noh, S. L. Lee, and M. S. Zo, "An effective classification method for TFT-LCD film defect images using intensity distribution and shape analysis," Journal of Korea Multimedia Society, Vol. 13, No. 8, pp. 1115-1127, 2010.
  7. J. H. Kim, and K. W. Ko, "Research on Defect Inspection of LCD Panel," Journal of the Korean Society for Precision Engineering, Vol. 24, No. 4, pp. 7-14, 2007.
  8. C. D. Jung, S. M. Lee, B. J. Yun, J. J. Lee, I. Choi, and K. H. Park, "TFT-LCD Defect Detection Using Mean Difference Between Local Regions Based on Multi-scale Image Reconstruction," Journal of Korea Multimedia Society, Vol. 15, No. 4, pp. 439-448, 2012. https://doi.org/10.9717/kmms.2012.15.4.439
  9. S. M. Lee, T. H. Kim, and K. H. Park, "Sequential defect detection according to defect possibility in TFT-LCD panel image," Journal of Korean Institute of Electronics and information Engineers, Vol. 51 , No. 4, pp. 799-806, 2014. https://doi.org/10.5573/ieie.2014.51.4.123
  10. S. Y. Kim, C. D. Jung, Y. C. Song, and K. H. Park, "Intensity Flow Estimation of Thin Film Transistor Liquid Crystal Display Panel Surface Image Using Multiweighted Morphology Pairs," Japanese Journal of Applied Physics, Vol. 49, Issue 6R, pp. 066601-1-066601-5, 2010. https://doi.org/10.1143/JJAP.49.066601
  11. K. S. Kim and H. H. Choi, "Morphological Filter for Enhancement of Monumental Inscription Image," Conference on the Korea Industrial Systems Research, May, 2001, pp. 311-317.