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A Fuzzy Search Method for Auto Focusing of CCM Test Handlers

CCM 테스트 핸들러의 자동초점조절을 위한 퍼지탐색 방법

  • 권혁중 (충북대학교 제어계측공학과) ;
  • 윤희상 (충북대학교 제어계측공학과) ;
  • 박태형 (충북대학교 제어계측공학과)
  • Published : 2007.11.01

Abstract

We propose a new-focusing method for test handlers of compact camera module (CCM), The MMD (max-min difference) method is applied to calculate the focus value quickly considering the noisy output of CCM. Also, the fuzzy search method is applied to find the maximum focus value effectively. We design a fuzzy processor to control the lens position by focus values and brightness values, which improves the focusing performance in the sense of speed and processor memory. The proposed method is implemented by computer program and installed at the CCM test handler machines. The simulation results are presented to verify the usefulness of the proposed method.

Keywords

References

  1. 윤희상, 박태형 '소형 카메라 모듈용 테스트 핸들러의 자동 초점 조절 방법,' 제어.자동화.시스템공학 논문지, 제 12 권, 제 2 호, 2006.2 https://doi.org/10.5302/J.ICROS.2006.12.2.168
  2. K. S. Choi, J. S. Lee, and S. J. Ko, 'New autofocus technique using the frequency selective weighted median filter for video cameras,' IEEE trans. on Consumer Electronics, vol. 45, no. 3, pp. 820-827, Aug, 1999 https://doi.org/10.1109/30.793616
  3. T. Koizumi, H. S. Chun, and H. Zen, 'A new optical detector for a high-speed AF control,' IEEE Trans. on Consumer Electronics, vol. 42, no. 4, pp. 1055-1061, Nov, 1996 https://doi.org/10.1109/30.555905
  4. M. Born, E. Wolf, Principles of Optics, Cambridge Univ, Press, 1999
  5. J. He, R. Zhou, and Z. Hong, 'Modified fast climbing search auto-focus algorithm with adaptive step size searching technique for digital camera,' IEEE Trans. on Consumer Electronics, vol. 49, no. 2, May, 2003
  6. T. H. Cormen, C. E. Leiserson, R. L. Rivest, C. Stein, Introduction to Algorithms, MIT Press, 2001
  7. Y. Xiong and S. A. Shafer, 'Depth from focusing and defocusing,' The Robotics Institute Camegie Mellon Univ, Pittsburgh, technical report, 1993
  8. Y. M. Lee, S.-I. Jang, K. W. Chung, D. Y. Lee, W. C. Kim, and C.-W. Lee, 'A fuzzy-control processor for automatic focusing,' IEEE Transactions. on Consumer Electronics, vol. 40, no. 2, May 1994
  9. M. Murakami, N. Honda, 'An exposure control system of video cameras based on fuzzy logic using color information,' IEEE International conference, vol. 3, 8-11 Sept. 1996
  10. R. A. Jarvis, 'Focus optimization criteria for computer image processing,' Microscope, vol. 24, no. 2, pp. 163-180, 1976
  11. S. K. Nayar and Y. Nakagawa, 'Shape from focus,' IEEE Trans. on Pattern Analysis and Machine Intelligence, vol. 16, no. 8, pp. 824-831, Aug, 1994 https://doi.org/10.1109/34.308479
  12. J. H. Lee, K. S. Kim, and B. D. Nam, 'Implementation of a passive automatic focusing algorithm for digital still camera,' IEEE Trans. Consumer Electronics, vol. 41, no. 3, pp.449-454, 1995 https://doi.org/10.1109/30.468047
  13. 신승현, '디지털 카메라를 위한 새로운 자동초점 조절 알고리즘의 연구,' 대한전기학회논문지, 제 50 권, 제 9 호, pp. 447-453, 2001
  14. 지철근, '최신 전기 응용,' 문운당, 2002
  15. 이재형, 이형구, 이용희, 'Programming game Al by example,' 사이텍미디어, pp. 469-515, 2006