Journal of Institute of Control, Robotics and Systems (제어로봇시스템학회논문지)

Institute of Control, Robotics and Systems (제어로봇시스템학회)
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An Auto-Focusing Method for CCM Test Handlers

소형 카메라 모듈용 테스트 핸들러의 자동 초점 조절 방법

  • 윤희상 (충북대학교 제어계측공학과) ;
  • 박태형 (충북대학교 제어계측공학과)
  • Published : 2006.02.01
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Abstract

This paper proposes an auto-focusing method for production of compact camera module (CCM). The CCM test handlers are mainly used in the final CCM production stage to test and adjust the lens focus of CCMs. To improve the productivity of CCM test handlers, we propose the auto-focusing method adjusting the lens focus efficiently. The max-min-difference (MMD) method is newly developed to compute the focus value efficiently, and two-stage searching method is also developed to find the best focus position quickly. Experimental results are presented to verify the usefulness of proposed method.

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References

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