The Transactions of The Korean Institute of Electrical Engineers (전기학회논문지)

The Korean Institute of Electrical Engineers (대한전기학회)
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An Effective Auto-Focusing Method for Curved Panel Inspection System

곡면 패널 검사를 위한 효율적인 오토 포커싱 방법

  • Lee, Hwang-Ju (Dept. of Control and Robot Engineering, Chungbuk National University) ;
  • Park, Tae-Hyoung (Dept. of Electronics Engineering, Chungbuk National University)
  • Received : 2016.08.18
  • Accepted : 2017.02.01
  • Published : 2017.04.01
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Abstract

The curved panel is widely used for display of TVs and smart phones. This paper proposes a new auto-focusing method for curved panel inspection system. Since the distance between the camera and the panel varies with the curve position, the camera should change its focus at every inspection time. In order to reduce the focusing time, we propose an effective focusing method that considers the mathematical model of panel curve. The Lagrange polynomial equation is applied to modeling the panel curve. The foci of initial three points are used to get the curve equation, and the other foci are calculated automatically from the curve equation. The experiment result shows that the proposed method can reduce the focusing time.

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References

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