Developement of a System for Glass Thickness Measurement

비접촉 유리 두께 측정 장치 개발

  • 박재범 (충북대학교 대학원 기계공학부) ;
  • 이응석 (충북대학교 기계공학부) ;
  • 이민기 (충북대학교 대학원 기계공학부) ;
  • 이종근 (충북대학교 대학원 기계공학부)
  • Published : 2009.05.01


This paper describes a measuring device of glass thickness using machine vision and image processing techniques on real-time. Today, the machine vision enable to inspect fast and exactly than human's eyes. The presented system has advantages of continuous measurement, flexibility and good accuracy. The system consists of a laser diode, a CCD camera with PC. The camera located on the opposite side of the incident beam measures the distance between two reflected laser beams from the glass top and bottom surface. We apply a binary algorithm to convert and analyze the image from camera to PC. Laser point coordination by border tracing algorithm is used to find the center of beam circle. The measured result was compared with micrometer and showed 0.002mm accuracy. Finally, the errors were discussed how to minimize the influence of glass wedge angle and angular error of moving stage.


Machine Vision;Snell's Law;Glass Thickness


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