Improvement of the Optical Characteristics of Vision System for Precision Screws Using Ray Tracing Simulation

광선추적을 이용한 정밀나사 비전검사용 광학계의 결상특성 향상

  • Baek, Soon-Bo (Graduate School of NID Fusion Technology, Seoul Nat'l Univ. Sci. Tech.) ;
  • Lee, Ki-Yean (Graduate School of NID Fusion Technology, Seoul Nat'l Univ. Sci. Tech.) ;
  • Joo, Won-Jong (Mechanical Design and Automation Engineering, Seoul Nat'l Univ. Sci. Tech.) ;
  • Park, Keun (Mechanical Design and Automation Engineering, Seoul Nat'l Univ. Sci. Tech.) ;
  • Ra, Seung-Woo (Research Center, Seoul Metal Co.)
  • 백순보 (서울과학기술대학교 NID 융합기술대학원) ;
  • 이기연 (서울과학기술대학교 NID 융합기술대학원) ;
  • 주원종 (서울과학기술대학교 기계설계.자동화공학부) ;
  • 박근 (서울과학기술대학교 기계설계.자동화공학부) ;
  • 나승우 (서울금속(주) 연구소)
  • Received : 2011.04.01
  • Accepted : 2011.06.18
  • Published : 2011.09.01

Abstract

Recent trends for the miniaturization and weight reduction of portable electronic parts is the use of subminiature components. Assembly of the miniaturized components requires subminiature screws of which pitch sizes are in a micrometer scale. To produce such a subminiature screw with high precision threads, not only a precision forming technology but also high-precision measurement technique is required. In the present work, a vision inspection system is developed to measure the thread profile of a subminiature screw. Optical simulation based on a ray tracing method is used to design and analyze the optical system of the vision inspection apparatus. Through this simulation, optical performance of the developed vision inspection system is optimized. The image processing algorithm for the precision screw inspection is also discussed.

Keywords

References

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