Journal of the Korean Society of Manufacturing Process Engineers (한국기계가공학회지)

The Korean Society of Manufacturing Process Engineers (한국기계가공학회)
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Reduction of Birefringence and Weld-Line using Over-Flow in Injection Compression Molding for Optic Lens

광학렌즈의 사출압축성형에서 오버플로우를 이용한 웰드라인과 복굴절 저감

  • Kong, Ki-Hwan (Dept. of Mechanical Engineering, Gyeongnam National Univ. of Sci. and Tech.) ;
  • Lee, Jin-Hyo (Dept. of Mechanical Engineering, Gyeongnam National Univ. of Sci. and Tech.) ;
  • Kang, Byung-Ook (Dept. of Mechanical Engineering, Gyeongnam National Univ. of Sci. and Tech.) ;
  • Kwak, Tae-Soo (Dept. of Mechanical Engineering, Gyeongnam National Univ. of Sci. and Tech.)
  • 공기환 (경남과학기술대학교 기계공학과) ;
  • 이진효 (경남과학기술대학교 기계공학과) ;
  • 강병욱 (경남과학기술대학교 기계공학과) ;
  • 곽태수 (경남과학기술대학교 기계공학과)
  • Received : 2018.01.13
  • Accepted : 2018.01.31
  • Published : 2018.02.28
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Abstract

This study has focused on the weld-line and birefringence reduction of a plastic optic lens using over and CAE analysis in injection compression molding. A concave lens, which has a thin thickness in the center and a large difference in thickness between the center and the periphery, often causes weld-line defects during injection molding. CAE analysis has been applied to optimize the overflow design in order to reduce the weld-line defects and the polarization defects. To reduce the weld line and birefringence defects, overflow design and application using CAE analysis show that the measured birefringence values of the specimens before the overflow application were 46.8nm and 36.9nm, and the values after the over-flow application were 13.6nm and 14.0nm. From the experimental results, it is confirmed that birefringence is greatly improved when overflow is applied.

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References

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