A Study on the Rotation-induced Birefringence in Plastic Disk Substrate

회전에 의한 플라스틱 기판에 야기되는 복굴절의 측정에 관한 연구

  • 김종선 (단국대학교 대학원 기계공학과) ;
  • 윤경환 (단국대학교 기계공학과)
  • Published : 2003.05.01

Abstract

Extensive studies have been conducted for reducing the residual stresses and birefringence in injection-molded optical disk substrate. Flow-induced and thermally-induced stresses and birefringence have been found as two main sources during injection molding process. However, high speed rotation also induces extra stresses and birefringence in real operation of disk drives. In the present paper rotation-induced in-plane birefringence has been measured and presented for CD and DVD substrates at different radial position. About 10 - 15 nm of extra retardation has been measured up to 4,800 rpm.

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