Transactions of Materials Processing (소성∙가공)

The Korean Society for Technology of Plasticity and materials processing (한국소성∙가공학회)
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An Experimental Study on the Replication Ratio of Micro Patterns of 7 inch LGP using Injection/Compression and RHCM

사출/압축 및 RHCM 기술이 7인치 도광판 마이크로 패턴 전사성에 미치는 영향에 대한 실험적 연구

  • 조성우 (단국대학교 대학원 기계공학과) ;
  • 김종선 (한국생산기술연구원) ;
  • 황철진 (한국생산기술연구원) ;
  • 윤경환 (단국대학교 대학원 기계공학과) ;
  • 강정진 (한국생산기술연구원 융합생산기술연구그룹)
  • Received : 2010.12.27
  • Accepted : 2011.01.12
  • Published : 2011.02.01
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Abstract

Recently, according to the rapid development of display, many display applications, such as, cellular phone, navigation, monitor and LCD TV have been changed from CRT type to LCD type. BLU(Back Light Unit) is one of main parts in LCD unit and generally, it consists of a light source, a reflective sheet, a LGP(Light Guide Plate), a diffuser sheet, and two prism sheets. The most important component of BLU is a light guide plate, which diffuses the input light to the TFT-LCD module uniformly. The LGP is usually made by injection molding process, and it has numerous optical micro patterns on the surface. In the present study the micro-patterned stamper which has cylindrical shape was fabricated by using the UV-LiGA process. And the replication characteristics have been compared among three different kinds of injection molding process; general injection molding, injection/compression molding and RHCM(Rapid Heating and Cooling Molding). Average replication ratios of CIM and ICM were 19.1% and 64.6%, respectively. On the other hand, the average replication ratio of RHCM process showed the higher value of 98.4% among these. It show that maintaining the mold surface above $T_g$ could increase the replication ratio of micro patterns substantially.

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References

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