Journal of the Korean Institute of Electrical and Electronic Material Engineers (한국전기전자재료학회논문지)

The Korean Institute of Electrical and Electronic Material Engineers (한국전기전자재료학회)
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Study on Electro-optic Characteristics and Dynamic Stability Depending on the Pretilt Angle for the Twisted Nematic(TN) and Fringe-field Switching(FFS) Mode

TN 모드와 FFS 모드에서 Pretilt Angle이 전기 광학 특성 및 동력학 안정성에 미치는 영향에 관한 연구

  • 김미숙 (전북대학교 신소재공학부, BOE-HYDIS TECHNOLOGY 개발 8그룹) ;
  • 정연학 (BOE-HYDIS TECHNOLOGY 개발 8그룹) ;
  • 김향율 (전북대학교 신소재공학부, BOE-HYDIS TECHNOLOGY 개발 8그룹) ;
  • 김서윤 (BOE-HYDIS TECHNOLOGY 개발 8그룹) ;
  • 이승희 (전북대학교 신소재공학부)
  • Published : 2004.11.01
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Abstract

We studied on the electro-optic characteristics and dynamic stability according to an undesirably defined pretilt angle induced in high step coverage of pixel area for the Twisted Nematic (TN) / Fringe-Field Switching (FFS) mode. In case of the TN mode, LC directors twist reversely near the edges of thin-film-transistor and black matrix where the pretilt angle of the LC is not well defined. Therefore, the voltage-dependent dynamics of the LC in TN mode is unstable and shows the bad electro-optic characteristics. On the other hand, in case of the FFS mode, the LCs are twisted parallel to the bottom substrate by fringe electric field and the electro-optic characteristic is not influenced by the pretilt angle of the LC which is not well defined.

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References

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