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Fast Switching of a Polymer-networked Twisted Nematic Liquid Crystal Cell

폴리머 네트워크가 형성된 TN 액정셀의 고속응답 특성

  • Jin, Hye-Jung (School of Electrical Engineering, Pusan National University) ;
  • Kim, Ki-Han (School of Electrical Engineering, Pusan National University) ;
  • Baek, Jong-In (School of Electrical Engineering, Pusan National University) ;
  • Kim, Jae-Chang (School of Electrical Engineering, Pusan National University) ;
  • Yoon, Tae-Hoon (School of Electrical Engineering, Pusan National University)
  • 진혜정 (부산대학교 전자전기공학부) ;
  • 김기한 (부산대학교 전자전기공학부) ;
  • 백종인 (부산대학교 전자전기공학부) ;
  • 김재창 (부산대학교 전자전기공학부) ;
  • 윤태훈 (부산대학교 전자전기공학부)
  • Received : 2010.03.19
  • Accepted : 2010.04.08
  • Published : 2010.04.25

Abstract

We propose a method to enhance the response time of a twisted nematic liquid crystal (TN-LC) cell using an anisotropic polymer. Polymer networks are formed by the phase separation between a LC and a UV-curable polymer. A TN-LC cell is exposed to UV light after the mixture of LC and anisotropic polymer is injected into the TN-LC cell. As a result, turn-off time of a TN-LC cell can be decreased remarkably without any loss of the transmittance. The turn-off time of a TN-LC cell with pure LC was 16 ms, but those of polymer networked TN-LC cells were 12, 11, and 9 ms when the concentration of the polymer was 3, 5, and 10 wt%, respectively. Moreover, by virtue of the polymer network, the backflow effect and the delay time generated during the turn-off process disappeared.

Acknowledgement

Supported by : 부산대학교

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