한국광학회지 (Korean Journal of Optics and Photonics)

  • 제21권2호
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  • Pages.69-73
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  • 2010
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  • 1225-6285(pISSN)
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  • 2287-321X(eISSN)
한국광학회 (Optical Society of Korea)
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폴리머 네트워크가 형성된 TN 액정셀의 고속응답 특성

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

  • 진혜정 (부산대학교 전자전기공학부) ;
  • 김기한 (부산대학교 전자전기공학부) ;
  • 백종인 (부산대학교 전자전기공학부) ;
  • 김재창 (부산대학교 전자전기공학부) ;
  • 윤태훈 (부산대학교 전자전기공학부)
  • 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)
  • 투고 : 2010.03.19
  • 심사 : 2010.04.08
  • 발행 : 2010.04.25
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초록

본 논문에서는 광학적으로 비등방성인 폴리머를 이용하여 $90^{\circ}$ TN(Twisted Nematic) 액정셀의 응답시간을 향상시키는 방법을 제안하였다. 액정과 비등방성 폴리머를 일정 비율로 혼합하여 TN 액정셀에 주입한 뒤 UV를 조사하여 폴리머 네트워크를 형성시킴으로써 투과율에 영향을 주지 않고 응답시간을 향상시킬 수 있다. 폴리머 네트워크가 형성되지 않은 TN 액정셀의 turn-off 시간이 16 ms인데 반해 제안된 방법에서는 액정과 비등방성 폴리머의 혼합 비율이 3, 5, 10 wt%로 증가할 때 12, 11, 9 ms로 고속 turn-off가 구현될 수 있다. 또한, turn-off 동작 시 TN 액정셀에서 발생하였던 delay time과 backflow가 폴리머 네트워크의 형성에 의해 크게 개선됨을 확인하였다.

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.

키워드

참고문헌

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피인용 문헌

  1. Fabrication of a Liquid Crystal Cell Using ITO-deposited Polarizers as Substrates vol.22, pp.2, 2011, https://doi.org/10.3807/KJOP.2011.22.2.090