An Optical Configuration for the Normally Black Twisted Nematic Liquid Crystal Cell

꼬인 네마틱 액정 셀의 Normally Black 모드 광학설계

  • 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)
  • 김기한 (부산대학교 전자전기통신공학부) ;
  • 백종인 (부산대학교 전자전기통신공학부) ;
  • 김재창 (부산대학교 전자전기통신공학부) ;
  • 윤태훈 (부산대학교 전자전기통신공학부)
  • Published : 2008.02.29


We propose an optical configuration to compensate dispersion characteristics in the dark state of normally black twisted nematic (NB-TN) liquid crystal display (LCD). We employed a half-wave plate (HWP) and a +A plate to achieve the superior dark state. By using the parameter space diagram (PSD) method, we could obtain the optimum values of parameters and the high contrast-ratio over 500 : 1 could be obtained. Furthermore, excellent dispersion characteristics were also obtained in the bright state. We could confirm the performance of the proposed structure using both the numerical calculations and the experiments.


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