• 한국진공학회지
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• 제12권S1호
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• pp.33-35
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• 2003

The electrooptic properties of the reflected light in a reflective mode, $45^{\circ}C$twisted nematic liquid crystal (TNLC) cell were investigated in the voltage regions near and away from the Freedericksz transition threshold. The measured reflectivity away from the threshold voltage ($V_th$) could not be described by the model which assurnes a constant tilt angle as well as a linearized distribution of twist angle across the cell, although the data are well fitted near $V_th$. We found that in the voltage region away from $V_th$, the model considering the distributions of the tilt angle and the twist angle should be applied for the calculation of the reflectivity. The director-axis distributions were obtained from the numerical integration of the Euler-Lagrange equation.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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• pp.502-504
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• 2009

We demonstrate a pixel-isolated bistable twist-splay namatic (PI-BTSN) liquid crystal (LC) cell which has two stable states of splay and ${\pi}$-twist. Each state is stabilized by a multi-dimensional anchoring effect of pixel-isolating polymer walls without any chiral additives. Polymer walls are formed around the pixel region by anisotropic phase separation between LCs and reactive mesogens. Switching between the two states is archived by using vertical and horizontal electric fields. The memory mode of the fabricated LC cell has shown infinity memory time.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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• pp.560-563
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• 2007

The light efficiency of fringe-field switching (FFS) mode was found to be dependent on the magnitude of dielectric anisotropy, indicating that the voltagedependent maximal effective cell retardation value in the on state is a function of magnitude of the dielectric anisotropy of the LC.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2007년도 하계학술대회 논문집 Vol.8
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• pp.396-396
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• 2007

We investigated the liquid crystal (LC) aligning capabilities and electrooptical characteristics of semi-transparent silver paste electrodes substituting indium tin oxide (ITO) electrodes. Experimental results show that a uniform vertical LC alignment and a large pretilt angle were achieved using the semi-transparent silver paste. The vertical alignment mode based on the semi-transparent silver paste electrodes showed appropriate electro-optical characteristics and a high transparency in comparison with that based on the ITO electrodes. These results indicate that the semi-transparent silver paste electrodes of liquid crystal displays could substitute the ITO electrodes.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 춘계학술대회 논문집 디스플레이 광소자 분야
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• pp.114-117
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• 2005

We have fabricated twisted nematic (TN) cell doped by carbon nanotubes (CNTs). The CNTs with a minute amount of doping do not perturb the liquid crystal orientation in the off- and on-state. The hysteresis studies of voltage-dependent transmittance and capacitance under ac and dc electric field show that the amount of residual dc, which is related to image sticking problem in liquid crystal displays, is greatly reduced due to ion trapping by CNTs.

• Journal of the Optical Society of Korea
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• 제19권3호
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• pp.260-264
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• 2015

We propose a negative liquid crystal (n-LC) cell with parallel patterned electrodes for high transmittance and fast response. The proposed cell has higher transmittance and shorter response time than a conventional fringe-field switching cell using n-LCs, because the proposed cell does not have transmittance dips and does have a thinner LC layer.

• 한국위성정보통신학회논문지
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• 제10권2호
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• pp.75-79
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• 2015

본 연구에서는 폴리이미드 박막위에서의 수직 및 수평배향에서 혼합액정의 배향 특성에 대해서 연구하였다. 혼합액정은 러빙을 이용하여 배향처리하였으며, 러빙에 사용된 폴리이미드 박막은 알킬기를 Side Chain으로 가진 수직배향용 배향막과 그렇지 배향막으로 나누어서 프리틸트각 특성을 측정하였다. 실험결과 혼합액정을 사용하여 양호한 배향상태를 얻을 수 있었으며, 고온에서의 열 안정성에서도 우수한 특성을 보이는 것을 알 수 있었다. 또한 프리틸트각의 발생 원리를 이해하기 위해서 접촉각 측정을 실시하였으며, 이 둘이 밀접한 상관관계를 갖고 있음을 알 수 있었다

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.1386-1389
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• 2008

Conventional viewing angle switching electrode requires pixel division and additional liquid crystal panel. Hence the conventional viewing angle switching has low aperture ratio and high thickness. In this paper we proposed new viewing angle switching using hybrid aligned nematic mode by fringe-field electrode field (named HAN-FFS) with single liquid crystal panel. The fringe-field switching electrode is located at the bottom, and the additional common electrode is located at the top of the cell to control viewing angle. The proposed device is free from additional liquid crystal panel and pixel division. Consequently, the suggested structure has not only high aperture ratio but also show an excellent potential for viewing angle switching.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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• pp.1185-1187
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• 2004

We have studied a liquid crystal (LC) mode, named locked super homeotropic (LSH), where the LCs aligned homeotropically are locked by surrounding walls such as cubic, hexagonal and cylinder. In the device, the vertically aligned LCs tilt down symmetrically around the center of the cell when a voltage is applied and thus it exhibits wide viewing angle. In addition, since the LCs is locked in micro domains the LCs do not flow to the bottom of the panel by gravity.

• Transactions on Electrical and Electronic Materials
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• 제4권4호
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• pp.7-9
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• 2003

Viewing angle characteristics of a nematic liquid crystal (NLC) using a in-plane driven (IPD) vertical alignment (VA) cell without a negative compensation film on a homeotropic alignment layer were studied. Good voltage-transmittance (V - T) curves were obtained using the rubbing aligned IPD- VA cell. However, instability and low transmittances of V - T characteristics in photo aligned IPD- VA cell was measured. The EO performance of a rubbingaligned IPD- VA cell without a negative compensation film was wider than that of photoaligned IPD- VA cell and conventional VA cell. Also, the fabrication processes using the rubbing aligned IPD- VA cell mode be carried out with only one-sided rubbing.