• 한국전기전자재료학회논문지
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• 제17권1호
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• pp.75-82
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• 2004

We have studied the influence of rubbing directions on electro-optic characteristics of the fringe field driven hybrid aligned nematic liquid crystal (LC) cell by computer simulation. When a LC with positive dielectric anisotropy is used, the results show that the driving voltage and transmittance decreases as the rubbing direction with respect to horizontal electric field direction increases. The reason for decrease in light transmission is the increase of tilt angle on the center of common electrode. In this paper, we have studied how the rubbing angle effects on the transmittance of the cell by investigating a distribution of electric field and LC director.

• 한국전기전자재료학회논문지
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• 제17권3호
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• pp.311-318
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• 2004

We have studied electro-optic characteristics as a function of pretilt angle ($\theta$$_{p}$) in the fringe-field switching (FFS) mode using the LC with positive dielectric anisotropy. When $\theta$$_{p}$ is increased from 0$^{\circ}$ to 20$^{\circ}$, a maximum transmittance and an operating voltage are obviously decreased. In the viewing angle characteristics, the cell with low pretilt angle has a wide region for the contrast ratio greater than 5 and has a best luminance uniformity. Therefore, in the FFS device, a low pretilt angle is favored for high transmittance and wide viewing angle.gle.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
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• pp.957-960
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• 2003

We have studied the influence of rubbing directions on electro-optic characteristics of the fringe field driven hybrid aligned nematic liquid crystal (LC) cell by computer simulation. When a LC with positive dielectric anisotropy is used, the results show that the driving voltage and transmittance decreases as the rubbing direction with respect to horizontal electric field direction increases. The reason for decrease in light transmission is the reduction of twist angle and increase of tilt angle on the center of common electrode. In this paper, we have studied how the rubbing angle effects on the transmittance of the cell by investigating a distribution of electric field and LC director.

• Journal of the Optical Society of Korea
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• 제16권2호
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• pp.166-169
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• 2012

We propose a high-transmittance multi-domain vertical alignment liquid crystal device with a protrusion structure. Disclination lines, which inevitably appear at the boundaries of domains in a multi-domain structure, can be reduced by adding a protrusion structure on the top substrate. The transmittance was improved by 11% using the proposed structure with no change of either the dark state or the operating voltage.

• 전력전자학회:학술대회논문집
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• 전력전자학회 2019년도 추계학술대회
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• pp.166-167
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• 2019

Smart windows are used as windows and doors to determine cooling and heating efficiency in the construction field. It's characteristics can increase the energy saving efficiency. In addition, the function of the smart window that can control the light transmittance transmitted from the external environment of the building to the building according to the needs of the user is attracting attention. In this study, a liquid crystal cell capable of controlling light transmittance of 297 × 210 ㎟ was fabricated by using a liquid crystal device as an optical shutter. Analysis of transmittance change according to driving voltage and driving stability according to thermal environment, We confirmed the applicability of building exterior materials as smart windows.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 추계학술대회 논문집
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• pp.358-361
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• 2001

A new photoalignment material PM15CA, poly{N-(phenyl)maleimide-co-3-[4-(pentyloxy) cinnamate]propyl-2-hydroxy-1-methacrylate}, was synthesized and the electro-optical (EO) characteristics in the vertical-aligned (VA) liquid crystal display (LCD) photo-aligned on the photopolymer surface were studied. Excellent voltage-transmittance(V-T) characteristics in the VA-LCD photoaligned with polarized UV exposure of oblique direction on the pohotopolymer surfaces for 1 min can be achieved. The transmittance of the VA-LCD photoaligned on the photopolymer surface decreased with increasing UV exposure time. We suggest that the decrease of transmittance in the VA-LCD photoaligned on the photopolymer surface is attributed to the dissociation of the ester linkage in the photodimerized cinnamate structure with increasing UV exposure time

• 전기전자학회논문지
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• 제23권4호
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• pp.1224-1229
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• 2019

본 연구에서는 블라인드와 같은 스마트 윈도우 응용을 위해 액정 셀을 제작하였고, 광 투과율이 조절되는 시스템을 개발하였다. 액정 셀의 문턱전압은 1.325V였고, 투과율이 10%일 때 전압은 2.370V를 보여 제작된 액정 셀은 저전압으로 구동됨을 나타내었다. 또한, 액정 셀은 30ms 미만의 응답속도와 80℃/10분간 열을 가한 후에도 안정하게 구동되었다. 구동 시스템은 액정 셀의 인가되는 전압을 0.15V에서 3.53V까지 약 0.5V 간격으로 설계하였고, 실제 인가되는 전압에 따라 액정의 광 투과율이 변화됨을 확인하였다. 이러한 결과는 액정 셀이 스마트 윈도우 응용이 가능성이 있음을 시사한다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.295-295
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• 2016

Recently, TCO films with low carrier concentration, high mobility and high work function are proposed beneficial as front electrode in HIT solar cell due to free-carrier absorption in NIR wavelength region and low Schottky barrier height in the front TCO/a-Si:H(p) interface. We report high transmittance and work function zirconium-doped indium tin oxide (ITO:Zr) films with various plasma (Ar/O2 and Ar) conditions. The role of (Ar/O2) plasma was to enhance the work function of the ITO:Zr films whereas the pure Ar plasma based ITO:Zr showed good electrical properties. The RF magnetron sputtered ITO:Zr films with low resistivity and high transmittance were employed as front electrode in HIT solar cells, yield the best performance of 18.15% with an open-circuit voltage of 710 eV and current density of 34.63 mA/cm2. The high work function ITO:Zr films can be used to modify the front barrier height of HIT solar cell.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 춘계학술대회 논문집
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• pp.59-60
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• 2009

The conventional in-plane field driven-vertical alignment display (VA-IPS) shows fast response time but transmittance shows very low and operating voltage is very high. In this paper, we studies electro-optical properties of the novel in-plane field driven vertical alignment device which has two transistors on array part and common electrode on CF substrate with dielectric layer. The device shows fast response time and high transmittance.

• 한국전기전자재료학회논문지
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• 제16권10호
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• pp.914-922
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• 2003

The FFS (fringe-field switching) mode was known to exhibit both a wide viewing angle and high transmittance, especially when using a liquid crystal with negative dielectric anisotropy. We have studied cell gap-dependent electrode-optic characteristics of the FFS mode using the LC with negative dielectric anisotropy. In case of a small cell gap of 2 ${\mu}$m, the transmittance at the center of pixel and common electrodes is relatively low because effect of surface anchoring that holds the LC to the initial state is larger than that in a large cell gap of 4 .urn such that the LCs in those regions cannot rotate enough. However, in case of a large cell gap of 4 .urn, the effect of surface anchoring becomes relatively small so that the LCs at the center of pixel and common electrode can be twisted enough by applied voltage, giving rise to high transmittance. Therefore, we can conclude that the light efficiency is dependent on the cell gap.