• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.1092-1095
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• 2003

A driving mechanism and excellent features for an in-plane switching twisted nematic liquid crystal mode (IT mode) that could possibly improve the viewing-angle and color shift characteristics and the cell gap error tolerance is proposed. .It is important that the surface azimuthal anchoring strength of the liquid crystal cell differs at the upper and lower substrates. Furthermore. as a rubbing-free LCD. amorphously aligned in-plane switching twisted nematic mode (a-IT mode) is also demonstrated.

• Journal of Information Display
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• 제12권1호
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• pp.11-15
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• 2011

An inverse-twisted-nematic (ITN) transflective (TRF) liquid crystal (LC) display, where two imprinted optical films (IOFs) with surface microstructures are embedded was developed. One of the IOFs serves as an in-cell patterned retarder with multioptic axes, and the other behaves as a viewing-angle enhancement film. In the presence of an applied voltage, the surface microstructures on the IOFs provide the spontaneous twist of the LC from a vertically aligned state to a $90^{\circ}$ twisted-nematic (TN) state in the transmissive part, and to a $45^{\circ}$ TN state in the reflective part. The developed ITN TRF LC display exhibits high transmission and reflectance, fast response, and wide-viewing characteristics, along with achromaticity.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2005년도 하계학술대회 논문집 Vol.6
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• pp.76-78
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• 2005

We coupled fluid balance equation and director balance equation from Ericksen-Leslie's continuum theory and observed the motion of Twisted Nematic (TN) Liquid Crystals. We simulated flow velocity distribution and director distribution. We interpreted the dynamic response characteristic caused by the flow. As the result of the simulation, We could see the flow effect. And this flow caused abnormal twist to 4msec in switching off state. We could prove that this abnormal twist is a direct cause of optical bounce phenomenon known well until now with the result of simulation.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 하계학술대회 논문집 Vol.7
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• pp.446-447
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• 2006

We investigated the electro-optic characteristics of a fringe-field driven twisted nematic (TN) display using a LC with negative dielectric anisotropy depending on electrode structures. The fringe-field driven TN mode known to exhibit wide viewing angle and excellent color characteristics over a wide viewing range and high transmittance. However, when the electrode width and distance between them is large enough, the transmittance is lower than the conventional vertical field-driven TN mode. By narrowing the electrode width and distance, the transmittance reaches the same value of the conventional TN mode.

• 대한전자공학회논문지SD
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• 제41권8호
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• pp.59-65
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• 2004

본 논문에서는 IT(In-plane switching foisted nematic) 모드를 기반으로 광 투과 특성을 개선시킨 Pseudo-TN IPS(Pseudo-Twisted Nematic In-Plane Switching) 모드를 새롭게 제안하고 그 광 투과 특성을 분석하였다. PTN-IPS 모드의 경우 개구율을 향상시켜 투과율 면적을 향상시킴으로써 종래의 IT 모드보다 약 25%정도의 높은 광 투과 특성을 나타내었으며, 전압인가에 따른 광 투과율의 변화가 선형적이므로, 광 투과율 조절을 위한 액정의 제어가 IT 모드에 비해 용이함을 확인하였다. 또한, IT 모드에 비해 수평방향 대비비는 약 8%정도 특성이 열화 되었으나 수직 방향에 있어서는 약 20%이상의 특성개선을 확인 할 수 있었다. 이와 더불어, 기존 IT 모드가 가지고 있는 샐 갭에 대한 특성 및 장점을 가지고 있어, 차세대 액정 셀을 개발하는데 유용하게 사용될 것이라 생각된다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 춘계학술대회 논문집 디스플레이 광소자 분야
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• pp.121-123
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• 2002

Fast response characteristics of twisted nematic liquid crystal display (TN-LCD) cell with different nematic liquid crystals (NLCs) and cell gap on a rubbed polyimide (PI) surface were studied. High transmittance and fast response time of the TN-LCD on the rubbed PI surface were achieved by using high birefringence ($\Delta$ n) and low cell gap. It is considered that the transmittance and response time of the TN-LCD on the rubbed PI surface decreased as $\Delta$ nd decrease.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2009년도 하계학술대회 논문집
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• pp.288-288
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• 2009

We have studied polarity effects of dielectric anisotropy effects on electro-optical characteristics of a twisted nematic mode driven by fringe electric field, which has wide viewing angle characteristics. Our device is designed as normally black mode between parallel polarizers. The perfect polarization conversion of incident light, which passes through a polarizer, is achieved, when it passes through the twisted liquid crystal (LC) layer. If an electric field is applied, the LC molecules with a positive (or negative) dielectric anisotropy rotate parallel (or perpendicular) to the horizontal component of a fringe electric field as increasing transmittance. From the calculated results, enhanced transmittance of the fringe field-twisted nematic (FF-TN) mode with positive dielectric anisotropy of + 8.2 can be obtained.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2002년도 하계종합학술대회 논문집(2)
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• pp.267-270
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• 2002

LCD is not very expensive and according to the principle that twisted-nematic LCD can modulate by electric signal, lots of researches been developed about many of theory, methods of design and calculating parameters effectively. In 1999 J. A. Davis et ai. proposed the method of deciding upon extraordinary and ordinary axis direction, which is based on Blazing Effect, inspect into changes of diffraction patterns. But in laboratory, it is difficulty to observe 5th or 6th diffraction pattern, and not clear in mathematical. In this paper, illuminating circular polarized beam been to TN LCD (twisted-nematic LCD), we found extraordinary axis direction with inspecting into maximum intensity distribution appeared in the side of analyzer Using Jones matrix method, we endowed with mathematical propriety.

• 한국전기전자재료학회논문지
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• 제17권5호
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• pp.530-535
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• 2004

We have studied 90$^{\circ}$ twisted nematic mode switching by fringe electric field(F-TN mode) using a liquid crystal (LC) with negative dielectric anisotropy. In the device, two polarizers are parallel each other, electrodes exist only on bottom substrate, and one of rubbing direction is coincident with polarizer axis. Therefore, the cell shows a black state before a voltage is applied. With a bias voltage generating fringe-electric field, the LC twists perpendicular to fringe electric field such that the LCs are almost homogeneously aligned except near the bottom surface since the negative type of the LC is used. Consequently, the new device exhibits much wider viewing angle than that of the conventional TN mode due to in-plane switching and relatively high transmittance since the LC director above whole electrode area aligns parallel to the polarizer axis.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 학술대회 및 기술세미나 논문집 디스플레이 광소자
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• pp.41-42
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• 2006

Carbon nanotubes (CNTs) effects on physical properties of the liquid crystal and twisted nematic (TN) liquid crystal (LC) cells have been investigated. The minute doping of CNTs reduces rotational viscosity of the LC, and thus switching time of the TN cells is improved, especially in grey scale response time. In addition, the dielectric anisotropy and birefringence are not affected by such a small amount of CNT-doping and thus voltage-dependent transmittance remains the same.