• Journal of the Optical Society of Korea
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• 제20권4호
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• pp.510-514
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• 2016

The conventional liquid crystal displays (LCDs) have been using optically uniaxial liquid crystal (LC) medium and this often causes a significant image change at oblique viewing angles. We simulated the viewing angle properties of the biaxial nematic (N_b) phase of a bent-core liquid crystal (BLC) and compared the results with the vertically aligned (VA)- and the in-plane switching (IPS)-LCDs. The N_b phase of the BLC showed a smaller transmittance at the dark state as well as a greater contrast ratio at wide viewing angle. The viewing angle property of the N_b-mode without any compensation film was slightly superior to the IPS-mode with the compensation films eliminating the decross of the polarizers at oblique viewing angle.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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• pp.292-294
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• 2008

We have developed new reflective LCD for Mixed twist nematic LC mode with high quality image. We have found out an optimal twist angle of LC and optical film's axis by simulation. Also we measured electro-optic characteristics for new design panel. As a result, high reflectance and wide viewing angle characteristics were achieved.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2006년도 6th International Meeting on Information Display
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• pp.800-802
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• 2006

A simple wide-viewing-angle solution of electrically controlled birefringence (ECB) LCD is proposed, which is based on a single discotic compensation film. The use of a single discotic film instead of two leads to a considerable reduction in cost while high performance is maintained.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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• pp.452-455
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• 2002

We demonstrate the wide-viewing characteristics of a twisted nematic liquid crystal display (LCD) with self-formed micro-domains through the topographical alignment and fringe field effects of dielectric surface gratings (DSG). The mutual optical compensation between micro-domains within each pixel eliminates the contrast inversion phenomenon of TN mode without complex surface treatments.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2000년도 제1회 학술대회 논문집
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• pp.1-4
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• 2000

We have developed a high performance vertical alignment TFT-LCD, that shows a high light transmittance, and wide viewing angle characteristics with an unusually high contrast ratio. In order to optimize the electro-optical properties we have studied the effect of cell parameters, multi-domain structure and retardation film compensation. With the optimized cell parameters and process conditions, we have achieved a 24" wide UXGA TFT-LCD monitor (16:10 aspect ratio 1920X1200) showing a contrast ratio over 500:1, panel transmittance near 4.5%, response time near 27 ms, and viewing angle higher than 80 degree in all directions.

• Journal of Information Display
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• 제9권2호
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• pp.22-27
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• 2008

We propose an optical configuration of a vertical alignment (VA) liquid crystal (LC) cell to eliminate the light leakage in the diagonal direction. VA LC cell has an excellent contrast ratio in the normal direction due to the no phase-retardation. However, change of the phase-retardation occurs in all directions, which causes the light leakage and deteriorates the characteristics of the dark state. We designed the LC cell structure composed of multiple combinations with two A-plates and two C-plates in order to achieve wide viewing property on the Poincare sphere. From calculations, we show that the proposed structure can improve the viewing angle characteristics by compensating for the light leakage in all directions.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 춘계학술대회 논문집 디스플레이 광소자분야
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• pp.146-149
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• 2004

We have studied a liquid crystal (LC) mode (named locked super homeotropic (LSH)) in which 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. The structure of this LSH mode is suitable for large-sized display panels. since the LCs are locked in micro domains the LCs do not flow to the bottom of the panel by gravity. This mode is applicable to achieve high performance TFT-LCD TV because of high performance characteristics such as high contrast, high brightness, wide-viewing angle.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2000년도 제1회 학술대회 논문집
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• pp.161-162
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• 2000

We propose multi-layer aspheric lenticular lens for rear projection screen to provide wide viewing angle. Each pitch of lenticular lens sheet is divided by three region and image light from projection optical system is propagated widely on each region due to different focal point. Besides, to improve vertical viewing angle of screen, we propose glass bead embedded screen on observer side of lenticular lens.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2005년도 추계종합학술대회
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• pp.853-856
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• 2005

we proposed the optimized conditions of the uniaxial and biaxial compensation films to suppress the light leakage to improve viewing angle characteristics. Compared with conventional OCB mode, the maximum transmittance is increased about 30% and the minimum transmittance is slightly decreased. From here results, we can about OCB mode with wide viewing angle and high contrast ratio.

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2003년도 International Meeting on Information Display
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• pp.608-610
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• 2003

In the paper, we have investigated the reflective cholesteric display based on the polymer stabilization. The bistability in the polymer stabilized cholesteric texture(PSCT) films was observed and wider viewing angle was achieved due to imperfect planar texture.