• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.05a
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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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• 2008.10a
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• pp.348-351
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• 2008

We suggest a viewing angle control mode of liquid crystal display(LCD) with additive thermal controllable optical layer [TCOL], which composed of homeotropically or homogenously well aligned LC layer and patterned hating lines on a substrate. In this system, LCD modes with wide viewing angle characteristics can be used as a main panel.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.1
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• pp.54-57
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• 2001

We have developed a new multidomain vertical-alignment (MVA) mode using a homeotropic photopolymer that provides a wider viewing angle for nematic liquidcrystal (NLC) with negative dielectric anisotropy. Good voltage-transmittance curves for he new MVA cell using the homeotropic photopolymer were observed. The viewing angle of the new MVA cell using the homeotropic photopolymer was wider than that of the conventional VA cell. The wide viewing angle using the new MVA cell is attributable to 4-domain by the ribs with UV exposure on the photopolymer.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.559-562
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• 2003

The effect of pretilt angle on viewing characteristics of an IPS cell is discussed. We calculated optical viewing angle in the IPS cell as function of pretilt angle from $0.5^{\circ}$ to $4^{\circ}$, so that we could confirm that low pretilt angle was profitable for wider viewing property. In order to verify the calculation, we made an IPS cell with very low pretilt angle by the alignment method using ion beam exposure. In the experiment, we confirmed that wider viewing characteristics can be achieved if lower pretilt angle was applied in IPS mode. And Ion beam alignment method was useful for low pretilt creation.

• Journal of the Korean Society of School Health
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• v.26 no.2
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• pp.104-113
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• 2013

Purpose: The aim of this study was to investigate prevalence and ecological characteristics of excessive television viewing among elementary school students in Seoul. Methods: Secondary data, representative sample of 11,082 subjects in Seoul was used. After prevalence of the excessive television viewing was identified by using factor analysis, 6 main factors explaining the ecological indicators was founded. After identifying prevalence of the excessive television viewing, by using factor analysis, we found 6 main factors explaining the ecological indicators. After categorizing factors into socio-psychological and lifestyle characteristics, we were investigated the odds ratio of excessive television viewing per characteristics by using multiple logistic regression. Results: The prevalence of excessive television viewing was 29.7% among the elementary school student in Seoul. The prevalence were higher in male, higher grade, and non-South of the Han River. Socio-psychological indicators which expressed excessive television viewing were annoying or bullying, scolding from teacher, depressed mode, thought for a runaway from home, an experience of diet, and negative body image. Life style indicators were a lower intake of fruit and vegetables, a higher intake of Ramyun and soft drink, a worse life style of hand washing, and wearing safety equipment. Conclusion: Lifestyle of television viewing was the comprehensive results from family, school, and society rather than a personal preference. Therefore, it is necessary to educate the hazard of excessive television viewing, to reenforce the students' health competence, to activate a safe leisure program as an alternate of television viewing, and to develop a recommendation.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.1501-1504
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• 2006

The WV film successfully enlarged the field of view of the TN mode and made TN popular for larger size applications such as PC monitors. The hybrid alignment of the PDM (polymerized discotic material) layer is also suited for the OCB mode, which is promising as a nextgeneration LCD-TV because of fast panel response and a wide viewing angle. This paper describes recent technological progress in WV films, especially for OCB.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.311-314
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• 2003

Holographic diffuser(HD) layer was demonstrated to be located inside LC cell for a transmissive LCD of TFT-array on Color Filter structure. Master pattern of this layer was generated by holographic method and this pattern was replicated by the stamping of the master pattern on UV resin. Combined with a compensation film, TN-mode LCD with this layer showed improved viewing angle characteristics, especially along the up-down direction.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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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.

• Journal of Information Display
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• v.5 no.2
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• pp.39-42
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• 2004

A novel fast-switching LCD with dual-domain bend (DDB) mode is described. DDB alignment is achieved using antiparallel-rubbed cell filled with chiral-doped LC. Initial alignment is mono-domain 180-degree twist. Tilt direction is controlled by oblique electric field to be counter direction in each domain. Twist-to-DDB deformation occurs continuously so that DDB mode does not require high-voltage initialization which is inevitable in Optically Compen sated Bend (OCB) mode. DDB gives wide and symmetric viewing angle in contrast to mono-domain bend formed from 180-degree twist showing strong asymmetry.

• 한국정보디스플레이학회:학술대회논문집
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• 2000.01a
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• pp.47-48
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• 2000

Parameters of a biaxial compensation film and a liquid crystal cell for the optically compensated bend mode LCD with wide viewing angle were optimized. For practical approach, we calculated the optical refractive indices of a retardation film when thickness of a retardation film was fixed at 50 ${\mu}m$. Furthermore, we also optimized optical parameters of LC cell when parameters of a retardation film were different with designed values, because the biaxial compensation film with exact designed values was very difficult to fabricate. In experiments, we achieved the wide viewing angle of over the ${\pm}$ 60 degrees by using a biaxial compensation film with a practical thickness value.