• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.463-465
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• 2006

We have developed the VIC (Viewing-angle Image Control) TFT-LCD, which can change viewing-angle from $80^{\circ}$ to $170^{\circ}$. This display has the same thickness and weight as existing TFT-LCD, because it is made of only single LC cell without additional components. Moreover, we developed ways to protect effectively the displayed information in narrow viewing angle mode.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.905-909
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• 2002

Characteristics of reflective LCDs, which have gained a lot of notice in recent years, rely largely on optical design of circular polarizers and the quarter-wave plates, as a component. Important design includes wavelength dispersion, viewing angle, uniformity of display and matching of refractive index. Our work has contributed to improving performance of reflective LCDs by enhancing the characteristics of polymer film using stretching and optical lamination technologies. To design that offers higher contrast and wider viewing angle, we have discovered that it is necessary to control viewing angle variation of the polarizing axis in order to compensate for the viewing angle of the polarizing film as well as the optical anisotropic properties of liquid crystal. Applying this technology to circular polarizers used for reflective LCDs enables design of wide viewing angle circular polarizers. In order to realize higher contrast for reflective LCDs, it is also necessary to design other optical materials including polarizing films. For design of hybrid optical film, it is particularly necessary to reduce surface reflection and interface reflection. This paper also reports our findings concerning this topic.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.399-402
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• 2007

We propose a method to achieve both wide viewing angle (WVA) and narrow viewing angle (NVA) characteristics with a single liquid crystal (LC) panel and a single backlight system by using 3-terminal electrode structure. We could control the viewing angle of a single LC cell by using the horizontal or vertical alignment of LC for the dark state at the front.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08a
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• pp.545-548
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• 2007

This Viewing angle control of fringe-field switching (FFS)-LCD using only one panel has been investigated. Viewing angle switching cell is composed of main- and sub-pixel, in which the former has a role of image expression and the latter has a role of viewing angle switching.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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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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• 2008.10a
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• pp.1383-1385
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• 2008

In the viewing-angle image control (VIC) technology, one pixel is made up of a quad pixel structure which is consisting of R, G, B, and electrically control briefringence (ECB) sub-pixels. Two types of test stimuli were used; text & complex image respectively. The limitations of those methods were found from the experiment. From the results the advanced GC technology was proposed.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1341-1344
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• 2009

A novel method to control the viewing direction by moving aperture location in 4-f illumination optics to control light direction is proposed. Based on integral imaging principle, the relayed point light sources by 4-f optics are modulated by a spatial light modulator, displaying three-dimensional images. In the proposed method, we locate the aperture, which acts as a band pass filter, around an optic axis to control the light direction. Resultantly, assuming that we know the viewer position by a tracking system, we can display appropriate three-dimensional images over large viewing angle.

• ETRI Journal
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• v.36 no.2
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• pp.232-241
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• 2014

A holographic display system with a 22-inch LCD panel is developed to provide a wide viewing angle and large holographic 3D image. It is realized by steering a narrow viewing window resulting from a very large pixel pitch compared to the wave length of the laser light. Point light sources and a lens array make it possible to arbitrarily control the position of the viewing window for a moving observer. The holographic display provides both eyes of the observer with a holographic 3D image using two vertically placed LCD panels and a beam splitter to support the holographic stereogram.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1308-1311
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• 2009

The authors describe a 360 degree viewing display that can be viewed from any direction. To generate all-around 360 degree viewing window, we developed a sp ecial diffusion screen with one viewing aperture using holographic optical elements.

• Korean Journal of Optics and Photonics
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• v.33 no.2
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• pp.67-73
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• 2022

In a head-mounted display (HMD) for virtual-reality applications, a narrow viewing angle is preferred to the usual, wide viewing angle because the HMD is positioned close in front of the user's eyes, and the display position is fixed. In this paper, we propose a new back-light unit (BLU) for implementing a narrow viewing angle, which is suitable for a HMD. By optimizing the scattering patterns in the light-guide-plate and inverse-prism structures, the viewing angle and correlations between structural parameters in the BLU components are analyzed with ray-tracing simulations. As a result, a double-angle inverse-prism structure incorporating the scattering patterns of a light-guide plate is chosen, which results in a 14% increase in center luminance, a 16% decrease in the vertical viewing angle, and a light efficiency of up to 70%, compared to a conventional BLU. Thus, the new BLU system is expected to be applied in a high-efficiency liquid crystal display.