• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.687-690
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• 2006

Influence of polarizer with different haze value on the optical properties of TFT-LCD TV has been investigated. According to the results, a optimum optical performance can be achieved by using the polarizer with proper haze value.

• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.24-27
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• 2002

Even though the TFT-LCD industry gained enough momentum that has been built up in past 10 years, the industry faces new challenges in order to maintain the 'true mainstream display' position in near future. The technical challenges can be summarized in two fold; one is image quality upgrade for different application area. Cost competitiveness is the other big issue in LCD for the continued leadership position in display industry. In this paper, we describe the technology advancement and the technical challenges in LCD to achieve these goals..

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.219-222
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• 2003

The Capacitor DAC with gamma correction is proposed for TFT-LCD (Liquid Crystal Display) driver application. It is based on two ideas. First, 6bit digital code is converted 8bit digital code by memory circuit (Look Up Table) for gamma correction. second, weighted voltage ratio DAC is proposed for reducing area and power consumption.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.733-738
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• 2006

As the film transistor-liquid crystal display (TFTLCD) panels become larger and provide higher resolution, the propagation delay of row and column lines, the voltage modulation of Vcom, and the response time of liquid crystal affect the display images now more than in the past. It is more important to understand the electrical characteristic of TFT-LCD panels these days. This paper describes the electrical model of a 15-inch XGA ($1024{\times}768$) TFT-LCD panel. The parasitic resistance and capacitance of its panel are obtained by 3D simulation of a sub pixel. The accuracy of these data is verified by the measured values in an actual panel [1]. The developed panel simulation platform, the equivalent circuit of a 15-inch XGA panel, is simulated by HSPICE. The results of simulation are compared with those of experiment, according to changing the width of signal. Especially, the proposed simulation platform for modeling TFTLCD panels can be applied to large size LCD TVs. It can help panel and circuit designers to verify their ideas without making actual panels and circuits.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.27-28
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• 2005

We developed Super IPS mode TFT-LCD TV which have contrast ratio over 800:1. To increase contrast ratio, polarizer film, TFT design and color filter photoresist are investigated. In this report, we describe the basic concept and effectiveness of each item. The application of a newly developed color filter photoresist was the most effective for achieving this high contrast ratio.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2003.10a
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• pp.221-224
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• 2003

Recently, the market share of the thin-film-transistor liquid-crystalline-display (TFT-LCD) is growing rapidly in display device market. The backlight unit is used as a light source of TFT-LCD module. A light-guide is one of several important components of backlight unit. The manufacturing technology and optical system design of the light guide is very sensitive to quality and cost of the TFT-LCD module. In the present study a new manufacturing method which is called as direct surface forming(DSF) has been tested under various conditions. The result of this test, V-groove pattern shows different shapes depends on the temperature of mold surface, contact time of mold and depth of V-groove.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.426-429
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• 2005

The fringe-field switching (FFS) mode associated with a transition from a homogenously aligned to twist deformation require rubbing process. In this devices, $1^o$ of misalignment in an azimuthal direction could cause voltage-dependent transmittance (V-T) to be different from that in a normal area and consequently results in a rubbing mura. According to our studies, the single domain FFS cells are much more sensitive to the rubbing mura than the dual domain FFS cell. Moreover, the FFS cells with negative LC are much more sensitive to the rubbing mura than the FFS cells with positive LC.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.59 no.7
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• pp.1340-1345
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• 2010

FRC(Frame Rate Control) has been applied to the monitor and TV product as part of cost-saving in many flat panel display manufacturers. As FRC can represent the same number of gray scale level with bits of a smaller amount than bits of the input image data, it is widely used. However, FRC causes visual artifacts by using repeatedly pre-designed the FRC unit size of block pattern in display devices. Therefore, this paper analyzes the cause of the visual artifacts. And in order to improve them, it proposed the pattern arrangement of FRC unit blocks through frame rolling method as analytic solution for the first time. So, we could embody causes of FRC noise. Using the proposed structure, more robust pattern to FRC noise will be designed.

• Journal of the Semiconductor & Display Technology
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• v.9 no.4
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• pp.93-97
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• 2010

Fast incipient fault diagnosis is becoming one of the key requirements for economical and optimal process operation management in high-tech industries. Artificial neural networks have been used to detect faults for a number of years and shown to be highly successful in this application area. This paper presents a novel test technique for fault detection and classification for module process of TFT-LCD manufacture using support vector machines (SVMs). In order to evaluate SVMs, this paper examines the performance of the proposed method by comparing it with that of multilayer perception, one of the artificial neural network techniques, based on real benchmarking data.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.45 no.1
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• pp.29-37
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• 2008

With the rapid development of display technology as well as the diversity of display, image quality assessment plays an important role in display color reproduction. The image quality has described by objective evaluation based on the physical measured data, such as contrast ratio, color reproduction range, color temperature, and gamma characteristics, etc., however, the final judgement is achieved by perceptual quality assessment of observers. Therefore, it is necessary to investigate the relationship between physical performance of display and perceptual image quality. Thus, in order to evaluate objectively the color reproduction characteristics of two mobile displays, TFT-LCD and AMOLED, we measured the darkroom contrast ratio of full screen, luminance and color temperature of full-screen white, full-screen gray and color linearity, tone reproduction of color scales for each RGB primary, and color reproduction range. Then the pair-wise comparison is implemented for image experts and naive observers not only to judge their preference on principal evaluation attributes but also to subjectively describe perceived image quality. Through two evaluation processes, we derived the objective bases that can prove the results of subjective image quality assessment by interconnecting physical factors that have influence on observers' preference judgements. Finally, this paper provided important information for improving the image quality and increasing preference from an observer's point of view.