• Journal of Information Display
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• v.12 no.1
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• pp.17-21
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• 2011

Aliquid crystal (LC) device switchable between the reflective and transmissive modes without sub-pixel division is proposed. By using dye-doped nematic LCs for the top LC layer, transflective displays with high reflectance were realized. It is expected that the proposed device can be applied to high-reflectance transflective devices for outdoor applications.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.354-357
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• 2001

The residual DC properties in the in-plane switching (IFS) liquid crystal displays(LCDs) which have different concentrations of cynao NLCs and different resistivities of fluorine NLCs were studied. We also propose a new residual DC measurement method, named 'light minimum/maximum method'. We confirmed the precision of residual DC measurement by light minimum/maximum method compared with the flicker minimizing method and found that new measurement method of residual DC is better than that of the conventional flicker minimizing method since the resolution level of measurements is in 0.1V

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.354-357
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• 2001

The residual DC properties in the in-plane switching (IPS) liquid crystal displays(LCDs) which have different concentrations of cynao NLCs and different resistivities of fluorine NLCs were studied. We also propose a new residual DC measurement method, named 'light minimum/maximum method'. We confirmed the precision of residual DC measurement by light minimum/maximum method compared with the flicker minimizing method and found that new measurement method of residual DC is better than that of the conventional flicker minimizing method since the resolution level of measurements is in 0.1 V

• 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.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.17-18
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• 2006

Flat Panel Displays (FPDs) have made a revolution in the display industry. TFT-LCD (Thin Film Transistor Liquid Crystal Display) has been the main player of FPD for last two decades. As the industry continuously develops the technology for better performance with lower cost is constantly demanded where several post LCD technologies are being developed. One of the prime candidates of post LCD technology is AMOLED (Active Matrix Organic Light Emitting Diode) that is considered to be an ideal FPD due to its extraordinary display performance and potentially low cost display structure. This technology has been accepted to small size display applications, such as cellular phone, PDA and PMP, etc. In this paper it is discussed that how this technology can be extended to large size display applications, such as TV. The technical issues and solutions of TFT backplane and color patterning of OLED materials are discussed and proposed

• Korean Journal of Optics and Photonics
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• v.25 no.6
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• pp.301-310
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• 2014

Recently, the fringe-field switching (FFS) mode in liquid crystal displays has been used mainly for high image quality and high-resolution liquid crystal displays (LCDs). In this review paper, the fundamental switching principle of the FFS mode, with its excellence over other LC modes in electro-optic performance, will be described. In addition, the development history, present technical issues, and future of the FFS LCD will be discussed.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.7
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• pp.590-594
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• 2001

The residual DC properties in the in-plane switching (IPS) liquid crystal displays(LCDs) which have different concentrations of cynao NLCs and different resistivities of fluorine NLCs were studied. We also propose a new residual DC measurement method, named 'light minimum/maximum method'. We confirmed the precision of residual DC measurement by light minimum/maximum method compared with the flicker minimizing method and found that new measurement method of residual DC is more accurate than that of the conventional flicker minimizing method since the resolution level of measurements is in 0.1V.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.10
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• pp.908-913
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• 2003

We have performed computer simulation to obtain electro-optic characteristics of reflective hybrid aligned nematic liquid crystal displays (LCDs) driven by fringe field. The results show that the optimal retardation value (dΔn) of the cell is 0.289 ${\mu}$m, which allows for the cell to have a practical cell gap of larger than 3 ${\mu}$m when manufacturing. A reflectance of the dark state is only 0.114 % for an incident light 550 nm. At this condition, the light efficiency of white state reaches 92.7 %. The display with optimized cell parameters shows that the contrast ratio greater than 5 exists over 600 of polar angle in all directions and lower driving voltage than that of fringe-field driven homogeneously aligned reflective LCD.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.16 no.2
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• pp.109-115
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• 2023

In this paper, we demonstrated the orientation characteristics of liquid crystals using UV-treated FSAM as alignment layer. Moreover we confirmed the FSAM properties before and after UV treatment on indium tin oxide (ITO) glass substrates using physicochemical analysis. The hydrophobic property of the FSAM surface is change to hydrophilic through UV treatment. After UV treatment the LC molecules also were uniformly and horizontally aligned on the FSAM surfaces and the pretilt angle was obviously changed 90° degrees to 0° degrees. EO characteristic of TN cell which was fabricated with UV-treated FSAM was faster response time compare to conventional PI layer. The FSAM before and after UV treatment has a superior application potential as the LC alignment layer for LCD, potentially replacing the conventional polyimide layer.

• Journal of the Optical Society of Korea
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• v.18 no.6
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• pp.783-787
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• 2014

This paper presents an improved vertical alignment nematic liquid crystal mode characterized by the protrusions or slits of the top substrate and additional stripe type common electrodes with polarity switching of the bottom substrate to improve multi-domain vertically aligned (MVA) and patterned vertically aligned (PVA) nematic modes. MVA and PVA modes have disadvantages such as an LC disclination in the vicinity of the middle region of electrodes between the top and bottom protrusions in MVA mode or the top and bottom slits in PVA mode. Therefore, the stripe type common electrode generating a horizontal electric field and the protrusion or slit producing some pretilt of liquid crystals (LCs) were used to improve the LC disclination, which influences the transmittance and response speed. The simulation results showed that the proposed VA mode has higher transmittance than the MVA and PVA modes. As a result, the proposed VA mode can improve the response speed and transmittance remarkably, which makes it useful for upgrading the LCD display quality.