• 한국정보디스플레이학회:학술대회논문집
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• 2002.08a
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• pp.943-946
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• 2002

Liquid Crystal Spatial Light Modulators (LC-SLMs) provide many interesting applications in laser optics and opto-electronic systems, in addition to displays. Among them, three topics developed at Thales Research & Technology are reviewed: wavefront correction for laser beam control, microwave processing in radar systems and holography for TN-LCDs viewing angle compensation.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.21-25
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• 2005

In order to implement high pixel density in AMLCDs, high aperture ratio is a very important design factor. We have implemented VGA panels with IPS and TN modes. IPS mode is a very attractive solution to meet the requirement for mobile phone displays. It provides much higher aperture ratio as well as wider viewing angle at extremely high pixel density over 400 ppi.

• Journal of Information Display
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• v.3 no.3
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• pp.24-29
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• 2002

Liquid Crystal Spatial Light Modulators (LC-SLMs) provide many interesting applications in laser optics and opto-el ectronic systems, in addition to displays. Among them, three topics developed at Thales Research & Technology are reviewed: wavefront correction for laser beam control, microwave processing in radar systems and holography for TN-LCDs viewing angle compensation.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.11a
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• pp.506-509
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• 2004

We have investigated the generation of pretilt angle for a nematic liquid crystal (NLC) alignment with in-situ photoalignment method on polyimide (PI) surfaces using thin plastic substrates. The LC aligning capabilities and pretilt angle of the thin plastic substrates by in-situ photoalignment method were better than that of the glass substrate by general photoalignment. Also, the LC pretilt angle increased with increasing heating temperature and exposure time. And EO characteristics of photoaligned TN-LCDs using in-situ photodissociation method on glass substrate and on plastic substrate are also excellent.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1112-1114
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• 2009

In this paper, we have studied manufacturing process for liquid crystal displays (LCDs) using plastic substrates. Because the thermal and dimensional stabilities of plastic substrates are decisive issues, both the process and materials were improved to fit the manufacturing requirements of flexible twisted-nematic (TN) and color super-twisted nematic (CSTN) LCDs. Finally, to broaden the flexible display applications, we take advantage of the unique properties of flexible display to design several innovative products.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.671-674
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• 2006

Due to the stricter requests of the human perception of images, many industrial standards such as TCO'03 have been made to survey the Flat Panel Displays (FPD) nowadays. The angular-dependence luminance uniformity is an important item to evaluate the performance of FPD. In this article, we focus on the above test item base on TCO'03 standard in the case of vertical direction of ${\pm}15^{\circ}$. With controlling the driving voltage toward the liquid crystals of TN-type TFT-LCD, there exists a voltage-driving range which can achieve the value of the $L_{max}/L_{min}$ at ${\pm}15^{\circ}\;{\leq}1.7$ readily. Both experiment and simulation have been well analysis.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.241.2-241.2
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• 2014

We present highly transparent liquid crystal displays (LCDs) using hybrid films based on carbon nanomaterials, metal grid, and indium-tin-oxide (ITO) grid. Carbon based nanomaterials are used as transparent electrodes because of high transmittance. Despite of their high transmittance they have relatively high sheet resistance. To solve this problem, we applied grid and made hybrid conductive films based on carbon nanomaterials. Conventional photolithography processes were used to make a grid pattern of metal and ITO. To fabricate transparent conductive films, carbon nanotube (CNT) ink was spin coated on the grid pattern. The transparency of the conductive film was controlled by shape and size of the grid pattern and the thickness of CNT films. The optical transmittance of CNT-based hybrid films is 92.2% and sheet resistance is also reduced to $168{\Omega}/square$. These substrates were used for the fabrication of typical twisted nematic (TN) LCD cells. From the characteristics of LCD devices such as transmittance, operating voltage, voltage holding ratio our devices were comparable to those of pristine ITO substrates. The result shows that the hybrid conductive films based on carbon nanomaterials could be alternative of ITO for the highly transparent LCDs.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.430-430
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• 2007

In general, polyimides (PIs) are used in liquid crystal displays (LCDs) as alignment layer of liquid crystals (LCs). Up to date, the rubbing alignment technique has been widely used to align liquid crystals on the PI surface, which is suitable for mass-production of LCDs because of its simple process and high productivity. However, this method has some disadvantages. Rubbed PI surfaces include the debris left by the cloth and the generation of electrostatic charges during rubbing process. Therefore, rubbing-free techniques for LC alignment are strongly required in LCD technology. In this experiment, PI was uniformly coated on indium-tin-oxide electrode substrates to form LC alignment layers using a spin-coating method and the PI layers were subsequently imidized at 433 K for 1 h. The thickness of the PI layer was set at 50 nm. The LC alignment layer surfaces were exposed to an $Ar^+$ ion-beam under various ion-beam energies. The antiparallel cells and twisted-nematic (TN) cells for the measurement of pretile angle and electro-optical characteristics were fabricated with the cell gap of 60 and $5\;{\mu}m$, respectively. The LC cells were filled with nematic LC (NLC, MJ001929, Merck) and were assembled. The NLC alignment capability on ion-beam-treated PI was observed using photomicroscope and the pretilt angle of the NLC was measured by the crystal-rotation method at room temperature. Voltage-transmittance (V-T) and response time characteristics of the ion-beam irradiated TN cell were measured by a LCD evaluation system.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.1049-1052
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• 2004

In general, contrary to the CRTs with impulsive emission, liquid crystal displays have motion artifacts such as blurring. ghost image, decrease of dynamic CR(contrast ratio), and stroboscopic motion due to hold type driving method. In this paper, to improve motion picture quality of LCDs. impulsive driving method of black data insertion was applied to the OCB mode which is well known for its fast LC response time and wide viewing angle properties. Subject evaluation was carried out with CRT, TN, SIPS(Super IPS). and impulsive driving OCB. Moving picture image quality near CRT was obtained in impulsive OCB driving mode