• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.449-450
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• 2005

Alignment characteristic of liquid crystal (LC) on in-cell retarder which is composed of reactive mesogens has been tested. The in-cell retarder which is polymerized on top of the homogeneous alignment layer (AL) has an optic axis along the rubbing direction of the homeogenous AL and does show good alignment effect of the LC without showing any defects, which possibly allows a skip of another AL on the in-cell retarder that was required conventionally to control alignment of the LC. However, the measured pretilt angle is only 0.04 degree so that disclination lines are generated for a cell that uses the in-cell retarder as an AL when the LC is tilted upward by a vertical electric field.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.5
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• pp.427-431
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• 2006

We have studied electro-optic characteristics of reflective $45^{\circ}$ twisted nematic liquid crystal display which implement the new LC orientation using of in-cell retarder film. For the embodiment of reflective liquid crystal display, essentially the optic compensation films was always needed and attached to the outside of glass substrate. In our study, these optic compensation film were not employed in reflective LC cell. On other hand we have employed the in-cell retarder to substitute the optic compensation film and were able to orient the LC molecules using this in-cell retarder. So we have developed the reflective LC cell that has good optical performances without any additional coating process on the in-cell retarder.

• 한국정보디스플레이학회:학술대회논문집
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• 2008.10a
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• pp.773-775
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• 2008

We have developed new in-cell retarder materials that provide good transmittance and resolution with the goal of enhancing the properties of transflective IPS-LCDs. We explored various additive surfactants to optimize the applicability of the materials. Moreover, we selected photopolymerization initiators and liquid crystal diacrylate monomers as negative-type photo-patternable retarder materials, seeking to improve resolution and transmittance.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.1519-1524
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• 2006

We report on new transflective liquid crystal displays (LCDs) having a single cell gap and a single LC mode combined with an inner-patterned retarder. In a vertically or planarly aligned configuration the brightness is greatly improved and a single driving scheme can be employed.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.435-436
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• 2007

In general, Single gap transflective FFS display has an in-cell retarder (ICR) between reflective electrode and liquid crystal (LC) layer. Therefore, Operating voltage is highly increased due to this thick dielectric material. But, we also knew the phenomenon that the increasing rate of Vop is different whether the 1st common electrode was composed of plate type or slit type. In this paper, the common electrode in transmissive part was composed of slit type which had less steepness effect of the V op and in reflective part was composed of plate type. The rubbing angle of reflective part can be adjusted properly to match the voltage dependent transmittance and reflectance.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.12
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• pp.1068-1071
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• 2007

When a dielectric layer, in-cell retarder (ICR) is formed between electrode and LC layer to get a single gap transflective fringe-field switching (FFS) display, the operating voltage ($V_{op}$) is highly increased due to the thickness of dielectric material. But, we also knew the phenomenon that the increasing rate of Vop is different whether the 1st common electrode was composed of plate type or slit type. In this paper, the common electrode in transmissive part was composed of slit type which had less steepness effect of the Vop and in reflective part was composed of plate type. The rubbing angle of reflective part can be adjusted properly to match the voltage dependent transmittance and reflectance.

• 한국정보디스플레이학회:학술대회논문집
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• 2009.10a
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• pp.1361-1362
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• 2009

We challenge to use reactive mesogen optical elements which can be coated inside LC cell. The reactive mesogens as retarder barrier requirements can be achieved between a high performance 2D mode and a low cross talk stereoscopic 3D mode. The fabrication of a 10.1" diagonal LCD which co-operates with a polarizer to from a parallax barrier, is described. In addition, the parallax barrier of reactive mesogens can easily control in mass production and can thus be coated as extremely LC cell, significantly reducing the thickness of LCD. Finally, we have successed to design a switchable 2D/3D displays using reactive mesogen optical elements which can be achieved 3D displays within glasses.

• Journal of Information Display
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• v.12 no.1
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• pp.11-15
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• 2011

An inverse-twisted-nematic (ITN) transflective (TRF) liquid crystal (LC) display, where two imprinted optical films (IOFs) with surface microstructures are embedded was developed. One of the IOFs serves as an in-cell patterned retarder with multioptic axes, and the other behaves as a viewing-angle enhancement film. In the presence of an applied voltage, the surface microstructures on the IOFs provide the spontaneous twist of the LC from a vertically aligned state to a $90^{\circ}$ twisted-nematic (TN) state in the transmissive part, and to a $45^{\circ}$ TN state in the reflective part. The developed ITN TRF LC display exhibits high transmission and reflectance, fast response, and wide-viewing characteristics, along with achromaticity.

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.1179-1181
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• 2004

We have studied a single gap transflective liquid crystal display (LCD) associated with in-plane switching (IPS) mode. In the transmissive IPS cell, the transmittance of electrodes and above electrodes is different, that is, the degree of rotation of the LC director between electrodes and above electrodes is 45 $^{\circ}$ and 22.5 $^{\circ}$ , respectively. Utilizing the different rotating angle of the LC director and in-cell retarder with a quarter-wave plate used below the LC layer, the IPS transflective LCD is realized such that the area between electrodes is used as a transmissive part and the area above electrodes is used as a reflective part.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.05a
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• pp.54-57
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• 2005

We have designed a single gap transflective liquid crystal display (LCD) driven by a fringe electric field, in which the +LC (${\Delta}{\varepsilon}$=7.4, rubbing angle= $80^{\circ}$) is homogeneously aligned in the initial state. This device is a problem that the voltage-dependent transmittance and reflectance curves do not match each other. Thus a dual driving circuit is required. This study shows that optimization of the rubbing angle in the transmissive and reflective regions solves this problem so that the transflective display with a single cell gap and single gamma curve for reflective and transmissive region is possible.