• 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.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.39 no.4
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• pp.10-18
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• 2002

This paper reports a methodology for calculating distribution of the director in an In-plane switching liquid crystal cell by a numerical technique. To calculate distribution of the director, we developed a three dimensional finite element method (FEM) and calculated the distribution of electric potential and electric field in the liquid crystal cell. We have considered the free-energy density composed of electric potential and strain energy in the bulk of liquid crystal cell and calculated the switching property of liquid crystal cell by the Ericksen-Leslie equation and the Laplace equation We generated 1,859 nodes and 8,640 elements for IPS mode cell with 24${\mu}{\textrm}{m}$$\times$12${\mu}{\textrm}{m}$$\times$4.5${\mu}{\textrm}{m}$ and performed transient analysis until 16ms. As a result, horizontal electric field occurred at cell region except liquid crystal region above electrodes and the disclination occured on electrodes.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.3
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• pp.175-180
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• 2016

In this study, we proposed an optical compensation method to improve the symmetricity of contrast ratio for wide viewing angle IPS (in-plane switching) LCD. First, the phase retardation depending on the thickness of compensation film is calculated, and then the phase change is presented at the $Poincar{\acute{e}}$ sphere. The phase retardation and the polarization state of the light passing through the optical elements are caculated by using the EJMM (extended Jones matrix method). In addition, the transmittance and the contrast countour are also calculated by using the Berremann's $4{\times}4$ matrix method. The simulation is carried out for a IPS LC cell with positive A/C/A compensation film. From the standard deviation of the contrast ratio, we confirmed the symmetricity at each viewing angle is inversely proportional to the standard deviation and calculated the optimum design condition of the uniaxial compensation film for the IPS LCD.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.20 no.2
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• pp.167-172
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• 2007

In this paper, we analyzed the molecular behavior of IPS-LCDs and VA-LCDs by using numerical simulation. The numerical simulation was performed on the basis of Ericksen-Leslie continuum theory. To improve the accuracy of the calculation, we considered fluid balance equation and director balance equation at the same time. thus, we calculated the flow effect for both switching on and off states. As the results of simulation, we confirmed abnormal twist in IPS-LCDs and fast molecular behavior in VA-LCDs which could influence response time.

• Proceedings of the Optical Society of Korea Conference
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• 2005.07a
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• pp.148-149
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• 2005

• Transactions on Electrical and Electronic Materials
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• v.4 no.1
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• pp.24-28
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• 2003

We have studied the influence of rubbing angles with respect to in-plane field direction on electro-optic characteristics of in-plane switching (IPS) liquid crystal display. The results show that the threshold voltage increases and the operational voltage decreases as the rubbing angle increases. Further, the total response time and also response times associated with grey-to-grey transitions become fast as the rubbing angle decreases.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.337-338
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• 2008

We have studied electro-optic characteristics of a high performance liquid crystal display using Fringe In-plane field Switching (FIS) mode. The strong electric fields cause more liquid crystals to reorient almost in plane above and between the pixel electrodes. As a result, the operation voltage is lower and transmittance is higher than those of Fringe Field Switching (FFS) and In-Plane Switching (IPS) modes. Apparently, the transmittance depends on voltage applied at the configurations of FIS mode which are proposed. Therefore, we have studied certain length of between electrodes for maximum transmittance and light intensity.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.796-799
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• 2006

We studied the nematic liquid crystal (NLC) alignment capability by the Ion beam (IB) alignment method on a NDLC (Nitrogen doped Diamond Like Carbon) as a C:H thin film, and investigated electro-optical (EO) performances of the IB aligned In plane switching (IPS) cell with NDLC surface. A good LC alignment by IB exposure on a NDLC surface was achieved. Monodomain alignment of the IB aligned IPS cell can be observed. The good electro-optical characteristics of the IB aligned IPS cell was observed with oblique IB exposure on the NDLC as a-C:H thin film for 1min.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07a
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• pp.393-395
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• 2005

Super In Plane Switching (S-IPS) technology is applied for large TFT-LCD panels used in TV applications. It has a lot of advantages in comparison to the alternative, VA technology. S-IPS shows excellent viewing angle properties and fast response time between intermediate gray levels. If the performance parameters which describe the actual visual performance are considered, S-IPS is much more $advantageous.^{1)}$ However, it shows relatively low contrast ratio in diagonal direction compared to viewing angle characteristic in upper/down direction in S-IPS. In order to compensate the relatively low diagonal contrast ratio, Super-IPS applying for optical film developed, but Super-IPS still has the problem of color shift in black $pattern.^{2)}$ So we improved this problem by developing Enhanced Super-IPS.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.664-667
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• 2003

Super In Plane Switching (S-IPS) technology is applied for large TFT-LCD panels used in TV applications. It has a lot of advantages in comparison to the alternative, VA technology. S-IPS shows excellent viewing angle properties and fast response time between intermediate gray levels. If the performance parameters which describe the actual visual performance are considered, S-IPS is much more advantageous.$^{1)}$ However, it shows relatively low contrast ratio in diagonal direction compared to viewing angle characteristic in upper/down direction in S-IPS. In order to compensate the relatively low diagonal contrast ratio, a newly designed optical film was applied and the truly wide view angle of a S-IPS TW(True Wide)-IPS) was achieved. Our newly developed 30-inch TFT-LCD panel reveals TW-IPS that is optimized for TV application