• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
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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.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2010년도 하계학술대회 논문집
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• pp.173-173
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• 2010

We proposed viewing angle switchable liquid crystal display(LCD) associated with fringe-field switching (FFS) mode with high aperture ratio characteristic. In the device, single pixel is separated into two regions, named as main pixel for displaying images and sub pixel for viewing angle control. In sub pixel region, add the common electrode on the top substrate and the initial alignment of liquid crystal is Hybrid Alignment Nematic (HAN) state. In conclusion, we suggested that the device has high aperture ratio characteristic because the LC directors are rotated in which viewing angle control region are generated fringe electric field.

• Journal of Information Display
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• 제12권2호
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• pp.101-107
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• 2011

To come up with a bistable liquid crystal (LC) device using unpolarized UV light, single-step laser patterning on a photoalignment layer using a photomask was proposed to achieve an equilibrium configuration of LC molecules in contact with a periodically patterned substrate. The patterns were formed by stripes of alternating random planar and homeotropic anchoring on a submicrometer scale in the order of $0.5{\mu}m$. Two possible configurations of bistable LC cells that can be obtained by combining a micropatterned surface formed with alternating random-planar- and homeotropic-alignment with planar- or homeotropic-alignment surfaces were proposed. The alignment properties of the two proposed models were investigated, along with the microscopic switching behavior of micropatterned nematic LC cells.

• Journal of the Optical Society of Korea
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• 제18권3호
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• pp.251-255
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• 2014

A fiber diffuser sheet based on poly (ethylene naphthalate) (PEN) and poly (methylpentene) (PMP) has shown potential for liquid crystal display backlight units, but these materials have an interfacial adhesion problem. To improve the interfacial adhesion between the fibers and matrix components, we have proposed the use of amorphous poly (cyclohexane-1,4-dimethylene terephthalate) (Tritan) instead of PEN. Furthermore, the fabrication processes have been optimized and simplified to improve the optical and mechanical properties of the sheet. As a result, the most effective fiber content for achieving the best haze characteristics of a sample consisting of Tritan and PMP has been identified.

• 한국전기전자재료학회논문지
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• 제35권6호
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• pp.562-567
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• 2022

Novel self-illuminated smart windows were fabricated consisting of Cu-doped ZnS (ZnS:Cu) powder and polymer-dispersed liquid crystal (PDLC). This smart window shows not only switchable transparency but also self-illumination without any attachable luminous body. Its electro-optical characteristics, transmittance, and luminance were investigated in relation to various applied voltages and composition ratios. The optical transmittance and luminous intensity increased with increasing applied voltages. However, the optical transmittance decreased with increasing ZnS:Cu powder content. One of the self-illuminated smart windows, which was fabricated with 9 wt% of ZnS:Cu, achieved the optical transmittance of 60.5% (at 550 nm) and the luminance of 11.0 cd/m² at 100 V. This smart window could be used as a normal switchable smart window in daytime and light-emitting signage at night.

• 한국정보전자통신기술학회논문지
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• 제16권2호
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• pp.109-115
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• 2023

본 논문은 UV(ultraviolet) 처리된 자기 조립 단분자막(fluorinated self-assembled monolayers; FSAM)을 배향막으로 사용한 액정의 배향 특성을 분석하였다. 물리화학적 분석을 사용하여 UV 처리 전후의 ITO(indium-tin-oxide) 유리 기판의 FSAM 특성을 확인하였다. FSAM 표면은 UV 처리에 의해 소수성에서 친수성으로 변화하였다. LC(liquid crystal) 분자는 UV 처리된 FSAM 표면에서 수평방향으로 정렬되었고 선경사각도 90°에서 0°로 변화하였다. UV 처리된 FSAM을 배향막으로 사용하여 제작된 TN(twist nematic) 셀의 전기광학(electro optics; EO) 특성은 기존의 PI(polyimide) 배향막에 비해 응답 시간이 빠른 것을 확인하였다. 이는 UV 처리된 FSAM 이 LCD(liquid crystal display)의 기존 폴리이미드 배향막을 대체할 잠재적인 가능성을 가진다.

• Bulletin of the Korean Chemical Society
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• 제32권12호
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• pp.4377-4381
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• 2011

In this study, real-time and label-free methods for monitoring the enzymatic reaction of urease, which releases ammonia through the hydrolysis of urea in an aqueous solution, were developed using a liquid crystal (LC)-based pH sensor. Nematic liquid crystal 4-cyano-4'-pentylbiphenyl (5CB), doped with 4'-pentyl-biphenyl-4-carboxylic acid (PBA), exhibited a shift in optical appearance from bright to dark when it was in contact with ammonia generated from the enzymatic reaction between urease and urea. This optical change was attributed to the anchoring transitions of LCs caused by hydrophobic interactions between the tails of deprotonted PBA ($PBA^-$) molecules and the LCs at the aqueous/LC interface. This novel technique holds great promise for the sensitive detection of urease along with its substrates and inhibitors.

• 한국응용과학기술학회지
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• 제35권4호
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• pp.1478-1486
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• 2018

Liquid crystals offer plenty of useful activities as improving the stability of emulsion, increasing moisturizing power, drug release, improving skin feeling and visual effect for cosmetics fields. In order to prepare stable semi-transparent gel emulsion, liquid crystal emulsification method was used. The emulsion stabilities of systems containing glycerin, fatty alcohols, surfactants, water and oil were investigated at various temperatures as time passed. The stabilities of all emulsions were evaluated by means of a polarizing microscope, SEM, rheometer, colorimeter and DSC. Even though the samples stored at $50^{\circ}C$ thermostatic chamber were occurred the reduction of hardness, turbidity and ${\Delta}H$ and the peak shift, the semi-transparent gel emulsion was very stable without separation between water and oils phase in emulsion.

• 한국응용과학기술학회지
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• 제14권3호
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• pp.23-28
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• 1997

N-도데카노닐-N-메틸 아미도 폴리올 카르복시알킬 에테르(DGC)/N-도데카노실-N-알킬글루카민(DG)/물 혼합계에서의 상도를 편광현미경, 시차주사열량계(DSC) 및 레올로지를 이용하여 관찰하였다. 편광현미경으로 계면활성제 농도와 온도의 함수로써 얻어지는 액정상의 형태를 관찰할 수 있었고, DSC측정에 의해서는 비등방성 액정과 등방성 액체 사이의 상전이를 관찰할 수 있었다. 헥사고날과 라멜라 액정상 사이에서 레올로지에 의해 측정된 계면활성제 수용액의 점탄성은 편광현미경과 시차주사열량계에서 얻은 결과와 일치됨을 확인할 수 있었다. DGC/DG(5:5 몰비)/물계의 상에 대하여 조사한 결과, 25${\sim}$65wt% 사이에서는 큐빅 액정상, 70wt% 이상에서는 라멜라 액정상이 나타남을 알 수 있었다.

• Bulletin of the Korean Chemical Society
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• 제30권4호
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• pp.935-937
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• 2009