• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 춘계학술대회 논문집 디스플레이 광소자 분야
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• pp.181-184
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• 2000

A new photo-alignment material, copoly (PM4Ch-ChMA), copoly (poly (4-methacryloyloxy) chalcone-chalconemethacryl) was synthesized and the electro-optical (EO) characteristics for the photo-aligned vertically aligned (VA)-LC display (LCD) were investigated. The monodomain alignment of the NLC for the photo-aligned VA-LCD by linearly polarized UV exposure on the photo-dimerized copoly (PM4Ch-ChMA) surfaces was observed. Excellent voltage-transmittance characteristics for the photo-aligned VA-LCD by UV exposure for 1 min. on the copoly (PM4Ch-ChMA) surfaces were achieved. The response time of the photo-aligned VA-LCD by UV exposure on for 1 min. the copoly (PM4Ch-ChMA) surfaces was about 39.3 ms. The response time for the photo-aligned VA-LCD decreased with increasing UV exposure time.

• Transactions on Electrical and Electronic Materials
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• 제1권3호
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• pp.10-13
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• 2000

In this study the new photo-alignment material copoly(PM4Ch-ChMa)(copoly (poly (4-methancryloyloxy)chalcone-cholesteryl methacry late)) was synthesized, Also, the liquid crystal (LC) aligning capabilities and the electro-optical(EO) characteristics for the photo-aligned vertical-aligned(VA)-LC display(LCD) were studied. The monodomain alignment of the NLC for the photo-aligned VA-LCD by linearly polarized UB exposure on the Photo-dimerized copoly(PM4Ch-ChMA) surface was observed,. Excellent Voltage-transmittance characteristics for the VA-LCD photo-aligned by polarized UV exposure on the copoly (PM4Ch-ChMA) surfaces for 1 min was achieved. The response time of the VA-LCD photo-aligned by polarized UV exposure on the copoly (PM4Ch-ChMA) surfaces for 1 min was 39.3 ms, We suggest that the photo-dimerized chacone group increased with increasing UV exposure time, which then contributes to a low response time of the photo-aligned VA-LCD on the copoly (PM4Ch-ChMA) surfaces.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 D
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• pp.1765-1767
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• 1999

We synthesised a photo-alignment material of PM4Ch (poly(4-methacryloylloxychalcone)). The electro-optical (EO) characteristics of photo-aligned twisted nematic (TN)-liquid crystal display (LCD) with linearly polarized ultraviolet (UV) light irradiation on PM4Ch surface were investigated. The uniform alignment of NLC with polarized UV light irradiation on PM4Ch surface was measured. Also, We had The excellent voltage-transmittance characteristics of photo-aligned TN-LCD. The low threshold voltage of photo-aligned TN-LCD was measured. Moreover, the fast response time of photo-aligned TN-LCD on PM4Ch was successfully achieved. Finally The reduction DC voltage of photo-aligned TN-LCD decreases with increasing the UV light irradiation time on photo-dimerized PM4Ch surface.

• Journal of Information Display
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• 제6권1호
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• pp.8-11
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• 2005

A flexible reflective cholesteric liquid crystal display (ChLCD) is fabricated on plastic substrates by using the pixel isolation method. The polymer walls between pixels and the polymer layers in the pixels are formed by two-step UV irradiation. Electro-optical response of the ChLCD with polymer wall and layer is studied and compared with conventional bistable ChLCD cells.

• Journal of the Optical Society of Korea
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• 제5권1호
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• pp.16-19
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• 2001

A photopolymer, copoly (M4Ch-ChMA), copoly ((4-methacryloyloxy) chalcone-cholesteryl methacrylate), was synthesized in this study. The electro-optical (EO) characteristics for the photo-aligned vertical-alignment (VA)-liquid crystal display (LCD) were investigated. Excellent voltage-transmittance curves for the VA-LCD photo-aligned by polarized UV exposure on the copoly (M4Ch-ChMA) surface were observed. The response time for the photo-aligned VA-LCD decrease with increasing UV exposure time. consequently, the photo-dimerized chalcone moiety increased with increasing UV exposure time, which then contributed to a low response time for the VA-LCD photo-aligned.

• 한국전기전자재료학회논문지
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• 제13권9호
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• pp.770-775
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• 2000

A new photo-polymer material of the copoly (PM4Ch-ChMA), copoly (poly (4-methacryloyloxy)chalcone-cholesteryl methacrylate) for homeotropic alignment was synthesized and the electro-optical (EO) performance for the photo-aligned vertical-aligned (VA)-LC display (LCD) was studied. Good thermal stabilities of synthesized copolymer were obtained by TGA(Thermogravimetric Analysis) measurement. Good voltage-transmittance (V-T) and response time characteristics for the photo-aligned VA-LCD with polarized UV exposure in oblique direction($\theta$$_{i}$=30$^{\circ}$) on a copolymer-1 (2%) surfaces for 1 min were observed. but, light leakage in the off-state was observed. Therefore, we achieved excellent V-T and response time characteristics for the photo-aligned VA-LCD with UV exposure on a copolymer-3 (30%) surfaces for 3 min.n.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 하계학술대회 논문집
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• pp.835-838
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• 2000

A new photo-alignment material, copoly (PM4Ch-ChMA), copoly (poly (4-methacryloyloxy) chalcone-cholesterol methacrylate) was synthesized and the electro-optical (EO) characteristics for the photo-aligned vertical-aligned (VA)-LC display (LCD) were studied. Good voltage-transmittance (V-T) and response time characteristics for the photo-aligned VA-LCD with polarized UV exposure on the copolymer-1 (2%) surfaces for 1 min. were observed. EO performance for the photo-aligned VA-LCD decreased with increasing UV exposure time on a copolymer surface. Also, excellent V-T and response time characteristics for the photo-aligned VA-LCD with UV exposure on copolymer-2 and copolymer-3 surfaces for 3min. can be achieved.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2000년도 추계학술대회논문집
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• pp.137-140
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• 2000

Synthesis of a new copoly (M4Ch-ChMA), copoly ((4-methacryloyloxy) chalcone-cholestery methacrylate), with chalconyl and cholesterol moiety characteristics for photoalignment materials was investigated. Good thermal stabilities of the synthesized copolymers are confirmed by thermogravimetric analysis (TGA) measurement. The pretilt angles of the nematic liquid crystal (NLC) are reduced as UV exposure time is increased on the copolymer surfaces. A pretilt angle of 81$^{\circ}$in NLC was observed with UV exposure of 3 min on the copolymer-3 surface. The NLCs pretilt angle is attributable to increased chalcone with increasing the UV exposure time.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2000년도 추계학술대회 논문집
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• pp.137-140
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• 2000

Synthesis of a new copoly (M4Ch-ChMA), copoly ((4-methacryloyloxy) chalcone-cholestery methacrylate), with chalconyl and cholesteryl moiety characteristics for photoalignment materials was investigated. Good thermal stabilities of the synthesized copolymers are confirmed by thermogravimetric analysis (TGA) measurement. The pretilt angles of the nematic liquid crystal (NLC) are reduced as UV exposure time is increased on the copolymer surfaces. A pretilt angle of 81$^{\circ}$ in NLC was observed with UV exposure of 3 min on the copolymer-3 surface. The NLCs pretilt angle is attributable to increased chalcone with increasing the UV exposure time.

• 한국광학회지
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• 제15권4호
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• pp.299-308
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• 2004

공액상 없이 여러 가지 물체를 동시에 재생 가능한 다채널 다단계 위상형 컴퓨터-생성 홀로그램(CGH)을 설계할 수 있는 보다 효과적인 부호화 방법을 제안하였다. 다채널 CGH 패턴을 설계하기 위하여 pixel oriented CGH 제작방식을 이용하였다. 설계된 CGH 패턴의 성능평가를 위해 양자화 위상 단계수에 따른 여러 가지 다채널 CGH들의 회절효율(η), 평균제곱에러(MSE) 및 신호 대 잡음비(SNR) 등의 변화를 살펴보았다. 일반적으로 CGH에 기록되는 물체 수가 증가할수록 CGH의 재생품질은 떨어진다. 그러나 회절효율의 경우 1채널 CGH가 70%이고 제안한 부호화 방법으로 설계한 2채널, 4채널, 8채널 CGH들은 각각 62%, 62%, 63%로 채널수가 증가하여도 큰 차이가 없음을 컴퓨터 모의실험을 통하여 확인할 수 있었다. 또한 렌즈로 결합되어 있는 PAL-SLM과 XGA형 LCD 그리고 이에 빛을 조명하는 LD 등으로 구성되어 있는 액정 공간 광 위상 변조기를 사용하여 광학적으로 CGH를 구현하여 입력영상을 재생$.$고찰해 보았다.