• 제목/요약/키워드: Liquid crystal polymer

검색결과 449건 처리시간 0.03초

키랄네마틱액정-고분자 복합막의 경화거동과 내부구조에 관한 연구 (A Study on Curing Behaviors and Structures of Chiral Liquid Crystal-Polymer composite films)

  • 남수용;김종원;김용욱
    • 한국인쇄학회지
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    • 제16권3호
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    • pp.15-27
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    • 1998
  • Several aspects of polymer dispersed liquid crystal(PDLC) film properties make them interesting for display application. Most versions of PDLC materials are able to modulate light without the use of polarizers, which offers advantages in optical throughput(brightness) and viewing angle compared to polarizer-based display. In this papers, we attemped to doe minimum of remaining liquid crystals at polymer network for the liquid crystal-polymer composite (LCPC) films. In results, best phase separation behaviors turned out liquid crystal/monomer/oligomer mixture system.

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Fabrication and electro optical properties of stressed liquid crystal cell

  • Lee, Jung-Min;Park, Jin-Seol;Kang, Dae-Seung
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2009년도 9th International Meeting on Information Display
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    • pp.681-682
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    • 2009
  • We fabricated a stressed liquid crystal cell by mixing liquid crystal with a photo-polymer. By carefully choosing the mixing ratio between liquid crystal and the polymer, and by suitable mechanical shearing of the substrates, we demonstrated feasible electro optical properties for displays.

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Temperature Dependence of the Electro-optic Characteristics in the Liquid Crystal Display Switching Modes

  • Jeon, Eun-Jeong;Srivastava, Anoop Kumar;Kim, Mi-Young;Jeong, Kwang-Un;Choi, Jeong-Min;Lee, Gi-Dong;Lee, Seung-Hee
    • Journal of Information Display
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    • 제10권4호
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    • pp.175-179
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    • 2009
  • As the physical properties of nematic liquid crystals vary with respect to temperature, the performances of liquid crystal displays (LCDs) are highly dependent on temperature. Additionally, it is well known that the electro-optic characteristics of LCDs, such as transmittance and threshold voltage, also rely on the LCD switching modes. The temperature dependence of the electro-optic characteristics of the wide-viewing-angle LCD modes, such as in-plane switching (IPS), multidomain vertical alignment by patterned electrode (PVA), and fringe-field switching (FFS), have been studied, and the results showed that the FFS mode has lower temperature dependence compared to the IPS and PVA modes. Since the liquid crystal (LC) reorients in different ways in each mode, this result is associated with the temperature dependence of LC's bend and twist elastic constants, and also with the position of the main reorientation, either in the middle or on the surface of the LC layer.

Single-Layer Color Cholesteric Liquid Crystal Displays

  • Lu, Shin-Ying;Lin, Yu-hui;Chien, Liang-Chy
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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    • pp.982-985
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    • 2007
  • The authors report methods of fabrication singlelayer color cholesteric liquid crystal displays (CLCDs). A single-layer CLCD has been prepared from a polymerstabilized cholesteric liquid crystal. The unique feature of the polymer stabilization is in that the electrically switched colors preserve high reflectivity. A bistable single-layer CLCD has been prepared by the formation of polymer barrier walls and light-tuned cholesteric pitches to reflect blue, green and red color sub-pixels.

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Stability-Enhanced Liquid Crystal Mode for Flexible Display Applications

  • Jung, Jong-Wook;Jang, Se-Jin;Lee, You-Jin;Kim, Hak-Rin;Jin, Min-Young;Kim, Jae-Hoon
    • Journal of Information Display
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    • 제6권2호
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    • pp.1-6
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    • 2005
  • We demonstrated stability-enhanced liquid crystal (LC) displays using pixel-isolated LC mode in which LC molecules are isolated in pixel by horizontal polymer layer and vertical polymer wall. The device shows good electro-optic properties against external point or bending pressure due to the polymer structures. The polymer wall acts as supporting structure from mechanical pressure and prevents the cell gap from bending. Moreover, the polymer layer acts as an adhesive to ensure a tight attachment of the two substrates. We present herein various methods for producing polymer structures by using an anisotropic phase separation from LC and polymer composites or patterned micro-structures for stable flexible liquid crystal displays.

폴리머 분산 액정의 전기 광학적 스위칭 특성에 대한 액정방울 크기의 효과 (Effect of droplet size on electro-optical switching properties of polymer dispersed liquid crystals)

  • 김인태;유연석
    • 한국광학회지
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    • 제17권1호
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    • pp.23-30
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    • 2006
  • 폴리머 분산 액정의 전기광학 스위칭 특성에 대한 액정 방울 크기의 효과를 실험적으로 연구하였다. 액정 방울의 크기는 상 분리를 위해 조사하는 레이저 광원의 세기와 LC/oligomer의 혼합 비율에 따라 변화되었다. 전기 광학적 스위칭 전압은 LC/oligomer의 혼합비율과 액정의 방울 크기에 크게 의존하였다. 실험 결과를 보면 상 분리용 조사 레이저광의 세기가 클 때 액정방울의 크기는 작아졌고 포화투과도 전압은 상승했지만 rise time은 짧아 졌다.

액정의 Kerr 효과를 이용한 액정표시소자 연구 (Study on Liquid Crystal Displays Utilizing Kerr effect)

  • 김민수;강병균;정준호;하경수;송은경;윤석인;김미영;이명훈;이승희
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2009년도 하계학술대회 논문집
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    • pp.295-296
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    • 2009
  • There are various application of liquid crystal materials to devices, especially, blue phase liquid crystal (BPLC) and nano-structured liquid crystal mixture have been studied recently because BPs existing temperature range has been expanded by polymer-stabilization and liquid crystal has been confined in room which has certain coherence length so that their particular characters, such as fast response time and optically isotropic state at no electric field, could apply to advanced liquid crystal display devices. However, there is an crucial problem which is high operating voltage from low Kerr constant and limited electric field utilization using in-plain electric field. In this paper, we will analyze cell structure in the way of using electric field and show effective electric field utilization to reduce operating voltage.

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고분자 층이 도입된 네마틱 액정 시스템의 광굴절 효과 기작 (Mechanism of Photorefractive Effect in Polymer Layered Nematic Liquid Crystal Systems)

  • Mun Jun-Ho;Yun Chun-Seop;Kim Hyeon-Uk;Choe Su-An;Kim Jong-Deuk
    • 한국광학회:학술대회논문집
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    • 한국광학회 2001년도 제12회 정기총회 및 01년도 동계학술발표회
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    • pp.206-207
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    • 2001
  • The photorefractive (PR) effect in liquid crystals sandwiched between photoconductive polymer layers was first studied by Ono et al. They reported that the PR effect vanished at steady state If there were not insulating layers because no charge trapping occurred in the photoconductive poly(N-vinylcarbazole) (PVK) layers. However we observed a significant PR effect in the polymer layered liquid crystal (PLLC) system where a liquid crystal layer doped with fullerene is sandwiched between two photoconductive PVK layers. (omitted)

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