• 제목/요약/키워드: Nematic liquid crystal(NLC)

검색결과 177건 처리시간 0.021초

소성온도에 따른 광유기된 프리틸트와 액정배향 (Liquid crystal alignment and photo-induced pretilt by imidization temperature.)

  • 서대식;김형규
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 1999년도 추계학술대회 논문집
    • /
    • pp.533-536
    • /
    • 1999
  • In this study, we investigated pretilt angle generation and liquid crystal alignment by UV light irradiation during imidization of polyimide. Generated pretilt angle of NLC by using in-situ UV photo-alignment method was smaller than that of the conventional UV photo-alignment method. Also, generated pretilt angle of NLC tends to increase by annealing. We found that in-situ UV photo-alignment method has higher thermal stability of LC alignment, but it has a disadvantage to control pretilt angle.

  • PDF

전사배향법을 이용한 네마틱액정의 프리틸트각 발생에 관한 연구 (Investigation of Pretilt Angle Generation in thematic Liquid Crystal by Using Transcription alignment)

  • 서대식;김진호;한정민;이정호
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 1997년도 춘계학술대회 논문집
    • /
    • pp.123-126
    • /
    • 1997
  • In this study, we investigated the Pretilt ang1e generation in nematic liquid crystal (NLC) by using the transcription, alignment on polyimide(Pl) surfaces. That the uniform alignment of NLC is observed by microphotograph textures in LC cells on Pl surface. We obtained that the pretilt angle of NLC are generated about 3.6$^{\circ}$on Pl surface. It is considered that the LC alignment by transcription alignment method is attributed to memory effect of LC on Pl surface.

  • PDF

러빙처리된 플렉시블 액정표시소자의 전기광학특성 (Electro-optical Characteristics on the Rubbing-aligned Flexible Liquid Crystal Display)

  • 남기형;황정연;김종환;서대식
    • 한국전기전자재료학회논문지
    • /
    • 제17권8호
    • /
    • pp.866-870
    • /
    • 2004
  • We have investigated the generation of pretilt angle for a nematic liquid crystal (NLC) alignment with rubbing alignment method on polyimide surfaces using plastic substrates. It was found that monodomain alignment of NLC is obtained with rubbing alignment method on polyimide surfaces using thin plastic substrates. The NLC pretilt angles on thin plastic substrates generated higher than that on glass substrate. Also, EO characteristics of the TN-LCD with a rubbed PI surface based on polymer substrate are almost the same as that of the TN-LCD with a rubbed PI surface based on glass. However, the transmittances of the TN-LCD with a rubbed PI surface based on polymer is less than that with a rubbed PI surface based on g1ass.

전사배향법을 이용한 씰의 액정배향의 효과 (Effect of Liquid Crystal alignment in the cell using transcription alignment method)

  • 서대식;김진호;최재학
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 1998년도 춘계학술대회 논문집
    • /
    • pp.271-274
    • /
    • 1998
  • In this paper, the monodomain alignment of nematic liquid crystal(NLC) in the cell fabricated by one side transcription alignment method on PI surface with side chain were investigated. The LC alignment produced by the transcription alignment method is attributable to a memory effect of the NLC on Pl surfaces. We observed that the pretilt angle of NLC is generated about 3.6$^{\circ}$ in a cell with one side transcription alignment on PI surface. Also, the electro-optical(EO) performance of TN-LCD with one side transcription alignment method on PI surface will be discussed.

  • PDF

러빙천의 종류에 의한 네마틱 액정의 배향 및 프리틸트각의 발생 (Effect of the Rubbing Fabric for Liquid Crystal Alignment and Pretilt Angle Generation)

  • 서대식
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1997년도 하계학술대회 논문집 C
    • /
    • pp.1577-1578
    • /
    • 1997
  • We have studied the effect of the rubbing fabric for liquid crystal alignment and pretilt angle generation in nematic liquid crystals (NLC), 4-cyano-4-n-penthylbiphenyl (5CB), on rubbed polyimide (PI) surfaces. The pretilt angle of 5CB for nylon and rayon fabric is larger than that of cotton fabric in weak rubbing on rubbed PI surfaces. We conclude that the pretilt angle of 5CB is strongly related to the rubbing fabrics on rubbed PI surfaces.

  • PDF

Homeotropic Alignment Effect for Nematic Liquid Crystal on the SiOx Thin Film Layer by New Ion Beam Exposure

  • Han, Jeong-Min;Choi, Sung-Ho;Kim, Byoung-Yong;Han, Jin-Woo;Hwang, Jeoung-Yeon;Ok, Chul-Ho;Seo, Dae-Shik
    • Transactions on Electrical and Electronic Materials
    • /
    • 제7권6호
    • /
    • pp.293-296
    • /
    • 2006
  • We studied homeotropic alignment effect for a nematic liquid crystal (NLC) on the $SiO_{x}$ thin film irradiated by the new ion beam method. $SiO_{x}$ thin films were deposited by plasma enhanced chemical vapor deposition (PECVD) and were treated by the DuoPIGatron ion source. A uniform liquid crystal alignment effect was achieved over 2100 eV ion beam energy. Tilt angle were about $90^{\circ}$ and were not affected by various ion beam energy.

측쇄기를 가진 폴리머의 폴리이미드 소성 방법에 따른 액정 배향 효과 (Liquid crystal alignment effects by imidization methods of the polyimide on the polymer with side chain.)

  • 서대식;김형규
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2000년도 춘계학술대회 논문집 디스플레이 광소자 분야
    • /
    • pp.177-180
    • /
    • 2000
  • In this study, we investigated the pretilt angle generation and liquid crystal (LC) alignment by ultraviolet (UV) exposure during imidization of polyimide on the polymer with side chain. The generated pretilt angle of nematic (N) LC using in-situ photo-alignment method was smaller than that of the conventional UV photo-alignment method. Also, the generated pretilt angle of NLC tends to increase by annealing.

  • PDF

고분자 막을 이용한 이온빔 배향 TN-LCD의 전기광학특성 (Electro-optical characteristics of TN-LCD on a Polyimide Surface Exposed to an Ion Beam)

  • 김상훈;황정연;강형구;배유한;이휘원;서대식
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
    • /
    • pp.271-272
    • /
    • 2005
  • We studied liquid crystal (LC) alignment with ion beam (IB) on polyimide and electro-optical characteristics of twisted nematic (TN)-liquid crystal display (LCD) on the polyimide surface using obliquely ion beam exposure. A good uniform alignment of the nematic liquid crystal (NLC) alignment with the ion beam exposure on the polyimide surface was observed. In addition, it can be achieved the good EO properties, and residual DC property of the ion-beam-aligned TN-LCD on polyimide surface.

  • PDF

Alignment Effect of a Nematic Liquid Crystal on Deposited SiOx Thin-Film Surface with e-beam Evaporation

  • Oh, Yong-Cheul;Lee, Dong-Gyu
    • Transactions on Electrical and Electronic Materials
    • /
    • 제7권6호
    • /
    • pp.305-308
    • /
    • 2006
  • We have studied liquid crystal (LC) aligning capabilities for homeotropic alignment and the control of tilt angles on the $SiO_{x}$ thin film by electron beam evaporation method. A high tilt angle of about $86.5^{\circ}$ was obtained, and also the suitable tilt angle of the NLC on the $SiO_{x}$ thin film at $20{\sim}50\;nm$ thickness with e-beam evaporation can be achieved. The uniform LC alignment on the $SiO_{x}$ thin film surfaces with electron beam evaporation can be achieved. It is considerated that the LC alignment on the $SiO_{x}$ thin film by electron beam evaporation is attributed to elastic interaction between LC molecules and micro-grooves at the $SiO_{x}$ thin film surface created by evaporation.

NDLC 박막을 이용한 네마틱 액정의 고프리틸트 제어 (Control of High Pretilt Angle in NLC using a NDLC Thin Film)

  • 박창준;황정연;서대식;안한진;김경찬;백홍구
    • 한국전기전자재료학회논문지
    • /
    • 제17권7호
    • /
    • pp.760-763
    • /
    • 2004
  • We studied the nematic liquid crystaL(NLC) aligning capabilities using the new alignment material of a nitrogenated diamond-like carbon(NDLC) thin film. The NDLC thin film exhibits high electrical resistivity and thermal conductivity that are similar to the properties shown by diamond-like carbon (DLC) thin films. The diamond-like properties and nondiamond-like bonding make NDLC an attractive candidate for applications. A high pretilt angle of about 9.9$^{\circ}$ by ion beam(IB) exposure on the NDLC thin film surface was measured. A good LC alignment is achieved by the IB alignment method on the NDLC thin films surface at annealing temperature of 200 $^{\circ}C$. The alignment defect of the NLC was observed above annealing temperature of 250 $^{\circ}C$. Consequently, the high pretilt angle and the good LC alignment by the IB alignment method on the NDLC thin film surface can be achieved.