• 제목/요약/키워드: Liquid crystal cell

검색결과 485건 처리시간 0.031초

Single-panel simulation on liquid crystal on silicon

  • Liao, Engle;Chiu, Jack;Peng, James
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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    • pp.939-942
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    • 2004
  • In this study, we report simulation results of single-panel LCOS (liquid crystal on silicon). Reflective LCOS microdisplays are widely used in various projection and near-eye application. For one panel system, liquid crystal response time is an important variable. The panel must switch fast enough to support the display of Field color sequential with high field rates. In order to have fast response and good contrast, a vertical alignment (VA) cell was used in this study. With suitable selection on LC parameters like temperature, viscosity, elastic constant and birefringence, it is possible to get response time of around 2ms from a 2.0 um-thick vertical alignment cell. This result also indicates an ease of production control on 2.0 um cells than 1.0 um cells.

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Light Leakage Comparison in a Homogeneously Aligned Nematic Liquid Crystal Display Depending on an Angle between Polarizer Axis and Optic Axis of a Liquid Crystal

  • Song, I.S.;Baik, I.S.;Won, H.K.;Kim, D.S.;Soh, H.S.;Kim, W.Y.;Lee, S.H.
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2004년도 Asia Display / IMID 04
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    • pp.1182-1184
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    • 2004
  • We have studied contrast ratio of a homogeneously aligned nematic liquid crystal (LC) display as a function of the angle between the polarizer axis and LC director. The results show that a cell configuration in which a polarizer axis facing a light source coincides with a short LC axis has a better process margin in terms of high contrast ratio than that of the cell coinciding with a long LC axis.

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폴리이미드막표면위에 경사진 자외선 조사를 이용한 네마틱 액정의 배향에 관한 연구 (A Study on Alignment of Nematic Liquid Crystal by Using Slanted Non-polarized Ultraviolet Light Irradiation on Polyimide Film)

  • 서대식;황율연;이보호
    • E2M - 전기 전자와 첨단 소재
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    • 제10권5호
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    • pp.461-466
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    • 1997
  • In this paper, we developed the new non-rubbing liquid crystal (LC) alignment techniques in the cell with slanted non-polarized ultraviolet (UV) light irradiation on polyimide (PI) film. It is shown that the uniform alignment for nematic (N) LC is obtained by using slanted non-polarized UV light irradiation on PI surface. We successfully obtained that the pretilt angle of NLC is generated about 3.3 degree in the cell with slanted non-polarized UV light irradiation with 70 degree on PI surface, for the first time. It is considered that the pretilt angle generation in NLC is attributed to interaction between the LC molecular and the PI, which is broken the polymer by slanted non-polarized UV irradiation. Therefore, we concluded that the uniform LC alignment is attributed to anisotropic dispersion force due to photo depolymerization with slanted non-polarized UV light irradiation on PI surface.

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Etchingless Fabrication of Bi-level Microstructures for Liquid Crystal Displays on Plastic Substrates

  • Hong, Jong-Ho;Cho, Seong-Min;Kim, Yeun-Tae;Lee, Sin-Doo
    • Journal of Information Display
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    • 제9권4호
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    • pp.6-10
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    • 2008
  • In this study, the selective-wettability-inscription (SWI) technique for the wet-etchingless fabrication of surface microstructures applicable to wide-viewing liquid crystal displays (LCDs) on plastic substrates was demonstrated. On the basis of the selective wetting of the photopolymer, the bi-level microstructures were spontaneously formed to serve as spacers for maintaining uniform cell gap and protrusions for the generation of multi-domains. The LC cell that has bi-level microstructures shows good extinction in the field-off state and a wide-viewing property in the field-on state. The SWI technique would be useful for the fabrication of flexible displays on plastic substrates.

Formation of High-Performance Polymer Walls in a Liquid Crystal Cell by Phase Separation of Fluorinated Polymer Mixture

  • Baek, Jong-In;Shin, Jong-Ba;Oh, Min-Cheol;Kim, Jae-Chang;Yoon, Tae-Boon
    • Journal of Information Display
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    • 제7권1호
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    • pp.7-11
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    • 2006
  • In this paper, we report the fabrication of high quality polymer walls by using a monomer containing fluorine (F-monomer). Polymer walls with no phase retardation were fabricated by using photo-polymerization induced anisotropic phase separation of the mixture composed of liquid crystal (LC) and F-monomer. Thanks to the immiscibility of fluoride, we could form high quality polymer walls with no light leakage. We measured electro-optic characteristics of a twisted-nematic (TN) LC cell whose polymer walls were fabricated by using the F-monomer, and the measurements were compared with that fabricated by using the monomer without fluorine.

Direct Formation of Bi-level Microstructures for Wide-viewing Liquid Crystal Displays with Plastic Substrates

  • Hong, Jong-Ho;Cho, Seong-Min;Kim, Yeun-Tae;Lee, Sin-Doo
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2008년도 International Meeting on Information Display
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    • pp.1286-1289
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    • 2008
  • We report on a wide-viewing liquid crystal (LC) display with bi-level microstructures spontaneously formed by selective wetting on a chemically heterogeneous surface. The bi-level microstructures serve as spacers for maintaining uniform cell gap, as well as protrusions for wide-viewing properties. Our LC cell having the bi-level microstructures shows good electro-optic properties.

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Three-Terminal Hybrid-aligned Nematic Liquid Crystal Cell for Fast Turn-off Switching

  • Baek, Jong-In;Kim, Ki-Han;Kim, Jae-Chang;Yoon, Tae-Hoon
    • Journal of Information Display
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    • 제10권1호
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    • pp.16-18
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    • 2009
  • A three-terminal hybrid-aligned nematic liquid crystal (3T-HAN LC) cell capable of fast turn-off switching is proposed in this paper. By employing the relaxation process initiated by an electric-field pulse, a fast turn-off time of less than 1 ms can be obtained through optically hidden relaxation. A low operating voltage and high transmittance were confirmed through simulations and experiments.

경사 전기장 구동에 의한 수평배열 액정 디스플레이의 전기 광학특성 연구 (Electro-optic Characteristic of Homogeneously Aligned Liquid Crystal Display Driven by an Oblique field)

  • 박상현;이지연;이승희
    • 한국전기전자재료학회논문지
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    • 제19권1호
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    • pp.81-86
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    • 2006
  • We have studied electrode-optic characteristics of in-plane switching (IPS) of liquid crystal director driven by an oblique electric field. Because the conventional IPS mode does not have an electrode on top substrate, it shows not only slow response time due to weak electric field but also slow discharging problem when electrostatic field is generated after fabricating the cell. To solve these problems, we have formed additional electrode including dielectric layer in the inner part of the cell on top substrate and studied electrode-optic characteristics of the new device.

프로젝션 TV 적용을 위한 액정 디스플레이의 열적 및 UV 안전성에 관한 연구 (Study on thermal and UV stability of Liquid Crystal Display for Projection TV Application)

  • 최성호;황정연;배유한;이휘원;서대식
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2005년도 추계학술대회 논문집 Vol.18
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    • pp.287-288
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    • 2005
  • In this study, we have investigated electro-optical characteristics of thermal and UV stressed TN cells on the rubbed polyimide surface. Mono-domain alignments of thermal stressed TN cells over temperature of liquid crystal isotropic phase were almost same that of no thermal stressed TN cells. Also, threshold voltage and response time of thermal stressed TN cells were same that of no thermal stressed TN cells. Finally, the residual DC voltage of the thermal stressed TN cell on the polyimide surface show decrease of characteristics as increasing thermal stress time. Therefore, thermal stability of TN cell was decreased by high thermal stress for the long times.

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Light efficiency of fringe-field switching nematic liquid crystal cell depending on dielectric anisotropy value of a liquid crystal

  • Ryu, Je-Woo;Lee, Ji-Youn;Park, Ji-Woong;Lee, Seung-Hee;Lee, Gi-Dong
    • 한국정보디스플레이학회:학술대회논문집
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    • 한국정보디스플레이학회 2007년도 7th International Meeting on Information Display 제7권1호
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    • pp.560-563
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    • 2007
  • The light efficiency of fringe-field switching (FFS) mode was found to be dependent on the magnitude of dielectric anisotropy, indicating that the voltagedependent maximal effective cell retardation value in the on state is a function of magnitude of the dielectric anisotropy of the LC.

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