• 제목/요약/키워드: liquid-crystal display

검색결과 1,300건 처리시간 0.029초

Synthesis of Three Ring Type Compounds with Fluorine and NCS Groups as Candidates for VA mode Liquid Crystal Display

  • Heo, E.Y.;Kim, Y.B.;Kim, S.H.
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 한국정보디스플레이학회 2003년도 International Meeting on Information Display
    • /
    • pp.571-574
    • /
    • 2003
  • Three ring type liquid crystalline compounds having 4-alklycyclohexyl group, 1,2-difluorobenzene and phenylisothiocyanate moieties as main skeleton were designed to have negative dielectricity. However, the compounds with 2,3,2'-trifluoro-3'-isothiocyanated biphenylcyclohexane core did not exhibit the nematic liquid crystalline phase because of two conformers by interaction of isothiocyanate and adjacent fluorine atoms. Also, 4-alkyl-2,2',3'-trifluoro-3-isothiocyanated biphenylcyclohexane core was designed expecting to have uniform conformers of isothiocyanate group. In the course of developing polyimides for VA mode LCD, we synthesized alkyl-3,5-diaminobenzene efficiently with various length of alkyl chains from commercially available di-t-butyl malonate and 3,5-dinitrobenzoyl chloride as starting material.

  • PDF

Bending and Pressing Tolerance of Flexible Polyoxetane based Liquid Crystalline Polymer/Low Molecular Weight Liquid Crystal Device

  • Jang, Chi-Woong;Lim, Tong-Kun;Kim, Moo-Jong;Kim, Ku-Nam;Kwon, Young-Wan;Jin, Jung-Il;Bae, Jung-Hun;Kim, Han-Sik
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.I
    • /
    • pp.433-435
    • /
    • 2005
  • We have studied the realigning behavior of liquid crystal molecules in liquid crystalline polymer/liquid crystal(LCP/LC) system when they are exposed to external stimulation such as bending and pressing. The birefringence of the LCP/LC in a flexible display device was measured as a function of bending or pressing deformation. The microscopic dynamic behavior of main chain, side chain, and the LC were characterized by FTIR and polarization optical microscopy. When the device is deformed in scattering memory state, liquid crystal(LC) director is found to align from randomly oriented domain state(scattering state) to homeotropic state.

  • PDF

유전율 이방성이 음인 액정을 이용한 FFS 모드의 단일 갭형 반투과형 액정 디스플레이 연구 (Study on single gap transflective fringe-fields switching liquid crystal display using the liquid crystal with negative dielectric anisotropy)

  • 김진호;진미형;임영진;이승희
    • 한국전기전자재료학회:학술대회논문집
    • /
    • 한국전기전자재료학회 2008년도 추계학술대회 논문집 Vol.21
    • /
    • pp.312-313
    • /
    • 2008
  • A transflective liquid crystal displays associated with fringe field switching (FFS) mode of new concept is proposed. The device utilizes unique characteristic of the FFS mode in which the rotation angle of LC director is strongly dependent on electrode position in on state. We use the liquid crystal with negative dielectric anisotropy. Also we are look for optimized electrode size and the optimization of pixel electrode width and distance between them, the LC director could rotate about $22.5^{\circ}$ and $45^{\circ}$ depending on electrode positions. Consequently, we get high transmittance and high reflection on the optimized electrode condition. Respectively, a high image quality transflective display with single gap and single gamma characteristics realized.

  • PDF

Fabrication of a Flexible Cholesteric Liquid Crystal Display based on Pixel Isolation Method

  • Kwon, Ki-Sun;Kang, Dae-Seung
    • Journal of Information Display
    • /
    • 제6권1호
    • /
    • pp.8-11
    • /
    • 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.

In-plane Switching Liquid Crystal Cell with a Mixed Bent Electrode Structure for Fast Response Time

  • Ko, Tae-Woon;Kim, Jae-Chang;Lee, Joun-Ho;Choi, Hyun-Chul;Ji, Seung-Hoon;Choi, Jung-Min;Lee, Chul-Hun;Lee, Gi-Dong
    • Journal of Information Display
    • /
    • 제9권3호
    • /
    • pp.12-15
    • /
    • 2008
  • A bent electrode structure is proposed in the super in-plane switching (S-IPS) liquid crystal (LC), as it can reduce the response time without loss of transmittance in the bright state. The electrode angle in each position of the bent electrode was optimized to simultaneously achieve high transmittance and fast response time. The electro-optical characteristics of the proposed LC cell structure were experimentally compared with those of the conventional cell. It was observed that the response time became over 8% shorter without loss of transmittance when the proposed bent structure was applied.

An integrated elastomer substrate with a lens array and pixel elements for three-dimensional liquid crystal displays

  • Hong, Jong-Ho;Kim, Yeun-Tae;Kim, Yun-Hee;Lee, Byoung-Ho;Lee, Sin-Doo
    • Journal of Information Display
    • /
    • 제13권2호
    • /
    • pp.55-59
    • /
    • 2012
  • In this paper, a concept of an integrated elastomer substrate for a three-dimensional (3D) liquid crystal display based on the integral-imaging method is presented. The elemental lens array and columnar spacers were integrated into one of the two substrates, an elastomer substrate, through an imprinting process. The integrated elastomer substrate was capable of maintaining the uniform liquid crystal (LC) cell gap and promoting homeotropic LC alignment without any surface treatment. The monolithic approach reported herein will provide a key component for 3D displays with enhanced portability through a more than 40% weight reduction compared with the conventional integral-imaging method.

An RGB to RGBY Color Conversion Algorithm for Liquid Crystal Display Using RGW Pixel with Two-Field Sequential Driving Method

  • Hong, Sung-Jin;Kwon, Oh-Kyong
    • Journal of the Optical Society of Korea
    • /
    • 제18권6호
    • /
    • pp.777-782
    • /
    • 2014
  • This paper proposes an RGB to RGBY color conversion algorithm for liquid crystal display (LCD) using RGW pixel structure with two-field (yellow and blue) sequential driving method. The proposed algorithm preserves the hue and saturation of the original color by maintaining the RGB ratio, and it increases the luminance. The performance of the proposed RGBY conversion algorithm is verified using the MATLAB simulation with 24 images of Kodak lossless true color image suite. The simulation results of average color difference CIEDE2000 (${\delta}E^*_{00}$) and scaling factor are 0.99 and 1.89, respectively. These results indicate that the average brightness is increased 1.89 times compared to LCD using conventional RGB pixel structure, without increasing the power consumption and degrading the image quality.

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
    • /
    • 제7권1호
    • /
    • pp.7-11
    • /
    • 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.