• Title/Summary/Keyword: Liquid crystal

Search Result 2,543, Processing Time 0.029 seconds

Effect of the Molecular Structure of Rubbed Polyimide Films for Surface Liquid Crystal Alignment of Nematic Liquid Crystal (네마틱 백정의 표면 액정 배향에관한 폴리이미드막의 분자 구조의 효과)

  • 서대식
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 1996.05a
    • /
    • pp.232-234
    • /
    • 1996
  • We have investigated the effect of molecular structure of polymer of rubbed polyimide (PI) films for surface liquid crystal alignment. To obtain surface alignment effect of Polymer molecular structure, we measured the polar (out of plane-tilt) anchoring strength and surface ordering of 5CB on rubbed PI surfaces. We have found that the polar anchoring strength of 5CB is depend on the polymer molecular structure of these unidirectionally rubbed PI surfaces.

  • PDF

Liquid Crystal Alignment on Patterned Micro-grooved Polyimide Surfaces

  • Chiou, D.R.;Chen, L.J.;Lee, C.D.;Liu, H.M.
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2005.07a
    • /
    • pp.774-777
    • /
    • 2005
  • In this work, a soft embossing method is proposed to fabricate microgrooves on polyimide surfaces. Apply these resulting patterned micro-grooved polyimide surfaces as the liquid crystal alignment layers. The director of liquid crystal molecules aligns perfectly along the direction of microgrooves.

  • PDF

Azo-Dyes Photo-Aligning; Physics and Applications

  • Chigrinov, V.G.;Kwok, H.S.;Takada, Hirokazu;Takatsu, Haruyoshi
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2005.07a
    • /
    • pp.759-763
    • /
    • 2005
  • This review presents the status of our research in liquid crystal display (LCD) photo-aligning. We present the basic mechanisms of the photo-induced order in various photo-aligning materials and in azo-dye layers in particular and show that photo-aligning methods can provide a controllable pretilt angle and anchoring energy of the liquid crystal cell, as well as its high thermo and UV stability. The photo-aligning of various types of liquid crystal displays is also discussed.

  • PDF

A model of adsorption of liquid crystal on the polymer surface based on the analysis of the surface alignment of the adsorbed layer

  • Oh, Se-Jun;Miyashita, Tetsuya;Uchida, Tatsuo
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2009.10a
    • /
    • pp.940-941
    • /
    • 2009
  • The adsorption strength of liquid crystal molecules on the polymer surface was compared measuring temperature dependence of retardation above Nematic-Isotoropic transition temperature ($T_{NI}$). The relationship between surface order parameter and adsorption strength on the polymer surface was discussed.

  • PDF

Transflective Liquid Crystal Display with High Aperture Ratio using Electrophoresis Particles

  • Cheong, Seung-Hwan;Bae, Kwang-Soo;Yu, Chang-Jae;Kim, Jae-Hoon
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2009.10a
    • /
    • pp.166-168
    • /
    • 2009
  • We proposed a transflective liquid crystal display (LCD) with high aperture ratio using an electrophoretic particle layer (EPL). The transflective LCD consisted of the stacked LC layer and EPL which was acted as a switchable mirror under in-plane electrode structure. Without separation of reflective part and transmissive part in one pixel, a modeselectable display device can be obtained.

  • PDF

Voltage Holding Ratio of a Homogeneously-Aligned Liquid-Crystal Cell

  • Lin, Yu-Ting;Lin, Yu-Jiun;Lee, Wei
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2009.10a
    • /
    • pp.17-19
    • /
    • 2009
  • The voltage and frequency dependence of voltage holding ratio (VHR) in a homogeneously-aligned liquid-crystal (LC) cell is studied in this paper. The discharge curves with different scan frequencies are obtained and the saturation phenomenon of VHR is observed under specific amplitudes of driving voltage. Our results suggest a reasonable concept to improve the VHR in LC displays without increasing the frame rate.

  • PDF

Twisted Nematic LC Modulator for TFT Array Inspection

  • Bae, B.S.;Park, D.H.;Lee, H.K.;Lee, S.E.;Kim, S.H.;Jeong, D.H.;Rho, B.G.
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2007.08a
    • /
    • pp.290-292
    • /
    • 2007
  • A twisted nematic type liquid crystal electro-optic modulator (TN-LC modulator) was developed. The modulator used single polarizer and the reflection on-off ratio was maximized by optimization of twist angle and retardation of liquid crystal cell. The TNLC modulator shows better sensitivity and response time than conventional liquid crystal modulator.

  • PDF

Experimental and Numerical Study on Anisotropic Phase Separation of Liquid Crystal and Polymer Composites Cell Gap Variation

  • Jin, Min-Young;Bae, Ji-Hong;Kim, Jae-Hoon
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2007.08a
    • /
    • pp.567-570
    • /
    • 2007
  • Cell gap dependence on anisotropic phase separation was studied. The results showed that the morphology of phase separation depended on cell gap and material parameters. With numerical simulation and experiments, the optimal range of cell gap in the formation of polymer layer and liquid crystal was suggested for given material parameters.

  • PDF

Adjustable Pretilt Angle of Liquid Crystal Alignment Materials

  • Lin, Song-Shiang;Lee, Chein-Dhau;Su, Ya-Ting;Lee, Yu-Der
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2007.08a
    • /
    • pp.80-82
    • /
    • 2007
  • We have developed a series of fluorinated dimethacrylate copolymers. Our work has covered the synthesized derivatives of alignment materials, characterized the pretilt angle and uniformity of liquid crystal alignment layer. The pretilt angle can be tailored by using the fluorinated copolymer. Excellent uniformity was achieved as shown in experimental results.

  • PDF

Review of Liquid Crystal Spatial Light Modulators at Thales Research & Technology;Technology and Applications

  • Lee, Mane-Si Laure;Loiseaux, Brigitte;Dolfi, Daniel;Tonda, Sylvie;Huignard, Jean-Pierre
    • Journal of Information Display
    • /
    • v.3 no.3
    • /
    • pp.24-29
    • /
    • 2002
  • Liquid Crystal Spatial Light Modulators (LC-SLMs) provide many interesting applications in laser optics and opto-el ectronic systems, in addition to displays. Among them, three topics developed at Thales Research & Technology are reviewed: wavefront correction for laser beam control, microwave processing in radar systems and holography for TN-LCDs viewing angle compensation.