• Title/Summary/Keyword: Reflective liquid crystal display

Search Result 99, Processing Time 0.028 seconds

Design and testing large FOV retinal displays on the basis holographic combiner

  • Gan, Mikhail A.;Gan, Iacov M.;Tchertkov, Alexander S.
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2004.08a
    • /
    • pp.442-445
    • /
    • 2004
  • We report principles and results of design large FOV retinal display systems by software WinDEMOS and software for computer testing display systems TEDiS. We discuss results design head mounted and head up display. As combiner we are used volume interference recorded or synthetic HOE, and as the sours of the image high resolution transmitting or reflective liquid crystal matrixes on silicon (LCOS) or CRT.

  • PDF

A Transflective Liquid Crystal Display Driven by the Fringe Field Using a Liquid Crystal with a Negative Dielectric Anisotropy

  • Kim, Jin-Ho;Her, Jung-Hwa;Lim, Young-Jin;Kumar, Pankaj;Lee, Seung-Hee;Park, Kyoung-Ho;Lee, Joun-Ho;Kim, Byeong-Koo
    • Transactions on Electrical and Electronic Materials
    • /
    • v.11 no.3
    • /
    • pp.134-137
    • /
    • 2010
  • We have proposed a transflective liquid crystal display (LCD) driven by the fringe field using a liquid crystal (LC) with a negative dielectric anisotropy. The device used different twist angles of the liquid crystals (LC) in the transmissive (T) and the reflective (R) regions when voltage is applied. With the optimization of the pixel electrode width and the distance between them, the LC directors in the R- and T-regions can be rotated by about $22.5^{\circ}$ and $45^{\circ}$ on an average, respectively. As a result, a high image quality transflective LCD with a single gap, a single gamma, and a wide viewing angle characteristics in both the R- and T- regions can be realized.

Transflective IPS LCD with Multi-Domain Structures

  • Park, Kyoung-Ho;Ko, Young-Jo;Kim, Jung-Hyoung;Kim, Jae-Chang;Yoon, Tae-Hoon
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2004.08a
    • /
    • pp.895-898
    • /
    • 2004
  • We propose configurations for a transflective in-plane switching (IPS) cell using muti-domain structures. Usually, the cell configurations for a transflective liquid crystal(LC) cell have a complicated structure, because retardation change of transmissive part and reflective part are not same. The transflective LC cell should have two configurations for each part, such as a multi-cell gap structure. With the ion-beam alignment and the horizontal switching LC cell, a simple structure for a transflective LC cell is proposed. The configuration only adopts one cell gap structure, which may help the enhancement of a yield. Their original optical properties in conventional transmissive and reflective type IPS liquid crystal dispaly(LCD) are kept, it shows the wide-viewing angle and the good wavelength dispersion characteristics.

  • PDF

Power Consumption and Viewing Angle Characteristics Dependent on Liquid Crystal's Twist Angle in Reflective Twisted Nematic Mode (반사형 TN mode의 Twist angle에 따른 소비전력과 시야각 특성)

  • 송제훈;정태봉;이승희
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
    • /
    • v.17 no.2
    • /
    • pp.207-211
    • /
    • 2004
  • We have performed computer simulation to obtain a globa1 optimization of power consumption and viewing angle characteristic of reflective twisted nematic (R-TN) mode liquid crystal display (LCD) with sin81e polarizer and λ/4 plate. Our studies shout that with increasing the twist angle, a steepness of reflectance-voltage curve increase, operation voltages decreases, the region where contrast ratio (CR) greater than 10 increases but the reflectance of the white state starts to decrease at above the twist angle of 75$^{\circ}$. Above the twist angle of 90$^{\circ}$, the R-TN mode LCD shows the most favorable combination of low consumption and good viewing angle characteristic.

Energy Reduction in LCD Displays

  • Liu, Tao;O'Neill, Mark;Hoffman, Kevin M.;Sanford, Quinn D.;Serres, Alan M.;Schiller, Robert
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2008.10a
    • /
    • pp.780-783
    • /
    • 2008
  • Low-loss optical films can be used in LCD backlights to improve the display efficiency. Improvements can be used to enhance display performance, increase functionality and reduce energy costs.

  • PDF

RGBW Transflective TFT LCDs with Adjustable Reflective Color Gamut by Image Processing Algorithm

  • Yang, Tun-Chun;Hung, Kuo-Yung;Pei, Chih-Chun;Hu, Chih-Jen;Chang, Chih-Ming;Chen, Po-Lun;Lin, Kun-Yu
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2006.08a
    • /
    • pp.209-214
    • /
    • 2006
  • Adjustable reflective color gamut RGBW transflective liquid crystal display (ARC RGBW TRLCD) applied simple manufacture process and image processing algorithm to achieve high brightness and good color performance both in transmissive and reflective mode. With appropriate modification higher transmittance but no color distortion happens in transmissive mode. Moreover, base on superior reflectance total brightness and color gamut also can be modified under different ambience. It provides the flexibility not only for any environments but also for variant personal hobbies. It is the best technique used both at indoor and outdoor.

  • PDF

Optimal pixel design for low driving single gamma curve and single gap transflective fringe field switching display (단일랩 반투과 FFS 액정 디스플레이를 위한 최적 화소 디자인)

  • Jeong, Youn-Hak;Lim, Young-Jin;Jeong, En;Lee, Jeung-Hee
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2007.06a
    • /
    • pp.435-436
    • /
    • 2007
  • In general, Single gap transflective FFS display has an in-cell retarder (ICR) between reflective electrode and liquid crystal (LC) layer. Therefore, Operating voltage is highly increased due to this thick dielectric material. But, we also knew the phenomenon that the increasing rate of Vop is different whether the 1st common electrode was composed of plate type or slit type. In this paper, the common electrode in transmissive part was composed of slit type which had less steepness effect of the V op and in reflective part was composed of plate type. The rubbing angle of reflective part can be adjusted properly to match the voltage dependent transmittance and reflectance.

  • PDF

Electro-optical Characteristics of Transflective Liquid Crystal Display using the PVA mode (PVA 모드를 이용한 반투과형 액정디스플레이의 전기광학 특성)

  • Jeon, Yeon-Mun;Lim, Young-Jin;Kim, Youn-Sik;Kim, Sang-Gyun;Lyu, Jae-Jin;Lee, Seung-Hee
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
    • /
    • 2006.06a
    • /
    • pp.461-462
    • /
    • 2006
  • A single-gap and single-gamma transflective liquid-crystal (LC) display using patterned vertical alignment (PVA) mode was designed. In the device, a vertical electric field drives a vertically aligned LC to tilt down to optimize polarization efficiency. Electrodes of transmissive and reflective area were patterned $22.5^{\circ}$ and $45^{\circ}$ with respect to the polarizer so that a tilt-down direction of the LC director was $22.5^{\circ}$ and $45^{\circ}$ in the reflective and transmissive regions, respectively. In the device, the cell gap was the same for both regions, and the gamma curve matched each other in both regions because tilt angle of LC director was the same according to the applied voltage. Moreover, the dark state was irrespective of the cell retardation value at normal direction, which was highly important in massive fabrications. The switching principle and electro-optic characteristics of the device are reported herein.

  • PDF

Correlation Between the Optical Performance of the Reflective Polarizer and the Structure of LCD Backlight

  • Yu, Mi-Yeon;Lee, Byung-Woo;Lee, Jeong-Ho;Ko, Jae-Hyeon
    • Journal of the Optical Society of Korea
    • /
    • v.13 no.2
    • /
    • pp.256-260
    • /
    • 2009
  • The optical performance of the reflective polarizer was investigated over three kinds of direct-lit backlights and/or different configurations of the optical sheets. The optical gain factor achieved by using the reflective polarizer increased as the diffuse nature of the optical sheet was enhanced, because of the more efficient polarization conversion. In addition, the gain factor decreased substantially in flat-lamp backlights compared to tubular-lamp backlights, which was ascribed to the high loss factor during the polarization recycling process due to the complex structure and large area of flat lamps. All these results suggested that reducing the loss factor of the backlight is very important for efficient polarization conversion and thus high optical gain of the reflective polarizer.

Photoalignment of Liquid Crystal on Silicon Microdisplay

  • Zhang, Baolong;Li, K. K.;Huang, H. C.;Chigrinov, V.;Kwok, H. S.
    • 한국정보디스플레이학회:학술대회논문집
    • /
    • 2003.07a
    • /
    • pp.295-298
    • /
    • 2003
  • Reflective mode liquid crystal on silicon (LCoS) microdisplay is the major technology that can produce extremely high-resolution displays. A very large number of pixels can be packed onto the CMOS circuit with integrated drivers that can be projected to any size screen. Large size direct-view thin film transistor (TFT) LCDs becomes very difficult to make and to drive as the information content increases. However, the existing LC alignment technology for the LCoS cell fabrication is still the mechanical rubbing method, which is prone to have minor defects that are not visible normally but can be detrimental if projected to a large screen. In this paper, application of photo-alignment to LCoS fabrication is presented. The alignment is done by three-step exposure process. A MTN $90^{\circ}$ mode is chose as to evaluate the performance of this technique. The comparison with rubbing mode shows the performance of photo-alignment is comparable and even better in some aspect, such as sharper RVC curve and higher contrast ratio.

  • PDF