Light-reflecting characteristics of optically rewritable electronic paper

Abstract Light-reflecting characteristics play a crucial role in optically rewritable liquid crystal display (electronic paper). By using a special optimizer software, light-reflecting characteristics of the twisted nematic cell were calculated. The achieved values of the normalized reflection coefficients range within ∼ 0.03 - 0.43, which is comparable or better than other commercial technologies. The calculated contrast ratio of the device is 10 : 1. A 2D image, which can be displayed on the electronic paper was obtained. Comparison of the simulated background color and contrast ratio is very similar with the results, which were obtained in experimental cells of other studies. Our calculations indicate that angular dependence of the reflectance coefficient is almost uniform within a wide range of viewing angles.

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Enhancement of Contrast Ratio by Using Ferroelectric Nanoparticles in the Alignment Layer of Liquid Crystal Display

Japanese Journal of Applied Physics ◽

10.1143/jjap.47.4751 ◽

2008 ◽

Vol 47 (6) ◽

pp. 4751-4754 ◽

Cited By ~ 18

Author(s):

Sudarshan Kundu ◽

Mitsuhiro Akimoto ◽

Itaru Hirayama ◽

Masaru Inoue ◽

Shunsuke Kobayashi ◽

...

Keyword(s):

Liquid Crystal ◽

Liquid Crystal Display ◽

Contrast Ratio ◽

Alignment Layer

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Phase-only modulation with a twisted nematic liquid crystal display by means of equi-azimuth polarization states

Optics Express ◽

10.1364/oe.14.005607 ◽

2006 ◽

Vol 14 (12) ◽

pp. 5607 ◽

Cited By ~ 23

Author(s):

V. Durán ◽

J. Lancis ◽

E. Tajahuerce ◽

M. Fernández-Alonso

Keyword(s):

Liquid Crystal ◽

Nematic Liquid Crystal ◽

Liquid Crystal Display ◽

Twisted Nematic ◽

Twisted Nematic Liquid Crystal ◽

Polarization States

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Investigation of alignment direction in wide view film and rubbing angle of twisted nematic liquid crystal display mode

Liquid Crystals ◽

10.1080/02678290903026445 ◽

2009 ◽

Vol 36 (5) ◽

pp. 487-492 ◽

Cited By ~ 6

Author(s):

Ji Ma ◽

Shawn Hurley ◽

Zhigang Zheng ◽

Bo Jin ◽

Deng-Ke Yang

Keyword(s):

Liquid Crystal ◽

Nematic Liquid Crystal ◽

Liquid Crystal Display ◽

Display Mode ◽

Twisted Nematic ◽

Twisted Nematic Liquid Crystal

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Product Review: High Dynamic Range Displays

Presence Teleoperators & Virtual Environments ◽

10.1162/pres.16.1.119 ◽

2007 ◽

Vol 16 (1) ◽

pp. 119-122 ◽

Cited By ~ 1

Author(s):

Patrick Ledda

Keyword(s):

Dynamic Range ◽

Liquid Crystal Display ◽

Contrast Ratio ◽

Luminance Level ◽

High Dynamic Range ◽

Natural World ◽

Adaptation Level ◽

Wide Range ◽

High Dynamic ◽

3D Software

In the natural world, the human eye is confronted with a wide range of colors and luminances. A surface lit by moonlight might have a luminance level of around 10−3 cd/m2, while surfaces lit during a sunny day could reach values larger than 105 cd/m2. A good quality CRT (cathode ray tube) or LCD (liquid crystal display) monitor is only able to achieve a maximum luminance of around 200 to 300 cd/m2 and a contrast ratio of not more than two orders of magnitude. In this context the contrast ratio or dynamic range is defined as the ratio of the highest to the lowest luminance. We call high dynamic range (HDR) images, those images (or scenes) in which the contrast ratio is larger than what a display can reproduce. In practice, any scene that contains some sort of light source and shadows is HDR. The main problem with HDR images is that they cannot be displayed, therefore although methods to create them do exist (by taking multiple photographs at different exposure times or using computer graphics 3D software for example) it is not possible to see both bright and dark areas simultaneously. (See Figure 1.) There is data that suggests that our eyes can see detail at any given adaptation level within a contrast of 10,000:1 between the brightest and darkest regions of a scene. Therefore an ideal display should be able to reproduce this range. In this review, we present two high dynamic range displays developed by Brightside Technologies (formerly Sunnybrook Technologies) which are capable, for the first time, of linearly displaying high contrast images. These displays are of great use for both researchers in the vision/graphics/VR/medical fields as well as professionals in the VFX/gaming/architectural industry.

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