Kent State University

Toyota Motor Engineering & Manufacturing North America, Inc.

Mirise Technology Corporation

Universal Display Corporation

Deng-Ke Yang

J William Doane

Liang-Chy Chien

Sean P Rodrigues

Yunho Shin

Guangkui Qin

John L West

Philip J Bos

Xiao-Yang Huang

Yue Cui

Zhijian Lu

Yingfei Jiang

Suman Halder

Gregory Mcgraw

Various arrangements described herein relate to a dual-sided display with improved light scattering. In one embodiment, a display is disclosed. The display includes an inside transparent layer disposed parallel to and spaced apart from an outside transparent layer. The display also includes a liquid crystal (LC) layer disposed between the inside transparent layer and the outside transparent layer and together forming a waveguide that is planar. The display includes ground electrodes disposed between the LC layer and the outside transparent layer and arranged in strips along the transparent layer, the strips being spaced apart and parallel. The display includes inside electrodes and outside electrodes disposed between the inside transparent layer and the LC layer and defining a geometric pattern that is in plane with the waveguide and a light source disposed at an edge surface of the waveguide and providing light along the waveguide.

Dual-sided waveguide display with improved light scattering

A dual-mode switchable liquid-crystal window can control both radiant energy flow and privacy. The modes are selected by using different voltage frequencies. A dichroic dye is doped to enable modulation of transmission of the window. In the absence of an applied voltage, the window is transparent without haze. When a high-frequency (e.g., 1 kHz) voltage is applied, the liquid crystal and doped dye molecules inside the window reorient uniformly under dielectric interactions. The material becomes optically absorbing. The transmittance decreases, but the haze does not change. In this mode, the window can control radiant energy flow through the window. When a low-frequency (50 Hz) voltage is applied, the liquid crystal and doped dye molecules are switched into a micron-sized polydomain structure under flexoelectric interactions. The material becomes optically scattering and absorbing. The scenery behind the window is blocked. In this mode, privacy can be controlled. This dual-mode switchable window is suitable for architectural and automobile windows.

Dual-mode smart switchable liquid crystal window

A dual side view display includes a waveguide with an inside transparent layer and an outside transparent layer spaced apart from and parallel to the inside transparent layer, and a plurality of inside view liquid crystal (LC) pixels and a plurality of outside view LC pixels disposed within the waveguide. The plurality of outside view LC pixels are disposed within the waveguide parallel to and in-plane with the plurality of inside view LC pixels. The plurality of inside LC pixels includes a plurality of outside blocking layers configured to block light scattered in the plurality of inside view LC pixels from propagating through the outside transparent layer. Also, the plurality of outside view LC pixels includes a plurality of inside blocking layers configured to block light scattered in the plurality of outside view LC pixels from propagating through the inside transparent layer.

Dual side view waveguide liquid crystal displays

Polymer/cholesteric liquid crystal dispersions are provided in which the liquid crystal phase separated from the polymer matrix to form droplets. The cholesteric liquid crystals were positive dielectric anisotropic. At a zero field condition, the liquid crystal in the droplets was bistable, that is, the liquid crystal can be in either the reflecting planar state or the scattering focal conic state. When the liquid crystal 101 was in the planar texture, the helical axis of the liquid crystal was more or less perpendicular to the cell surface; colored light 105 was Bragg reflected. When the liquid crystal 101 was in the focal conic texture, the helical axis was more or less parallel to the cell surface, incident light was scattering 106 in the forward direction.

Bistable polymer dispersed cholesteric liquid crystal displays

A flat-panel liquid crystal display. The display includes a flat sheet of bistable chiral nematic liquid crystal material activated by a drive circuit that individually controls the display state of multiple picture elements at a refresh rate 1000 scan lines per second. The driver circuitry activates the liquid crystal domains into homeotropic states over a relatively long activation period and then, during a short (.about.1 msec.) selection period, either keeps the domains in a homeotropic state or initiate a transition to the transient twisted planar state. The drivers then activate the domains in an evolution phase to provide either focal conic or twisted planar end states across the two-dimensional array of picture elements.

Dynamic drive method and apparatus for a bistable liquid crystal display

A new liquid crystalline light modulating cell and material are characterized by liquid crystalline light modulating material of liquid crystal and polymer, the liquid crystal being a chiral nematic liquid crystal having positive dielectric anisotropy and including chiral material in an amount effective to form focal conic and twisted planar textures, the polymer being distributed in phase separated domains in the liquid crystal cell in an amount that stabilizes the focal conic and twisted planar textures in the absence of a field and permits the liquid crystal to change textures upon the application of a field. In one embodiment, the material is light scattering in a field-OFF condition and optically clear in a field-ON condition, while in another embodiment, the material is optically clear in a field-OFF condition and light scattering in a field-ON condition. In still another embodiment, the material exhibits stability at zero field in a colored, light reflecting state, a light scattering state and multiple stable reflecting state therebetween, as well as being optically clear in the presence of a field.

Liquid crystalline light modulating device and material

Polymer stabilized liquid crystalline light modulating device and

A light modulating reflective cell comprising a polymer-free chiral nematic liquid crystalline light modulating material is disclosed. The cell includes nematic liquid crystal having positive dielectric anisotropy and chiral material in an amount effective to form focal conic and twisted planar textures. The chiral material has a pitch length effective to reflect light in the visible spectrum, wherein the focal conic and twisted planar textures are stable in the absence of a field and the liquid crystal material is capable of changing textures upon the application of a field.

Multistable chiral nematic displays

A light modulating apparatus comprising a liquid crystal light modulating material confined between substrates, elongated electrically-conductive paths supported on opposite sides of the light modulating material by the substrates and a pair of gating systems for supplying voltage pulses to the electrically conductive paths for addressing the light modulating material is disclosed. The light modulating material includes polydomains of polymer network dispersed in a chiral nematic liquid crystal having positive dielectric anisotropy. This material is confined by the substrates between inner surfaces treated to promote homogeneous alignment of the liquid crystal near the inner surfaces. The apparatus provides energy efficient passive control of a bistable light modulating material.

Growing community of inventors

Kent, OH, United States of America

Deng-Ke Yang