Polymer stabilized black-white cholesteric reflective display

Abstract

Abstract 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. This embodiment allows for a display with a substantially white background with substantially black characters much like a printed page. In yet another embodiment, the application of mechanical force to the cell changes the material from an optically clear state to a light reflecting state.

Inventors

• 👤 Deng-Ke Yang
• 👤 Ruiqing Ma

Bibliographic Details