ELECTRO-OPTIC DISPLAYS

• US 20120293858A1
• Filed: 05/18/2012
• Published: 11/22/2012
• Est. Priority Date: 05/21/2011
• Status: Active Grant

• Current Assignee: E Ink Holdings Incorporated
• Original Assignee: E Ink Holdings Incorporated
• Inventors: Telfer, Stephen J., Paolini, Richard J. Jr., McCreary, Michael D., Cole, David John
• Granted Patent: US 10,372,008 B2
• Time in Patent Office: Days
• US Class Current: 359/296
• CPC Class Codes: G02F 1/167 by electrophoresis
• CPC Class Codes: G02F 1/16757 Microcapsules
• CPC Class Codes: G02F 2201/343 cholesteric liquid crystal reflector

Abstract

A wavelength selective reflection display (10) comprises a wavelength selective reflection medium (20) and a backing member (30) having a first, non-reflective optical state, and a second, reflective optical state. Both the wavelength selective reflection medium (20) and the backing member (30) are divided into pixels (40, 50, 60), and the backing member (30) is switchable between its first and second optical states on a pixel-by-pixel basis. The pixels of the backing member (30) are substantially aligned with those of the wavelength selective reflection medium (20).

Claims

1. A wavelength selective reflection (WSR) display comprising a wavelength selective reflection medium having a plurality of pixels and, disposed adjacent the wavelength selective reflection medium, a backing member having a plurality of pixels and having a first, non-reflective optical state, and a second, reflective optical state, the backing member being switchable between its first and second optical states on a pixel-by-pixel basis, the pixels of the backing member being substantially aligned with the pixels of the wavelength selective reflection medium.

2. A WSR display according to claim 1 wherein the backing member has at least one intermediate gray level having a reflectivity intermediate its first and second optical states.

3. A WSR display according to claim 1 wherein the backing member comprises a variable medium having a reflective state and a substantially light-transmissive state, and a non-varying dark surface disposed on the opposed side of the variable medium from the WSR medium.

4. A WSR display according to claim 1 wherein the backing member comprises a variable medium having a non-reflective state and a substantially light-transmissive state, and a non-varying reflective surface disposed on the opposed side of the variable medium from the WSR medium.

5. A WSR display according to claim 1 wherein the backing member comprises a variable medium having reflective, non-reflective and light-transmissive states.

6. A WSR display according to claim 5 further comprising a light source disposed on the opposed side of the variable medium from the WSR medium.

7. A WSR display according to claim 1 wherein the backing member comprises a layer of electro-optic material capable of being switched between a reflective state and a non-reflective or transmissive optical state.

8. A WSR display according to claim 7 wherein the electro-optic material comprises a rotating bichromal member, electrochromic or electro-wetting material.

9. A WSR display according to claim 7 wherein the electro-optic material comprises an electrophoretic material comprising a plurality of electrically charged particles disposed in a fluid and capable of moving through the fluid under the influence of an electric field.

10. A WSR display according to claim 9 wherein the electrically charged particles and the fluid are confined within a plurality of capsules or microcells.

11. A WSR display according to claim 9 wherein the electrically charged particles and the fluid are present as a plurality of discrete droplets surrounded by a continuous phase comprising a polymeric material.

12. A WSR display according to claim 9 wherein the fluid is gaseous.

13. A WSR display according to claim 1 wherein the WSR medium is an electrically-addressable photonic crystal.