Reusable display addressable with incident light

Patent metadata

Field	Value
Publication number	US-2020004098-A1
Application number	US-201916564036-A
Country	US
Kind code	A1
Filing date	Sep 9, 2019
Priority date	Aug 4, 2015
Publication date	Jan 2, 2020
Grant date	—

Abstract

A reflective color display that can be addressed from the front (viewing surface side) of the display with a light source, such as a projector, LED, or laser. The display comprises (in order) a color filter array, a transparent electrode, an electro-optic medium, a photoconductive material, and a rear electrode. The color displays of the invention are useful for large format color signage, such as billboards and wayfinding.

First claim

1 . A method for displaying a reflective image, comprising:
providing a display including, a color filter array, a transparent electrode, an electro-optic medium, a photoconductive material, and a rear electrode; supplying a first electrical potential between the transparent electrode and the rear electrode; and exposing the display to a source of patterned light.

2 . The method of claim 1 , further comprising supplying a second electrical potential to remove the reflective image.

3 . The method of claim 1 , wherein the source of patterned light comprises a projector.

4 . The method of claim 1 , wherein the electrical potential is a time-dependent wave form.

5 . The method of claim 1 , wherein the electro-optic medium 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.

6 . The method of claim 5 , wherein the electrically charged particles are white and black.

7 . The method of claim 1 , wherein the color filter array comprises red, green, and blue elements.

8 . The method of claim 7 , wherein the red, green, and blue elements are smaller than 1 mm 2 in area.

9 . The method of claim 7 , wherein the red, green, and blue elements are greater than 1 mm 2 in area.

10 . The method of claim 1 , wherein the photoconductive material comprises photoconductive polymers, dye-aggregate photoreceptors, or pigment-based photoconductors.

11 . The method of claim 1 , wherein the photoconductive material comprises 2,4,7-trinitro-9-fluorine complexed with poly(N-vinylcarbazole).

12 . A system for providing a reflective image, comprising:
a display including, a color filter array, a transparent electrode, an electro-optic medium, a photoconductive material, and a rear electrode; a voltage supply for providing an electrical potential between the transparent electrode and the rear electrode; and a controller for regulating the electrical potential.

13 . The system of claim 12 , further comprising an illumination source for the display.

14 . The system of claim 13 , wherein the illumination source is a projector.

15 . The method of claim 1 , wherein the electro-optic medium 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.

16 . A system for providing a reflective image, comprising:
a display including,
a color filter array,
a transparent electrode,
an electro-optic medium, and
a photoconductive material;
an electrode configured to provide an electrical potential suitable for addressing a portion of the display with light; and an illumination source configured to illuminate a portion of the display with light to address the display.

17 . The system of claim 16 , wherein the illumination source produces light outside of the visible spectrum.

18 . The system of claim 16 , further comprising a light filter that passes visible light.

19 . The system of claim 16 , wherein the electro-optic medium 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.

Assignees

• E Ink Corp

Inventors

• Harris George G
• Paolini Jr Richard J

Classifications

• G02B5/201

  in the form of arrays · CPC title

• G02F1/1676

  Electrodes · CPC title

• G02F2202/12

  photoconductor · CPC title

• G02F1/1336

  Illuminating devices · CPC title

• G02F1/167 Primary

  by electrophoresis · CPC title