Color electrophoretic display

• US 8,797,635 B2
• Filed: 03/07/2012
• Issued: 08/05/2014
• Est. Priority Date: 06/28/2011
• Status: Active Grant

• Current Assignee: E Ink Holdings Incorporated
• Original Assignee: E Ink Holdings Incorporated
• Inventors: Yeh, Chia-Chun, Wang, Henry, Shinn, Ted-Hong, Jiang, Chi-Sheng
• Primary Examiner(s): Collins, Darryl J
• Assistant Examiner(s): O'NEILL, GARY WILLIAM
• Application Number:
  US13/414,694
• Publication Number:
  US 20130003165A1
• Time in Patent Office: 881 Days
• Field of Search: 359237-324, 345/107
• US Class Current: 359/296
• CPC Class Codes: G02F 1/167 by electrophoresis
• CPC Class Codes: G02F 1/1676 Electrodes
• CPC Class Codes: G02F 1/1677 Structural association of cells with optical devices, e.g. reflectors or illuminating devices
• CPC Class Codes: G02F 2201/50 Protective arrangements

Abstract

A color electrophoretic display includes a substrate, a segment electrode circuit layer, a transparent electrode layer, an electrophoretic display medium layer, and a colored polymer film. The segment electrode circuit layer is disposed on the substrate and is configured to display a letter and/or a pattern. The transparent electrode layer is disposed opposing the segment electrode circuit layer, and the electrophoretic display medium layer is disposed between the segment electrode circuit layer and the transparent electrode layer. The electrophoretic display medium layer is controlled by an electric field that is produced and varied by the segment electrode circuit layer and the transparent electrode layer to change brightness. The color polymer film is disposed on the transparent electrode layer to produce color. The colored polymer film includes a polymer layer and pigment particles distributed in the polymer layer.

Claims

1. A color electrophoretic display, having an inner display region and an outer display region extending from an edge of the color electrophoretic display to the inner display region, the outer display region encircling and adjoining the inner display region, the color electrophoretic display comprising:

a substrate;

a segment electrode circuit layer disposed on the substrate and configured to display a first symbol within the inner display region and a second symbol within the outer display region;

a transparent electrode layer disposed opposing the segment electrode circuit layer;

an electrophoretic display medium layer disposed between the segment electrode circuit layer and the transparent electrode layer, wherein the electrophoretic display medium layer is controlled by an electric field that is produced and varied by the segment electrode circuit layer and the transparent electrode layer to change brightness; and

a colored polymer protection film disposed on the transparent electrode layer, and comprising;

a middle part including a plurality of first pigment particles dispersed among the middle part and configured to show a first background color of the first symbol within the inner display region; and

a peripheral part including a plurality of second pigment particles dispersed among the peripheral part that extends from an edge of the colored polymer protection film to the middle area, the peripheral part encircling and adjoining the middle part, the second pigment particles configured to show a second background color of the second symbol within the outer display region.

2. The color electrophoretic display as claimed in claim 1, further comprising an adhesive layer adhered to the segment electrode circuit layer for protecting the segment electrode circuit layer.

3. The color electrophoretic display as claimed in claim 1, wherein the transparent electrode layer has a first surface and a second surface opposite the first surface and facing the electrophoretic display medium layer, and the colored polymer protection film is disposed on the first surface of the transparent electrode layer.

4. The color electrophoretic display as claimed in claim 1, wherein the first pigment particles are evenly distributed in the middle part of the colored polymer protection film such that the middle part of colored polymer protection film evenly presents the first background color, and the second pigment particles are evenly distributed in the peripheral part of the colored polymer protection film such that the peripheral part of colored polymer protection film evenly presents the second background color that is different from the first background color.

5. The color electrophoretic display as claimed in claim 1, wherein each of the first pigment particles has a color of red, orange, yellow, green, blue, indigo, or purple, and each of the second pigment particles has a color of red, orange, yellow, green, blue, indigo, or purple.

6. The color electrophoretic display as claimed in claim 1, wherein the first pigment particles include a plurality of red particles, a plurality of green particles, and a plurality of blue particles.

7. The color electrophoretic display as claimed in claim 1, wherein the colored polymer protection film comprises a multilayer polymer film including a color film adhered to a colorless polymer film.

8. The color electrophoretic display as claimed in claim 1, wherein the colored polymer protection film is doped with phosphor for use as a light source.

9. The color electrophoretic display as claimed in claim 1, wherein the colored polymer protection film is an anti-glare film, an antireflection film;

an ultraviolet light blocking film, a water blocking film, or an anti-scratch film.

10. The color electrophoretic display as claimed in claim 1, wherein the electrophoretic display medium layer is a microcapsule-type electrophoretic display medium layer, a micro-cup electrophoretic display medium layer, or an electronic liquid powder electrophoretic display medium layer.

11. The color electrophoretic display as claimed in claim 1, wherein the substrate is a glass substrate, a plastic substrate, or a flexible substrate.

12. The color electrophoretic display as claimed in claim 1, wherein the segment electrode circuit layer comprises seven of the segment electrodes provided in the form of a seven-segment display.

13. A color electrophoretic display, comprising:

a substrate having a first region and a second region surrounding the first region;

a segment electrode circuit layer disposed on the substrate, wherein the segment electrode circuit layer occupies the first region for showing a visible pattern, and the second region is not occupied by the segment electrode circuit layer;

a transparent electrode layer disposed opposing the segment electrode circuit layer;

an electrophoretic display medium layer disposed between the segment electrode circuit layer and the transparent electrode layer, wherein the electrophoretic display medium layer is controlled by an electric field that is produced and varied by the segment electrode circuit layer and the transparent electrode layer; and

a colored polymer protection film disposed on the transparent electrode layer, and comprising;

a first portion overlapped with the segment electrode circuit layer on the first region, and

a second portion surrounding the first portion and extended from an edge of the colored polymer protection film to the first portion, wherein the second portion has a plurality of pigment particles dispersed among the second portion for showing a background color of the visible pattern, and is not overlapped with the segment electrode circuit layer on the first region when viewed in a direction perpendicular to the substrate.