Color display devices

• US 8,169,690 B2
• Filed: 02/12/2009
• Issued: 05/01/2012
• Est. Priority Date: 02/21/2008
• Status: Active Grant

• Current Assignee: E Ink Holdings Incorporated
• Original Assignee: SiPix Imaging, Inc. (E Ink Holdings Incorporated)
• Inventors: Lin, Craig, Sprague, Robert A.
• Primary Examiner(s): Mack, Ricky
• Assistant Examiner(s): Patel, Vipin
• Application Number:
  US12/370,485
• Publication Number:
  US 20090213452A1
• Time in Patent Office: 1,174 Days
• Field of Search: 359294-297
• US Class Current: 359/296
• CPC Class Codes: G02F 1/133504 Diffusing, scattering, diffracting elements associated to illuminating devices G02F1/133606
• CPC Class Codes: G02F 1/133512 Light shielding layers, e.g. black matrix G02F1/136209 takes precedence
• CPC Class Codes: G02F 1/167 by electrophoresis
• CPC Class Codes: G02F 1/1677 Structural association of cells with optical devices, e.g. reflectors or illuminating devices
• CPC Class Codes: G02F 1/1681 having two or more microcells partitioned by walls, e.g. of microcup type
• CPC Class Codes: G02F 2203/34 Colour display without the use of colour mosaic filters

Abstract

The present invention is directed to color display devices. The color display devices comprise display cells which is capable of displaying multiple color states. The display device may also comprise black matrix layers or a brightness enhancement structure on the viewing side. The present invention is directed to a display device comprising a plurality of display cells, wherein each of said display cells is sandwiched between a first layer comprising a common electrode and a second layer comprising a plurality of driving electrodes and at least one of the driving electrodes is a designated electrode, and said display device further comprises blocking layers on its viewing side and said blocking layers are located in positions corresponding to the designated electrodes.

Claims

1. A display device comprising a plurality of display cells filled with a display fluid comprising charged pigment particles dispersed in a solvent or solvent mixture, wherein each of said display cells is sandwiched between a first layer comprising a transparent common electrode and a second layer comprising a plurality of driving electrodes and at least one of the driving electrode is a designated electrode, and said display device further comprises blocking layers on its viewing side and said blocking layers are located only in positions corresponding to the designated electrodes to allow the charged pigment particles gathered at or near the designated electrode not to be seen from the viewing side.

2. The display device of claim 1, wherein said blocking layers are black matrix layers.

3. The display device of claim 2, wherein the width of the black matrix layer is equal to or greater than the width of the designated electrode.

4. The display device of claim 1, wherein said blocking layers are micro-structures or micro-reflectors of a brightness enhancement structure.

5. The display device of claim 4, wherein the width of the base of the micro-structure or micro-reflector is equal to or greater than the width of the designated electrode.

6. The display device of claim 4, wherein said brightness enhancement structure is two-dimensional.

7. The display device of claim 4, wherein said brightness enhancement structure is one-dimensional.

8. The display device of claim 1, wherein each display cell is capable of displaying the color of the charged pigment particles, the color of the solvent or solvent mixture or a background color.

9. The display device of claim 8, wherein the background color is of the black color.

10. The display device of claim 1, wherein said driving electrodes are not aligned with the boundary of the display cells.

11. The display device of claim 1, wherein said driving electrodes are aligned with the boundary of the display cells.

12. The display device of claim 1, wherein the charged pigment particles move to the designated electrode(s) all at once.

13. The display device of claim 1, wherein the charged pigment particles move to the designated electrode(s) in steps.

14. The display device of claim 1, wherein the charged pigment particles are of the white color.

15. The display device of claim 1, further comprising color filters.

16. The display device of claim 15, wherein said charged pigment particles are of the white color.

17. The display device of claim 15, wherein said charged pigment particles are of the black color.

18. The display device of claim 1, wherein said driving electrodes are a grid of at least 2×

2.

19. The display device of claim 1, wherein the first layer is on the viewing side.

20. The display device of claim 1, wherein some of the driving electrodes are connected as one non-designated electrode and the remaining one driving electrode is the designated electrode.

21. The display device of claim 1, wherein some of the driving electrodes are connected as one non-designated electrode and the remaining driving electrodes are connected as one designated electrode.

22. A display device, which

(a) comprises a plurality of display cells filled with a display fluid comprising charged pigment particles dispersed in a solvent or solvent mixture and a background layer on the non-viewing side, wherein each of said display cells is sandwiched between a first layer comprising a common electrode and a second layer comprising a plurality of driving electrodes, at least one of the driving electrodes is a non-transparent designated electrode, and the remaining driving electrodes are transparent;

and

(b) is viewed from the side of the second layer and the color of the background layer is seen when the charged pigment particles migrate to gather at or near the non-transparent designated electrode.

23. The display device of claim 22, wherein said non-transparent designated electrode is opaque.