Color display architecture and driving methods

• US 8,704,756 B2
• Filed: 05/25/2011
• Issued: 04/22/2014
• Est. Priority Date: 05/26/2010
• Status: Active Grant

• Current Assignee: E Ink Holdings Incorporated
• Original Assignee: SiPix Imaging, Inc. (E Ink Holdings Incorporated)
• Inventors: Lin, Craig
• Primary Examiner(s): GIESY, ADAM
• Application Number:
  US13/115,899
• Publication Number:
  US 20110292094A1
• Time in Patent Office: 1,063 Days
• Field of Search: 345/107
• US Class Current: 345/107
• CPC Class Codes: G02F 2001/1678 characterised by the composition or particle type
• CPC Class Codes: G02F 2203/34 Colour display without the use of colour mosaic filters
• CPC Class Codes: G09G 3/344 based on particles moving in a fluid or in a gas, e.g. electrophoretic devices electrophoretic devices per se G02F1/167

Abstract

A method for driving a display cell filled with an electrophoretic fluid comprising two types of pigment particles carrying opposite charge polarities and of two contrast colors wherein said two types of pigment particles are dispersed in a solvent of a color, which method comprises driving said display cell to a color state which color is the color of the solvent by applying a driving voltage which is about 1 to about 20% of the full driving voltage.

Claims

1. A method for driving a color display comprising display cells sandwiched between a common electrode and pixel electrodes, wherein each of the display cells is filled with an electrophoretic fluid comprising two types of pigment particles dispersed in a solvent of a color, wherein the two types of pigment particles carry opposite charge polarities and are of two contrast colors;

the method comprises applying a driving voltage between the common electrode and a pixel electrode to drive the electrophoretic fluid in an area corresponding to the pixel electrode to a color state in which a displayed color is the color of the solvent, wherein the driving voltage is 1 to 20% of a full driving voltage required to drive the two types of pigment particles to be near or at the common electrode or the pixel electrodes.

2. The method of claim 1, wherein said two types of pigment particles are white and black pigment particles carrying opposite charge polarities.

3. The method of claim 1, wherein the color of the solvent is red, green or blue.

4. The method of claim 1, wherein the two types of pigment particles have different mobilities.

5. The method of claim 1, wherein the two types of pigment particles have similar mobility.

6. The method of claim 1, wherein said display cell is microcup based.

7. The method of claim 1, wherein said display cell is microcapsule based.

8. The method of claim 1, wherein said solvent is of the same color in all display cells.

9. The method of claim 1, wherein said solvent is of different colors in display cells.