Color display architecture and driving methods

• US 9,116,412 B2
• Filed: 03/03/2014
• Issued: 08/25/2015
• Est. Priority Date: 05/26/2010
• Status: Active Grant

• Current Assignee: E Ink Holdings Incorporated
• Original Assignee: E Ink California, LLC (E Ink Corporation)
• Inventors: Lin, Craig
• Primary Examiner(s): Ben, Loha
• Application Number:
  US14/195,679
• Publication Number:
  US 20140177031A1
• Time in Patent Office: 540 Days
• Field of Search: 359/228, 359/245, 359/253, 359/296, 345/76, 345/107, 345/211, 345/212, 345/690, 345/691, 204/600
• US Class Current: 1/1
• CPC Class Codes: G02B 26/00 Optical devices or arrangements for the control of light using movable or deformable optical elements control of light by modification of the optical properties of the media of the elements involved therein G02F1/00
• CPC Class Codes: G02B 26/02 for controlling the intensity of light G02B26/004 takes precedence
• CPC Class Codes: G02B 26/026 based on the rotation of particles under the influence of an external field, e.g. gyricons, twisting ball displays based on orientable dipolar particles G02F1/172; based on electrophoresis G02F1/167
• CPC Class Codes: G02F 1/167 by electrophoresis
• CPC Class Codes: G02F 1/1681 having two or more microcells partitioned by walls, e.g. of microcup type
• 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: G09F 9/372 the positions of the elements being controlled by the application of an electric field
• CPC Class Codes: G09G 2300/0439 Pixel structures
• CPC Class Codes: G09G 2320/0223 Compensation for problems related to R-C delay and attenuation in electrodes of matrix panels, e.g. in gate electrodes or on-substrate video signal electrodes
• CPC Class Codes: G09G 2320/0242 Compensation of deficiencies in the appearance of colours
• CPC Class Codes: G09G 3/34 by control of light from an independent source
• 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

The invention relates to a method for driving a display cell filled with an electrophoretic fluid comprising two types of charged particles carrying opposite charge polarities and of two contrast colors, wherein the two types of pigment particles are dispersed in a solvent of a color or in a solvent with non-charged or slightly charged colored particles dispersed therein. The method comprises driving said display cell to display the color of the solvent or the color of the non-charged or slightly charged colored particles 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 charged particles and one type of non-charged or slightly charged colored particles dispersed in a solvent, and the two types of charged particles carry opposite charge polarities and are of two contrast colors;

the method comprising 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 display the color of the non-charged or slightly charged colored particles, wherein the driving voltage is 1 to 20% of a full driving voltage required to drive the two types of charged particles to be near or at the common electrode or the pixel electrodes.

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

3. The method of claim 1, wherein the color of the non-charged or slightly charged colored particles is non-black and non-white.

4. The method of claim 1, wherein the color of the non-charged or slightly charged colored particles is red, green or blue.

5. The method of claim 1, wherein the two types of charged particles have different degrees of mobility.

6. The method of claim 1, wherein the two types of charged particles have similar mobility.

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

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

9. The method of claim 1, wherein color of the non-charged or slightly charged colored particles is the same color in all display cells.

10. The method of claim 1, wherein colors of the non-charged or slightly charged colored particles are different in display cells.