Electrostatically addressable electrophoretic display

• US 7,352,353 B2
• Filed: 12/05/2003
• Issued: 04/01/2008
• Est. Priority Date: 07/20/1995
• Status: Expired due to Fees

• Current Assignee: E Ink Corporation (E Ink Holdings Incorporated)
• Original Assignee: E Ink Corporation (E Ink Holdings Incorporated)
• Inventors: Comiskey, Barrett, Albert, Jonathan D.
• Primary Examiner(s): LEWIS, DAVID LEE
• Application Number:
  US10/729,044
• Publication Number:
  US 20040113884A1
• Time in Patent Office: 1,579 Days
• Field of Search: 345/107, 349/57, 359/296
• US Class Current: 345/107
• CPC Class Codes: B82Y 20/00 Nanooptics, e.g. quantum optics or photonic crystals
• CPC Class Codes: G02F 1/167 by electrophoresis
• CPC Class Codes: G02F 1/1685 Operation of cells; Circuit arrangements affecting the entire cell
• CPC Class Codes: G06F 15/0283 for data storage and retrieval
• CPC Class Codes: G09G 2300/0426 Layout of electrodes and connections
• CPC Class Codes: G09G 2300/0434 Flat panel display in which a field is applied parallel to the display plane
• 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
• CPC Class Codes: H05K 1/097 Inks comprising nanoparticles and specially adapted for being sintered at low temperature H05K1/095 takes precedence
• CPC Class Codes: H05K 3/105 by conversion of non-conductive material on or in the support into conductive material, e.g. by using an energy beam
• CPC Class Codes: H05K 3/1241 by ink-jet printing or drawing by dispensing

Abstract

Novel addressing schemes for controlling electronically addressable displays include a scheme for rear-addressing displays, which allows for in-plane switching of the display material. Other schemes include a rear-addressing scheme which uses a retroreflecting surface to enable greater viewing angle and contrast. Another scheme includes an electrode structure that facilitates manufacture and control of a color display. Another electrode structure facilitates addressing a display using an electrostatic stylus. Methods of using the disclosed electrode structures are also disclosed. Another scheme includes devices combining display materials with silicon transistor addressing structures.

Claims

1. An electrostatically addressable display, comprising:

(a) a substrate;

(b) an encapsulated electrophoretic display medium disposed adjacent said substrate, said electrophoretic display medium comprising a plurality of cavities dispersed in a polymeric matrix, wherein at least one of said plurality of cavities contains an electrophoretic contrast media phase that includes at least one particle and a suspending fluid; and

(c) a movable electrode,

wherein application of electrostatic charge by said movable electrode to said electrophoretic display medium modulates an optical property of said electrophoretic display medium.

2. The display of claim 1, wherein said substrate further comprises a clear conductive coating.

3. The display of claim 2, wherein said clear conductive coating comprises an ITO-coated polyester.

4. The display of claim 2, wherein the clear conductive coating is connected to ground potential.

5. The display of claim 2, further comprising a dielectric sheet disposed adjacent said electrophoretic display medium.

6. The display of claim 5, wherein said dielectric sheet further comprises a coating having low conductivity.

7. The display of claim 1, wherein said substrate further comprises an opaque conductive coating.

8. The display of claim 1, wherein said movable electrode comprises a stylus.

9. The display of claim 1, wherein no capsule membrane is present between said electrophoretic contrast media phase and said polymeric matrix.

10. A method of addressing an electrostatically addressable display, comprising:

providing an electrostatically addressable display, comprising;

a substrate,

an electrophoretic display medium disposed adjacent said substrate, said electrophoretic display medium comprising a plurality of cavities dispersed in a polymeric matrix, wherein at least one of said plurality of cavities contains an electrophoretic contrast media phase that includes at least one particle and a suspending fluid, and

a movable electrode; and

applying an electrostatic charge from said movable electrode to said electrophoretic display medium to modulate an optical property of said electrophoretic display medium.

11. The method of claim 10, further comprising the step of scanning said movable electrode over said electrophoretic display medium.

12. The method of claim 11, wherein the step of scanning said movable electrode over said electrophoretic display medium is performed substantially contemporaneously with the step of applying an electrostatic charge from said movable electrode to said electrophoretic display medium.

13. The method of claim 10, wherein the step of scanning said movable electrode over said electrophoretic display medium and the step of applying an electrostatic charge from said movable electrode to said electrophoretic display medium are performed sequentially.

14. The method of claim 10, wherein no capsule membrane is present between said electrophoretic contrast media phase and said polymeric matrix.