Electro-optic displays, and methods for driving same

• US 7,787,169 B2
• Filed: 03/23/2005
• Issued: 08/31/2010
• Est. Priority Date: 03/18/2002
• Status: Active Grant

• Current Assignee: E Ink Holdings Incorporated
• Original Assignee: E Ink Holdings Incorporated
• Inventors: Zehner, Robert W., Paolini, Richard J. Jr., Honeyman, Charles H., Abramson, Justin J., Cronin, John E., O'Neil, Steven J., Knaian, Ara N., Danner, Guy M., Duthaler, Gregg M., Zalesky, Jonathan L., Gates, Holly G., Amundson, Karl R., Wang, Jianna, Pullen, Anthony Edward, Morrison, Ian D.
• Primary Examiner(s): Stultz; Jessica T
• Application Number:
  US10/907,171
• Publication Number:
  US 20050152018A1
• Time in Patent Office: 1,987 Days
• Field of Search: 359264-277, 359252-255, 359/296, 359240-242, 359/245, 359/452, 359321-322, 359/307, 359/315, 252583-584, 252/586, 348/11, 348/105, 348 87- 88, 348/84, 348 48- 49, 348/102, 348107-108
• US Class Current: 359/267
• CPC Class Codes: G02F 1/1503 caused by oxidation-reduction reactions in organic liquid solutions, e.g. viologen solutions
• CPC Class Codes: G02F 1/1516 comprising organic material
• CPC Class Codes: G02F 2201/42 Arrangements for providing conduction through an insulating substrate

Abstract

The invention relates to electro-optic displays and methods for driving such displays. The invention provides (i) electrochromic displays with solid charge transport layers; (ii) apparatus and methods for improving the contrast and reducing the cost of electrochromic displays; (iii) apparatus and methods for sealing electrochromic displays from the outside environment and preventing ingress of contaminants into such a display; and (iv) methods for adjusting the driving of electro-optic displays to allow for environmental and operating parameters.

Claims

1. A method of operating an electro-optic display, the display comprising an electro-optic medium;

and at least one electrode arranged to apply an electric field to the electro-optic medium, the method comprising;

applying a first driving pulse to the electrode;

measuring the current passing through the electro-optic medium as a result of the application of the first driving pulse; and

applying a second driving pulse to the electrode, the second driving pulse being controlled by the measured current.

2. A method according to claim 1 further comprising measuring the temperature of the display and controlling the second driving pulse dependent upon the measured temperature and the measured current.

3. A method according to claim 1 further comprising measuring the ambient light level of the display and controlling the second driving pulse dependent upon the measured ambient light level and the measured current.

4. A method according to claim 1 further comprising controlling the second driving pulse dependent upon the age of the electro-optic medium and the measured current.

5. A method according to claim 1 wherein the electro-optic medium is an electrophoretic medium comprising a suspending fluid, and a plurality of electrically charged particles suspended in the suspending fluid and capable of moving therethrough on application of an electric field to the suspending fluid.

6. A method according to claim 5 wherein the suspending fluid and the plurality of electrically charged particles are retained within a plurality of capsules.

7. A method according to claim 5 wherein the suspending fluid and the plurality of electrically charged particles are present as a plurality of discrete droplets and a continuous phase of polymeric material surrounds the droplets.

8. A method according to claim 5 wherein the suspending fluid and the plurality of electrically charged particles are retained within a plurality of cavities formed in a carrier medium.

9. A method according to claim 1 wherein the electro-optic medium is a rotating bichromal member medium or an electrochromic medium.