METHODS FOR DRIVING VIDEO ELECTRO-OPTIC DISPLAYS

• US 20080291129A1
• Filed: 05/21/2008
• Published: 11/27/2008
• Est. Priority Date: 05/21/2007
• Status: Active Grant

• Current Assignee: E Ink Corporation (E Ink Holdings Incorporated)
• Original Assignee: E Ink Corporation (E Ink Holdings Incorporated)
• Inventors: Patry, Shamus Ford, Harris, George G., McCreary, Michael D.
• Granted Patent: US 10,319,313 B2
• Time in Patent Office: Days
• US Class Current: 345/60
• CPC Class Codes: G09G 2310/02 Addressing, scanning or driving the display screen or processing steps related thereto
• CPC Class Codes: G09G 2310/0216 Interleaved control phases for different scan lines in the same sub-field, e.g. initialization, addressing and sustaining in plasma displays that are not simultaneous for all scan lines
• CPC Class Codes: G09G 2320/0247 Flicker reduction other than flicker reduction circuits used for single beam cathode-ray tubes
• CPC Class Codes: G09G 2340/0435 Change or adaptation of the frame rate of the video stream
• CPC Class Codes: G09G 2340/16 Determination of a pixel data signal depending on the signal applied in the previous frame
• CPC Class Codes: G09G 3/2011 by amplitude modulation
• 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

Video displays using relatively low frame rates of about 10 to about 20 frames per second, but having acceptable video quality are described. The displays may use bistable media, and may be driven such that the medium, when driven, changes its optical properties continuously during the driving of each frame. The displays may use an electro-optic medium such that the frame period is from about 50 to about 200 percent of the switching time of the electro-optic medium at the driving voltage used.

Claims

1. A bistable electro-optic display arranged to display video at a frame rate of from about 10 to about 20 frames per second.

2. A display according to claim 1 arranged to display video at a frame rate of from about 13 to about 20 frames per second.

3. A display according to claim 1 comprising a rotating bichromal member or electrochromic electro-optic material.

4. A display according to claim 1 comprising an electrophoretic material, which itself comprises a plurality of electrically charged particles disposed in a fluid and capable of moving through the fluid under the influence of an electric field.

5. A display according to claim 4 wherein the electrically charged particles and the fluid are confined within a plurality of capsules or microcells.

6. A display according to claim 4 wherein the electrically charged particles and the fluid are present as a plurality of discrete droplets surrounded by a continuous phase comprising a polymeric material.

7. A display according to claim 4 wherein the fluid is gaseous.

24. An electronic book reader, portable computer, tablet computer, cellular telephone, smart card, sign, watch, shelf label or flash drive comprising a display according to claim 1.

8. A method of driving an electro-optic display, the method comprising driving the display at a frame rate of from about 10 to about 20 frames per second, wherein the electro-optic medium used in the display, when being driven, changes its electro-optic properties continuously throughout the driving of each frame.

9. A method according to claim 8 wherein the electro-optic medium, when being driven, changes its electro-optic properties substantially linearly throughout the driving of each frame.

10. A method according to claim 8 wherein the frame rate is from about 13 to about 20 frames per second.

11. A method according to claim 8 wherein the electro-optic medium comprises a rotating bichromal member or electrochromic medium.

12. A method according to claim 8 wherein the electro-optic medium comprises an electrophoretic medium, which itself comprises a plurality of electrically charged particles disposed in a fluid and capable of moving through the fluid under the influence of an electric field.

13. A method according to claim 12 wherein the electrically charged particles and the fluid are confined within a plurality of capsules or microcells.

14. A method according to claim 12 wherein the electrically charged particles and the fluid are present as a plurality of discrete droplets surrounded by a continuous phase comprising a polymeric material.

15. A method according to claim 12 wherein the fluid is gaseous.

16. A method of driving an electro-optic display comprising an electro-optic medium wherein the frame period is from about 50 to about 200 percent of the switching time of the electro-optic medium.

17. A method according to claim 16 wherein the frame period is from about 75 to about 150 percent of the switching time.

18. A method according to claim 16 wherein the electro-optic medium is bistable.

19. A method according to claim 18 wherein the electro-optic medium comprises a rotating bichromal member or electrochromic medium.

20. A method according to claim 18 wherein the electro-optic medium comprises an electrophoretic medium, which itself comprises a plurality of electrically charged particles disposed in a fluid and capable of moving through the fluid under the influence of an electric field.

21. A method according to claim 20 wherein the electrically charged particles and the fluid are confined within a plurality of capsules or microcells.

22. A method according to claim 20 wherein the electrically charged particles and the fluid are present as a plurality of discrete droplets surrounded by a continuous phase comprising a polymeric material.

23. A method according to claim 20 wherein the fluid is gaseous.