Pen tracking and low latency display updates on electronic paper displays

• US 8,416,197 B2
• Filed: 03/31/2008
• Issued: 04/09/2013
• Est. Priority Date: 06/15/2007
• Status: Active Grant

• Current Assignee: E Ink Corporation (E Ink Holdings Incorporated)
• Original Assignee: Ricoh Company Limited
• Inventors: Feng, Guotong, Barrus, John W.
• Primary Examiner(s): Dharia, Prabodh M
• Application Number:
  US12/059,091
• Publication Number:
  US 20080309636A1
• Time in Patent Office: 1,835 Days
• Field of Search: 345 5- 25, 345/87, 345/89, 345105-108, 345/156, 345169-182, 345204-214, 345/626, 345/520, 345/419, 345/660, 345/690, 345/501, 345/536, 345/55, 345/545, 345/59, 455/556.1, 178 1801- 1809, 178 1901- 1905, 349/62
• US Class Current: 345/173
• CPC Class Codes: G09G 2310/04 Partial updating of the display screen
• 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 system and a method are disclosed for fast pen tracking a low latency display updates on an electronic paper display. Pen input information is received on an electronic paper display that updates at a predetermined display update rate. A line drawing module of the electronic paper display driver determines at least one pixel to activate based on the received pen input information. The at least one pixel is updated independent of the display update rate of the electronic paper display. Active pixel state information is maintained separately for each pixel in real time until the pixel update is complete and the pixel is deactivated. In some embodiments, a future pixel to activate is determined based on the received pen input information. The future pixel is deactivated if pen input information is not received on the activated pixel for a predetermined amount of time.

Claims

1. A method for activating pixels on an electronic paper display that updates at a predetermined display update rate, comprising:

receiving pen input information for at least one current pixel of the electronic paper display;

determining the at least one current pixel to activate based on the pen input information for the at least one current pixel;

activating the at least one current pixel of the electronic paper display independent of the display update rate of the electronic paper display;

predicting a direction of the pen input to determine at least one future pixel of the electronic paper display to activate based on the pen input information for the at least one current pixel;

activating the at least one future pixel based on the pen input information for the at least one current pixel; and

deactivating the activated future pixel after a predetermined amount of time in response to an absence of receiving pen input information for the activated future pixel.

2. The method of claim 1, further comprises activating the at least one future pixel by applying a voltage to the at least one future pixel.

3. The method of claim 2, further comprises deactivating the activated future pixel by reversing the applied voltage to the activated future pixel.

4. The method of claim 1, further comprising:

activating a region of the electronic paper display based on the pen input information for the at least one current pixel; and

deactivating the activated region of the electronic paper display in response to, after the predetermined amount of time, an absence of receiving pen input information for the activated region.

5. The method of claim 1, wherein the pen input information is received on a touch sensor display.

6. The method of claim 1, further comprising:

maintaining active pixel information for each current pixel.

7. The method of claim 6, wherein the maintaining active pixel information includes maintaining a display list for each current pixel.

8. The method of claim 6, wherein the maintaining active pixel information includes maintaining a frame counter for each current pixel.

9. A system for activating pixels on an electronic paper display that updates at a predetermined display update rate, comprising:

means for receiving pen input information for at least one current pixel of the electronic paper display;

means for determining the at least one current pixel to activate based on the pen input information for the at least one current pixel;

means for activating the at least one current pixel of the electronic paper display independent of the display update rate of the electronic paper display;

means for predicting a direction of the pen input to determine at least one future pixel of the electronic paper display to activate based on the pen input information for the at least one current pixel;

means for activating the at least one future pixel based on the pen input information for the at least one current pixel; and

means for deactivating the activated future pixel after a predetermined amount of time in response to an absence of receiving pen input information for the activated future pixel.

10. The system of claim 9, further comprising:

means for activating the at least one future pixel by applying a voltage to the at least one future pixel.

11. The system of claim 10, further comprising:

means for deactivating the activated future pixel by reversing the applied voltage to the activated future pixel.

12. The system of claim 9, further comprising:

means for activating a region of the electronic paper display based on the pen input information for the at least one current pixel; and

means for deactivating the activated region of the electronic paper display in response to, after the predetermined amount of time, an absence of receiving pen input information for the activated region.

13. The system of claim 9, wherein the pen input information is received on a touch sensor display.

14. The system of claim 9, further comprising:

means for maintaining active pixel information for each current pixel.

15. The system of claim 14, wherein the means for maintaining active pixel information includes maintaining a display list for each current pixel.

16. The system of claim 14, wherein the means for maintaining active pixel information includes maintaining a frame counter for each current pixel.

17. An apparatus for pen tracking on an electronic paper display that updates at a predetermined display update rate, comprising:

one or more processors;

an input sensor module for receiving pen input information for at least one current pixel of the electronic paper display; and

a line drawing module stored on a memory and executable by the one or more processors, the line drawing module coupled to the input sensor module and for determining the at least one current pixel to activate based on the pen input information for the at least one current pixel, predicting a direction of the pen input to determine at least one future pixel of the electronic paper display to activate based on the pen input information for the at least one current pixel and for activating the at least one current pixel of the electronic paper display independent of the display update rate of the electronic paper display;

a third module stored on the memory and executable by the one or more processors, the third module coupled to the line drawing module for activating the at least one future pixel based on the pen input information for the at least one current pixel; and

a fourth module stored on the memory and executable by the one or more processors, the fourth module coupled to the line drawing module for deactivating the activated future pixel after a predetermined amount of time in response to an absence of receiving pen input information for the activated future pixel.

18. The apparatus of claim 17, wherein the third module activates the at least one future pixel by applying a voltage to the at least one future pixel.

19. The apparatus of claim 18, wherein the fourth module deactivates the activated future pixel by reversing the applied voltage to the activated future pixel.

20. The apparatus of claim 17, wherein the third module further activates a region of the electronic paper display based on the pen input information for the at least one current pixel and the fourth module further deactivates the activated region of the electronic paper display in response to, after the predetermined amount of time, an absence of receiving pen input information for the activated region.

21. The apparatus of claim 17, wherein the pen input information is received on a touch sensor display.

22. The apparatus of claim 17, further comprising:

an active pixel buffer for maintaining active pixel information for each current pixel.

23. The apparatus of claim 22, wherein the active pixel buffer for maintaining active pixel information includes maintaining a display list for each current pixel.

24. The apparatus of claim 22, wherein the active pixel buffer for maintaining active pixel information includes maintaining a frame counter for each current pixel.