ELECTRONIC DEVICE AND METHOD OF DETECTING TOUCHES ON A TOUCH-SENSITIVE DISPLAY

• US 20130293484A1
• Filed: 05/04/2012
• Published: 11/07/2013
• Est. Priority Date: 05/04/2012
• Status: Active Grant

• Current Assignee: Malikie Innovations Limited (Key Patent Innovations Limited)
• Original Assignee: Blackberry Limited
• Inventors: SINGH, Amit Pal, ROBINSON, James Alexander, DOLSON, John Edward, PURDY, Michael Lorne, DIPPEL, Jeffery John Paul
• Granted Patent: US 9,367,120 B2
• Time in Patent Office: Days
• US Class Current: 345/173
• CPC Class Codes: G06F 1/3262 Power saving in digitizer or tablet
• CPC Class Codes: G06F 3/0416 Control or interface arrangements specially adapted for digitisers

Abstract

A method includes applying a first plurality of pulses to scanning electrodes during a first scan to detect touches on a touch-sensitive display, receiving an indication to scan in a reduced power condition, and when in the reduced power condition, applying a second plurality of pulses to scanning electrodes during a second scan to detect touches on the touch-sensitive display, wherein the second plurality of pulses comprises fewer pulses than the first plurality of pulses.

Claims

1. A method comprising:

applying a first plurality of pulses to scanning electrodes during a first scan to detect touches on a touch-sensitive display;

receiving an indication to scan in a reduced power condition;

when in the reduced power condition, applying a second plurality of pulses to scanning electrodes during a second scan to detect touches on the touch-sensitive display;

wherein the second plurality of pulses comprises fewer pulses than the first plurality of pulses.

2. The method according to claim 1, wherein applying the first plurality of pulses comprises applying pulses to one of the scanning electrodes during the first scan, and wherein applying a second plurality of pulses comprises applying fewer pulses to the one of the scanning electrodes during the second scan.

3. The method according to claim 1, wherein applying the first plurality of pulses comprises applying a number of pulses to each scanning electrode to which pulses are applied during the first scan, and wherein applying the second plurality comprises applying a fewer number of pulses to each scanning electrode to which pulses are applied during the second scan.

4. The method according to claim 1, comprising applying the first plurality of pulses to scanning electrodes during a third scan, in response to detecting a touch when in the reduced power condition.

5. The method according to claim 1, wherein receiving an indication comprises receiving, from a processor, a command to enter the reduced power condition.

6. The method according to claim 1, comprising filtering data received from sense electrodes during the first scan and discontinuing filtering when in the reduced power condition.

7. The method according to claim 1, wherein the first scan is performed at a first scanning rate, the second scan is performed at a second scanning rate, and a third scan is performed at a third scanning rate in response to detecting a touch on the touch-sensitive display, and wherein the third scanning rate is between the first scanning rate and the second scanning rate.

8. A computer-readable storage medium having computer-readable code stored thereon, the computer-readable code executable by at least one of a controller and a processor of the portable electronic device to perform the method of claim 1.

9. An electronic device comprising:

a touch-sensitive display comprising;

scanning electrodes;

sense electrodes; and

at least one controller coupled to the scanning electrodes and the sense electrodes and configured to;

apply a first plurality of pulses to the scanning electrodes during a first scan to detect touches on the touch-sensitive display;

receive an indication to scan in a reduced power condition;

when in the reduced power condition, apply a second plurality of pulses to scanning electrodes during a second scan to detect touches on the touch-sensitive display, wherein the second plurality of pulses comprises fewer pulses than the first plurality of pulses.

10. The electronic device according to claim 9, wherein the first plurality of pulses comprises pulses applied to one of the scanning electrodes during the first scan, and wherein the second plurality of pulses comprises fewer pulses applied to the one of the scanning electrodes during the second scan.

11. The electronic device according to claim 9, wherein the first plurality a number of pulses applied to each scanning electrode to which pulses are applied during the first scan, and wherein the second plurality comprises a fewer number of pulses applied to each scanning electrode to which pulses are applied during the second scan.

12. The electronic device according to claim 9, wherein the controller is configured to apply the first plurality of pulses to scanning electrodes during a third scan, in response to detecting a touch when in the reduced power condition.

13. The electronic device according to claim 9, wherein the controller is configured to filter data received from sense electrodes during the first scan and to discontinue filtering when in the reduced power condition.

14. A method comprising:

scanning a touch-sensitive display at a first scanning rate to detect touches on the touch-sensitive display;

scanning the touch-sensitive display at a second scanning rate that is less than the first scanning rate to detect touches in a reduced power condition;

in response to detecting a touch when scanning at the second scanning rate, scanning the touch-sensitive display at a third scanning rate;

wherein the third scanning rate is between the first scanning rate and the second scanning rate.

15. The method according to claim 14, comprising scanning at the first scanning rate when the touch moves a distance that meets a threshold.

16. The method according to claim 14, wherein the scanning rate is decreased from the first scanning rate to the second scanning rate by increasing a time between scans.

17. A computer-readable storage medium having computer-readable code stored thereon, the computer-readable code executable by at least one of a controller and a processor of the portable electronic device to perform the method of claim 14.