Coarse scan and targeted active mode scan for touch

• US 10,067,618 B2
• Filed: 09/29/2015
• Issued: 09/04/2018
• Est. Priority Date: 12/04/2014
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Verma, Shwetabh, Shahparnia, Shahrooz, Ranganathan, Sumant, Pant, Vivek
• Primary Examiner(s): Ma, Calvin C
• Application Number:
  US14/869,975
• Publication Number:
  US 20160162011A1
• Time in Patent Office: 1,071 Days
• Field of Search: 345173, 345174
• CPC Class Codes: G06F 1/3215 Monitoring of peripheral devices
• CPC Class Codes: G06F 1/3262 Power saving in digitizer or tablet
• CPC Class Codes: G06F 2203/04101 2.5D-digitiser, i.e. digitiser detecting the X/Y position of the input means, finger or stylus, also when it does not touch, but is proximate to the digitiser's interaction surface and also measures the distance of the input means within a short range in the Z direction, possibly with a separate measurement setup
• CPC Class Codes: G06F 3/04162 for exchanging data with external devices, e.g. smart pens, via the digitiser sensing hardware
• CPC Class Codes: G06F 3/041661 using detection at multiple resolutions, e.g. coarse and fine scanning; using detection within a limited area, e.g. object tracking window
• CPC Class Codes: G06F 3/0442 using active external devices, e.g. active pens, for transmitting changes in electrical potential to be received by the digitiser
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes

Abstract

Power consumption of touch sensing operations for touch sensitive devices can be reduced by implementing one or more coarse scans to coarsely detect the presence or absence of an object touching or proximate to a touch sensor panel and dynamically adjusting the operation of the touch sensitive device to perform or not perform one or more steps of a fine scan based on the results of the one or more coarse scans. In some examples, the fine scan can be scheduled, and one or more steps of the fine scan can be aborted when no touch is detected at touch sensors scanned during the one or more steps. Sense channels unused due to the aborted fine scan steps can be powered down during aborted fine scan steps.

Claims

1. An apparatus comprising:

sense channels configured to be coupled to one or more electrodes of a pixelated touch sensor panel; and

processing circuitry capable of;

scheduling one or more coarse scans of the pixelated touch sensor panel and a fine scan of the pixelated touch sensor panel, wherein the scheduling occurs prior to execution of the one or more coarse scans, wherein the fine scan is a higher resolution scan than the one or more coarse scans;

executing the one or more coarse scans;

beginning execution of the fine scan after executing the one or more coarse scans;

identifying one or more first banks of a plurality of first banks of electrodes of the pixelated touch sensor panel at which no touch event is detected by execution of the one or more coarse scans;

determining one or more steps of the fine scan to abort based on at least the one or more first banks at which no touch event is detected by the execution of the one or more coarse scans; and

aborting the determined one or more steps of the fine scan.

2. The apparatus of claim 1, wherein one or more of the sense channels unused during an aborted fine scan step are powered down.

3. The apparatus of claim 1, wherein the one or more coarse scans includes a self-capacitance scan, wherein each of a plurality of the sense channels is coupled to one of the plurality of first banks of electrodes of the pixelated touch sensor panel, such that the self-capacitance scan coarsely measures self-capacitance for the pixelated sensor panel in one scan step.

4. The apparatus of claim 1, wherein during each of the one or more steps of the fine scan, the sense channels are coupled to individual electrodes of one of a plurality of second banks of electrodes.

5. The apparatus of claim 4, wherein the determining one or more steps of the fine scan to abort includes determining to abort a step of the fine scan when no touch event is detected during the execution of the one or more coarse scans at electrodes of a second bank to be scanned during the step of the fine scan.

6. The apparatus of claim 5, the processing circuitry further capable of:

identifying one or more first banks of a plurality of first banks of electrodes of the pixelated touch sensor panel at which a touch event is detected by the execution of the one or more coarse scans; and

identifying one or more electrodes proximate to and outside the one or more first banks at which the event is detected as having detected the touch event.

7. The apparatus of claim 5, the processing circuitry further capable of:

identifying one or more first banks of a plurality of first banks of electrodes of the pixelated touch sensor panel at which a touch event is detected by the execution of the one or more coarse scans; and

identifying one or more electrodes linked to the one or more first banks at which the event is detected as having detected the touch event.

8. The apparatus of claim 1, wherein determining the one or more steps of the fine scan to abort includes determining to not abort a step of the fine scan irrespective of the one or more coarse scans based on a state of the device.

9. The apparatus of claim 1, the processing circuitry further capable of:

replacing an aborted step of the fine scan with a duplicate of a non-aborted scan step of the fine scan.

10. The apparatus of claim 1, the processing circuitry further capable of:

replacing an aborted step of the fine scan with a non-aborted scan step of the fine scan.

11. A method for reducing power consumption of touch scanning operations for a device including a pixelated touch sensor panel, comprising:

scheduling one or more coarse scans of the pixelated touch sensor panel and a fine scan of the pixelated touch sensor panel, wherein the scheduling occurs prior to execution of the one or more coarse scans, wherein the fine scan is a higher resolution scan than the one or more coarse scans;

executing the one or more coarse scans;

beginning execution of the fine scan after executing the one or more coarse scans;

identifying one or more first banks of a plurality of first banks of electrodes of the pixelated touch sensor panel at which no touch event is detected by execution of the one or more coarse scans;

determining one or more steps of the fine scan to abort based on at least the one or more first banks at which no touch event is detected by the execution of the one or more coarse scans; and

aborting the determined one or more steps of the fine scan.

12. The method of claim 11, further comprising:

powering down one or more sense channels unused during an aborted fine scan step.

13. The method of claim 11, wherein the one or more coarse scans includes a self-capacitance scan that measures a self-capacitance for each of the plurality of first banks of electrodes such that the pixelated sensor panel is coarsely scanned in one scan step.

14. The method of claim 11, wherein each step of the fine scan scans electrodes of one of a plurality of second banks of electrodes.

15. The method of claim 14, wherein determining the one or more steps of the fine scan to abort includes determining to abort a step of the fine scan when no touch event is detected during the execution of the one or more coarse scans at electrodes of a second bank to be scanned during the step of the fine scan.

16. The method of claim 15, further comprising:

identifying one or more first banks of a plurality of first banks of electrodes of the pixelated touch sensor panel at which a touch event is detected by the execution of the one or more coarse scans; and

identifying one or more electrodes proximate to and outside the one or more first banks at which the event is detected as having detected the touch event.

17. The method of claim 15, further comprising:

identifying one or more first banks of a plurality of first banks of electrodes of the pixelated touch sensor panel at which a touch event is detected by the execution of the one or more coarse scans; and

identifying one or more electrodes linked to the one or more first banks at which the event is detected as having detected the touch event.

18. The method of claim 11, further comprising:

replacing an aborted step of the fine scan with a duplicate of a non-aborted scan step of the fine scan.

19. The method of claim 11, further comprising:

replacing an aborted step of the fine scan with a non-aborted scan step of the fine scan.

20. The method of claim 11, wherein determining the one or more steps of the fine scan to abort includes determining to not abort a step of the fine scan irrespective of the one or more coarse scans based on a state of the device.

21. A non-transitory computer readable storage medium, the computer readable medium containing instructions that, when executed by a processor, can perform a method, the method comprising:

scheduling one or more coarse scans of the pixelated touch sensor panel and a fine scan of the pixelated touch sensor panel, wherein the scheduling occurs prior to execution of the one or more coarse scans, wherein the fine scan is a higher resolution scan than the one or more coarse scans;

executing the one or more coarse scans;

beginning execution of the fine scan after executing the one or more coarse scans;

identifying one or more first banks of a plurality of first banks of electrodes of the pixelated touch sensor panel at which no touch event is detected by execution of the one or more coarse scans;

determining one or more steps of the fine scan to abort based on at least the one or more first banks at which no touch event is detected by the execution of the one or more coarse scans; and

aborting the determined one or more steps of the fine scan.

22. The non-transitory computer readable storage medium of claim 21, further comprising:

powering down one or more sense channels unused during an aborted fine scan step.

23. The non-transitory computer readable storage medium of claim 21, wherein each step of the fine scan scans electrodes of one of a plurality of second banks of electrodes;

and wherein determining one or more steps of the fine scan to abort includes determining to abort a step of the fine scan when no touch event is detected during the execution of the one or more coarse scans at electrodes of a second bank to be scanned during the step of the fine scan.

24. The non-transitory computer readable storage medium of claim 23, further comprising:

identifying one or more first banks of a plurality of first banks of electrodes of the pixelated touch sensor panel at which a touch event is detected by the execution of the one or more coarse scans; and

identifying one or more electrodes proximate to and outside the one or more first banks at which the event is detected as having detected the touch event.

25. The non-transitory computer readable storage medium of claim 21, further comprising:

replacing an aborted step of the fine scan with a duplicate of a non-aborted scan step of the fine scan.