COARSE SCAN AND TARGETED ACTIVE MODE SCAN FOR TOUCH

• US 20160162102A1
• Filed: 09/29/2015
• Published: 06/09/2016
• Est. Priority Date: 12/04/2014
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Shahparnia, Shahrooz, Mullens, Christopher Tenzin, GRUNTHANER, Martin Paul, Geboff, Adam
• Granted Patent: US 10,061,450 B2
• Time in Patent Office: Days
• 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 a coarse scan (e.g., banked common mode scan) to coarsely detect the presence or absence of an object touching or proximate to a touch sensor panel and the results of the coarse scan can be used to dynamically adjust the operation of the touch sensitive device to perform or not perform a fine scan (e.g., targeted active mode scan). In some examples, the results of the coarse scan can be used to program a touch controller for the next touch sensing frame to idle when no touch event is detected or to perform a fine scan when one or more touch events are detected. In some examples, the results of the coarse scan can be used to abort a scheduled fine scan during the current touch sensing frame when no touch event is detected.

Claims

1. An apparatus comprising:

a touch sensor panel; and

processing circuitry capable of;

scheduling a coarse scan and a fine scan to be executed during a scan frame;

executing the coarse scan; and

aborting at least a portion of the fine scan when no touch event is detected during execution of the coarse scan.

2. The apparatus of claim 1, wherein the touch sensor panel comprises drive lines and sense lines, and executing the coarse scan comprises:

stimulating a bank comprising a plurality of the drive lines with a common mode stimulation signal;

receiving sense signals at one or more of the sense lines, the sense signals generated in response to the common mode stimulation signal; and

generating at least one touch value for the bank.

3. The apparatus of claim 1, wherein the touch sensor panel comprises drive lines and sense lines, and executing the fine scan comprises:

stimulating, in one or more steps, the drive lines with stimulation signals;

receiving sense signals at the sense lines, the sense signals generated in response to the stimulation signals applied to the drive lines; and

generating a touch value for a plurality of touch sensing nodes of the touch sensor panel, each of the plurality of touch sensing nodes measuring a mutual capacitance between a drive line and a sense line.

4. The apparatus of claim 1, wherein the touch sensor panel comprises drive lines and sense lines, and executing the fine scan comprises:

stimulating, in one or more steps, the drive lines of one or more banks, but fewer than all banks, with stimulation signals, each bank comprising a plurality of the drive lines, at least one of the one or more banks having detected a touch event during the coarse scan;

receiving sense signals at the sense lines, the sense signals generated in response to the stimulation signals applied to the drive lines of the one or more banks; and

generating a touch value for a plurality of touch sensing nodes corresponding to the one or more banks, each touch sensing node measuring a mutual capacitance between a drive line and a sense line.

5. The apparatus of claim 1, wherein the processing circuitry is further capable of generating an abort command, the abort command preventing or terminating execution of the fine scan.

6. The apparatus of claim 1, wherein the processing circuitry is further capable of generating a one or more abort commands, the one or more abort commands preventing or terminating execution of one or more portions of the fine scan.

7. The apparatus of claim 1, wherein the processing circuitry is further capable of discarding scan results from an aborted fine scan.

8. An apparatus comprising:

a touch sensor panel; and

processing circuitry capable of;

performing, during a first touch sensing frame, a first coarse scan;

determining an operation for a second touch sensing frame based on a result of the first coarse scan;

performing, during the second touch sensing frame, a second coarse scan; and

performing, during the second touch sensing frame, the determined operation.

9. The apparatus of claim 8, wherein the processing circuitry comprises a touch controller capable of performing scanning operations, and a portion of the processing circuitry is capable of programming the touch controller to perform the determined operation during the second touch sensing frame.

10. The apparatus of claim 8, wherein the first and second coarse scans are banked common mode scans.

11. The apparatus of claim 8, wherein determining the operation for the second touch sensing frame based on the result of the first coarse scan comprises determining an idle operation when the results of the first coarse scan indicate no touch event was detected.

12. The apparatus of claim 8, wherein determining the operation for the second touch sensing frame based on the result of the first coarse scan comprises determining a full panel scan operation when the results of the first coarse scan indicate one or more touch events detected at at least a threshold number of banks of the touch sensor panel.

13. The apparatus of claim 8, wherein determining the operation for the second touch sensing frame based on the result of the first coarse scan comprises determining a partial panel scan operation when the results of the first coarse scan indicate touch events detected at fewer than a threshold number of banks of the touch sensor panel.

14. A method for reducing power consumption of touch scanning operations, comprising:

scheduling a coarse scan and a fine scan to be executed during a scan frame;

executing the coarse scan; and

aborting at least a portion of the fine scan when no touch event is detected during execution of the coarse scan.

15. The method of claim 14, wherein the coarse scan is a banked common mode scan, wherein drive lines of a touch sensor panel are divided between a plurality of banks, and banks are stimulated with a common mode stimulation signal.

16. The method of claim 14, wherein the fine scan is a full panel scan.

17. The method of claim 14, wherein scan results from the fine scan are discarded or ignored.

18. A method for dynamically adjusting operation of a device comprising a touch sensor panel and processing circuitry for an upcoming scan frame, the method comprising:

performing, during a first touch sensing frame, a first coarse scan;

determining an operation for a second touch sensing frame based on a result of the first coarse scan;

performing, during the second touch sensing frame, a second coarse scan; and

performing, during the second touch sensing frame, the determined operation.

19. The method of claim 18, wherein the processing circuitry comprises a touch controller capable of performing scanning operations, and a portion of the processing circuitry is capable of programming the touch controller to perform the determined operation during the second touch sensing frame.

20. The method of claim 18, wherein the first and second coarse scans are banked common mode scans.

21. The method of claim 18, wherein determining the operation for the second touch sensing frame based on the result of the first coarse scan comprises determining an idle operation when the results of the first coarse scan indicate no touch event was detected

22. The method of claim 18, wherein determining the operation for the second touch sensing frame based on the result of the first coarse scan comprises determining a full panel scan operation when the results of the first coarse scan indicate one or more touch events detected at at least a threshold number of banks of the touch sensor panel.

23. The method of claim 18, wherein determining the operation for the second touch sensing frame based on the result of the first coarse scan comprises determining a partial panel scan operation when the results of the first coarse scan indicate touch events detected at fewer than a threshold number of banks of the touch sensor panel.

24. 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 a coarse scan and a fine scan to be executed during a scan frame;

executing the coarse scan; and

aborting at least a portion of the fine scan when no touch event is detected during execution of the coarse scan.

25. 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:

performing, during a first touch sensing frame, a first coarse scan;

determining an operation for a second touch sensing frame based on a result of the first coarse scan;

performing, during the second touch sensing frame, a second coarse scan; and

performing, during the second touch sensing frame, the determined operation.