UNGROUNDED USER SIGNAL COMPENSATION FOR PIXELATED SELF-CAPACITANCE TOUCH SENSOR PANEL

• US 20170285804A1
• Filed: 09/22/2014
• Published: 10/05/2017
• Est. Priority Date: 09/22/2014
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: LI, Yingxuan, YOUSEFPOR, Marduke, YAO, Weijun
• Granted Patent: US 10,705,658 B2
• Time in Patent Office: Days
• CPC Class Codes: G06F 2203/04103 Manufacturing, i.e. details related to manufacturing processes specially suited for touch sensitive devices
• CPC Class Codes: G06F 2203/04104 Multi-touch detection in digitiser, i.e. details about the simultaneous detection of a plurality of touching locations, e.g. multiple fingers or pen and finger
• CPC Class Codes: G06F 3/041662 using alternate mutual and self-capacitive scanning
• CPC Class Codes: G06F 3/0418 for error correction or compensation, e.g. based on parallax, calibration or alignment
• CPC Class Codes: G06F 3/044 by capacitive means
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes

Abstract

A touch controller is disclosed. The touch controller can include sense circuitry configured to sense, during a self-capacitance portion of a touch frame, first one or more self-capacitances associated with a first plurality of touch pixels on a touch sensor panel, and sense, during a mutual capacitance portion of the touch frame, first one or more mutual capacitances associated with the first plurality of touch pixels. A touch processor can be configured to, based on the first one or more self-capacitances and the first one or more mutual capacitances, sense a single touch event associated with the touch frame.

Claims

1. A touch controller comprising:

sense circuitry configured to;

sense, during a self-capacitance portion of a touch frame, first one or more self-capacitances associated with a first plurality of touch pixels on a touch sensor panel, and

sense, during a mutual capacitance portion of the touch frame, first one or more mutual capacitances associated with the first plurality of touch pixels; and

a touch processor configured to, based on the first one or more self-capacitances and the first one or more mutual capacitances, sense a single touch event associated with the touch frame.

2. The touch controller of claim 1, wherein:

the first one or more self-capacitances comprise a first self-capacitance associated with a first touch pixel, and

the first one or more mutual capacitances comprise a first mutual-capacitance associated with the first touch pixel and a second touch pixel.

3. The touch controller of claim 2, wherein the touch processor is further configured to adjust the first self-capacitance based on the first mutual capacitance.

4. The touch controller of claim 3, wherein adjusting the first self-capacitance comprises scaling the first self-capacitance by a first scaling factor based on the first self-capacitance and the first mutual capacitance.

5. The touch controller of claim 3, wherein:

the first one or more self-capacitances further comprise a second self-capacitance associated with the second touch pixel, a third self-capacitance associated with a third touch pixel, and a fourth self-capacitance associated with a fourth touch pixel on the touch sensor panel,

the first one or more mutual capacitances further comprise a second mutual capacitance associated with the third touch pixel and the fourth touch pixel, and

adjusting the first self-capacitance comprises adjusting the first self-capacitance based on the first, second, third and fourth self-capacitances, and the first and second mutual capacitances.

6. The touch controller of claim 5, wherein the touch processor is further configured to:

adjust the second self-capacitance based on the first, second, third and fourth self-capacitances, and the first and second mutual capacitances.

7. The touch controller of claim 6, wherein:

adjusting the first self-capacitance comprises scaling the first self-capacitance by a first scaling factor, and

adjusting the second self-capacitance comprises scaling the second self-capacitance by a second scaling factor, different from the first scaling factor.

8. The touch controller of claim 6, wherein:

adjusting the first self-capacitance comprises scaling the first self-capacitance by an average scaling factor, and

adjusting the second self-capacitance comprises scaling the second self-capacitance by the average scaling factor.

9. The touch controller of claim 1, wherein:

the sense circuitry is further configured to;

sense second one or more self-capacitances associated with a second plurality of touch pixels on the touch sensor panel, different from the first plurality of touch pixels, and

sense second one or more mutual capacitances associated with the second plurality of touch pixels, and

the touch processor is further configured to, based on the second one or more self-capacitances and the second one or more mutual capacitances, sense the single touch event.

10. The touch controller of claim 9, wherein the sense circuitry is configured to concurrently sense the first one or more self-capacitances and the second one or more self-capacitances.

11. The touch controller of claim 9, wherein the sense circuitry is configured to sequentially sense the first one or more self-capacitances and the second one or more self-capacitances.

12. A method comprising:

sensing, during a self-capacitance portion of a touch frame, first one or more self-capacitances associated with a first plurality of touch pixels on a touch sensor panel;

sensing, during a mutual capacitance portion of the touch frame, first one or more mutual capacitances associated with the first plurality of touch pixels; and

based on the first one or more self-capacitances and the first one or more mutual capacitances, sensing a single touch event associated with the touch frame.

13. The method of claim 12, wherein:

the first one or more self-capacitances comprise a first self-capacitance associated with a first touch pixel, and

the first one or more mutual capacitances comprise a first mutual-capacitance associated with the first touch pixel and a second touch pixel.

14. The method of claim 13, further comprising adjusting the first self-capacitance based on the first mutual capacitance.

15. The method of claim 14, wherein adjusting the first self-capacitance comprises scaling the first self-capacitance by a first scaling factor based on the first self-capacitance and the first mutual capacitance.

16. The method of claim 14, wherein:

the first one or more self-capacitances further comprise a second self-capacitance associated with the second touch pixel, a third self-capacitance associated with a third touch pixel, and a fourth self-capacitance associated with a fourth touch pixel on the touch sensor panel,

the first one or more mutual capacitances further comprise a second mutual capacitance associated with the third touch pixel and the fourth touch pixel, and

adjusting the first self-capacitance comprises adjusting the first self-capacitance based on the first, second, third and fourth self-capacitances, and the first and second mutual capacitances.

17. The method of claim 16, further comprising adjusting the second self-capacitance based on the first, second, third and fourth self-capacitances, and the first and second mutual capacitances.

18. The method of claim 17, wherein:

adjusting the first self-capacitance comprises scaling the first self-capacitance by a first scaling factor, and

adjusting the second self-capacitance comprises scaling the second self-capacitance by a second scaling factor, different from the first scaling factor.

19. The method of claim 17, wherein:

adjusting the first self-capacitance comprises scaling the first self-capacitance by an average scaling factor, and

adjusting the second self-capacitance comprises scaling the second self-capacitance by the average scaling factor.

20. The method of claim 12, further comprising:

sensing second one or more self-capacitances associated with a second plurality of touch pixels on the touch sensor panel, different from the first plurality of touch pixels, and

sensing second one or more mutual capacitances associated with the second plurality of touch pixels, and

based on the second one or more self-capacitances and the second one or more mutual capacitances, sensing the single touch event.

21. The method of claim 20, wherein sensing the first one or more self-capacitances is concurrent with sensing the second one or more self-capacitances.

22. The method of claim 20, wherein sensing the second one or more self-capacitances is sequential to sensing the first one or more self-capacitances.

23. A touch sensor panel comprising:

a plurality of touch pixels, the plurality of touch pixels including a first touch pixel, a second touch pixel, a third touch pixel, and a fourth touch pixel; and

sense circuitry configured to;

during a first time period, drive the first touch pixel, and ground the fourth touch pixel;

during a second time period, drive the second touch pixel, and ground the third touch pixel;

during a third time period, drive the third touch pixel, and ground the second touch pixel;

during a fourth time period, drive the fourth touch pixel, and ground the first touch pixel;

during a fifth time period, drive the first touch pixel, and ground the second and third touch pixels; and

during a sixth time period, drive the second touch pixel, and ground the first and fourth touch pixels.

24. A touch sensor panel comprising:

a plurality of touch pixels, the plurality of touch pixels including a first touch pixel, a second touch pixel, a third touch pixel, and a fourth touch pixel; and

sense circuitry configured to;

during a first time period, sense a first self-capacitance of the first touch pixel;

during a second time period, sense a second self-capacitance of the second touch pixel;

during a third time period, sense a third self-capacitance of the third touch pixel;

during a fourth time period, sense a fourth self-capacitance of the fourth touch pixel;

during a fifth time period, sense a first mutual capacitance of the first touch pixel and the fourth touch pixel; and

during a sixth time period, sense a second mutual capacitance of the second touch pixel and the third touch pixel.