CAPACITIVE SIDE POSITION EXTRAPOLATION

• US 20170285794A1
• Filed: 03/31/2016
• Published: 10/05/2017
• Est. Priority Date: 03/31/2016
• Status: Active Grant

• Current Assignee: Synaptics Incorporated
• Original Assignee: Synaptics Incorporated
• Inventors: Tanemura, Tetsuo, Shepelev, Petr
• Granted Patent: US 10,078,406 B2
• Time in Patent Office: Days
• CPC Class Codes: G06F 2203/04108 Touchless 2D- 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 without distance measurement in the Z direction
• CPC Class Codes: G06F 3/041662 using alternate mutual and self-capacitive scanning
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes
• CPC Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• 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

A method for capacitive sensing includes acquiring a mutual capacitive measurement including effects of sensing signals of a sensing region, and acquiring an absolute capacitive measurement including effects of the sensing signals. The method further includes performing a comparison of the mutual capacitive measurement and the absolute capacitive measurement, and detecting a presence of an input object proximate to a side surface of an input device based on the comparison. The side surface is at least substantially orthogonal to the sensing region on the input device. The method further includes reporting the presence of the input object.

Claims

1. A processing system configured for capacitive side touch response extrapolation, the processing system comprising:

sensor circuitry with functionality to;

drive sensing signals on a plurality of sensor electrodes of a sensing region, the sensing region comprising a surface sensing region,

acquire a mutual capacitive measurement comprising effects of the sensing signals, and

acquire a first absolute capacitive measurement comprising effects of the sensing signals; and

processing circuitry with functionality to;

perform a first comparison of the mutual capacitive measurement and the first absolute capacitive measurement,

detect a presence of an input object proximate to a side surface of an input device based on the first comparison, wherein the side surface is at least substantially orthogonal to the surface sensing region on the input device, and

report the presence of the input object.

2. The processing system of claim 1, wherein the first mutual capacitive measurement is obtained using a first electrode, and the first absolute capacitive measurement is obtained using a second electrode.

3. The processing system of claim 2, wherein the first electrode is closer to the side surface than the second electrode.

4. The processing system of claim 1, wherein the first mutual capacitive measurement is obtained using the same electrode as the first absolute capacitive measurement.

5. The processing system of claim 1, wherein the first comparison is a ratio.

6. The processing system of claim 1, wherein the first comparison results in a comparison value and detecting a presence comprises determining whether the comparison value is within a range set by a first threshold and a second threshold.

7. The processing system of claim 6, wherein the first threshold and the second threshold are set by:

generating training data for the first comparison, wherein the training data comprises a plurality of comparison results each being for a predefined input object placed in a plurality of locations of the sensing region;

identifying the first threshold and the second threshold that distinguishes between locations of the plurality of locations proximate to the side surface as compared to location of the plurality of locations not proximate to the side surface.

8. The processing system of claim 1, wherein the sensor circuitry further comprises functionality to:

acquire a second absolute capacitive measurement comprising effects of the sensing signals;

wherein the processing circuitry further comprises functionality to;

perform a second comparison of the mutual capacitive measurement and the second absolute capacitive measurement,

wherein the presence is detected based on the first comparison and the second comparison both satisfying a criteria.

9. A method for capacitive sensing comprising:

acquiring a mutual capacitive measurement comprising effects of sensing signals of a sensing region comprising a surface sensing region;

acquiring a first absolute capacitive measurement comprising effects of the sensing signals;

performing a first comparison of the mutual capacitive measurement and the first absolute capacitive measurement;

detecting a presence of an input object proximate to a side surface of an input device based on the first comparison, wherein the side surface is at least substantially orthogonal to the surface sensing region on the input device; and

reporting the presence of the input object.

10. The method of claim 9, wherein the first mutual capacitive measurement is obtained using a first electrode, and the first absolute capacitive measurement is obtained using a second electrode.

11. The method of claim 10, wherein the first electrode is closer to the side surface than the second electrode.

12. The method of claim 9, wherein the first mutual capacitive measurement is obtained using the same electrode as the first absolute capacitive measurement.

13. The method of claim 9, wherein the first comparison is a ratio.

14. The method of claim 9, wherein the first comparison results in a comparison value and detecting a presence comprises determining whether the comparison value is within a range set by a first threshold and a second threshold.

15. The method of claim 14, wherein the first threshold and the second threshold are set by:

generating training data for the first comparison, wherein the training data comprises a plurality of comparison results each being for a predefined input object placed in a plurality of locations of a sensing region, the sensing region comprising a surface sensing region;

identifying the first threshold and the second threshold that distinguishes between locations of the plurality of locations proximate to the side surface as compared to location of the plurality of locations not proximate to the side surface.

16. The method of claim 9, further comprising:

acquiring a second absolute capacitive measurement comprising effects of the sensing signals;

performing a second comparison of the mutual capacitive measurement and the second absolute capacitive measurement,

wherein the presence is detected based on the first comparison and the second comparison both satisfying a criteria.

17. An input device for capacitive sensing comprising:

a plurality of sensor electrodes for receiving resulting signals from sensing signals; and

a processing system configured to;

acquire a mutual capacitive measurement using the resulting signals;

acquire a absolute capacitive measurement using the resulting signals;

perform a comparison of the mutual capacitive measurement and the absolute capacitive measurement;

detect a presence of an input object proximate to a side surface of an input device based on the comparison, wherein the side surface is at least substantially orthogonal to a surface sensing region on the input device; and

report the presence of the input object.

18. The input device of claim 17, wherein the mutual capacitive measurement is obtained using a first electrode, and the absolute capacitive measurement is obtained using a second electrode.

19. The input device of claim 18, wherein the first electrode is closer to the side surface than the second electrode.

20. The input device of claim 17, wherein the mutual capacitive measurement is obtained using the same electrode as the absolute capacitive measurement.