Using 3D touch for signal conditioning and noise reduction on a touch surface

Patent metadata

Field	Value
Publication number	US-10152173-B2
Application number	US-201615289098-A
Country	US
Kind code	B2
Filing date	Oct 7, 2016
Priority date	Aug 25, 2016
Publication date	Dec 11, 2018
Grant date	Dec 11, 2018

Abstract

The various implementations described herein include methods, devices, and systems for detecting touch inputs. In one aspect, a device includes: (1) a touch surface; (2) a plurality of sense electrodes configured to sense capacitance of a touch input; (3) one or more force electrodes configured to sense force of the touch input; and (4) a sensing module configured to: (a) determine a first capacitance; (b) determine whether the first capacitance exceeds an adaptive threshold; (c) if the first capacitance does not exceed the adaptive threshold, determine a force; (d) if the force meets one or more predefined criteria indicative of a touch input, lower the adaptive threshold; (e) determine a second capacitance; (f) determine whether the second capacitance exceeds the lowered threshold; and (g) if the second capacitance exceeds the lowered threshold, determine that the touch input is present on the touch surface.

First claim

What is claimed is:

1. A touch-sensing device, comprising:
a touch surface;
a plurality of sense electrodes coupled to the touch surface and configured to sense capacitance of a touch input;
one or more force electrodes coupled to the touch surface and configured to sense force of the touch input; and
a processing device electrically coupled to the plurality of sense electrodes and the one or more force electrodes, the processing device configured to:
determine a first capacitance of a first sense electrode;
determine whether the first capacitance exceeds an adaptive threshold set to a first value;
in accordance with a determination that the first capacitance does not exceed the adaptive threshold set to the first value, obtain from a force electrode of the one or more force electrodes a force signal associated with a position on the touch surface corresponding to the first sense electrode;
determine force applied on the touch surface based on the force signal;
in accordance with a determination that the determined force meets one or more predefined criteria indicative of a touch input:
determine a second value for the adaptive threshold based on one or more characteristics of the determined force and capacitive noise associated with the touch surface, wherein the second value is lower than the first value; and
set the adaptive threshold to the second value;

determine a second capacitance of the first sense electrode;
determine whether the second capacitance exceeds the adaptive threshold set to the second value; and
in accordance with a determination that the second capacitance exceeds the adaptive threshold set to the second value, determine that the touch input is present on the touch surface.

2. The device of claim 1 , wherein the processing device is further configured to, after determining that the touch input is present on the touch surface, determine a location of the touch input based on the second capacitance and the force.

3. The device of claim 1 , wherein the processing device is further configured to, after determining the force:
determine whether the first capacitance exceeds the adaptive threshold set to the second value; and
in accordance with a determination that the first capacitance exceeds the adaptive threshold set to the second value, determine that the touch input is present on the touch surface.

4. The device of claim 1 , wherein the processing device is further configured to, prior to determining the first capacitance, set the adaptive threshold to the first value.

5. The device of claim 1 , wherein the processing device is further configured to, in accordance with a determination that the second capacitance does not exceed the adaptive threshold set to the second value, determine that the touch input is not present on the touch surface.

6. The device of claim 1 , wherein the processing device is configured to concurrently measure the first capacitance and the force.

7. A method, comprising:
at a touch-sensing device having a touch surface, a plurality of sense electrodes, and one or more force electrodes:
determining a first capacitance of a first sense electrode;
determining whether the first capacitance exceeds an adaptive threshold set to a first value;
in accordance with a determination that the first capacitance does not exceed the adaptive threshold set to the first value, obtaining from a force electrode of the one or more force electrodes a force signal associated with a position on the touch surface corresponding to the first sense electrode;
determining force applied on the touch surface based on the force signal;
in accordance with a determination that the determined force meets one or more predefined criteria indicative of a touch input:
determining a second value for the adaptive threshold based on one or more characteristics of the determined force and capacitive noise associated with the touch surface, wherein the second value is lower than the first value; and
setting the adaptive threshold to the second value;

determining a second capacitance of the first sense electrode;
determining whether the second capacitance exceeds the adaptive threshold set to the second value; and
in accordance with a determination that the second capacitance exceeds the adaptive threshold set to the second value, determining that the touch input is present on the touch surface.

8. The method of claim 7 , further comprising, after determining that the touch input is present on the touch surface, determining a location of the touch input based on the second capacitance and the force.

9. The method of claim 7 , further comprising, after determining the force:
determining whether the first capacitance exceeds the adaptive threshold set to the second value; and
in accordance with a determination that the first capacitance exceeds the adaptive threshold set to the second value, determining that the touch input is present on the touch surface.

10. The method of claim 7 , further comprising, prior to determining the first capacitance, setting the adaptive threshold to the first value.

11. The method of claim 7 , further comprising, in accordance with a determination that the second capacitance does not exceed the adaptive threshold set to the second value, determining that the touch input is not present on the touch surface.

12. The method of claim 7 , wherein determining the first capacitance of the first sense electrode of the plurality of sense electrodes and determining the force applied on the touch surface based on the force signal comprises concurrently determining the first capacitance of the first sense electrode and determining the force applied on the touch surface.

13. A non-transitory computer-readable storage medium storing one or more programs, the one or more programs comprising instructions, which, when executed by a processing device of a touch-sensing device having a touch surface, a plurality of sense electrodes, and one or more force electrodes, cause the touch-sensing device to perform operations comprising:
determining a first capacitance of a first sense electrode;
determining whether the first capacitance exceeds an adaptive threshold set to a first value;
in accordance with a determination that the first capacitance does not exceed the adaptive threshold set to the first value, obtaining from a force electrode of the one or more force electrodes a force signal associated with a position on the touch surface corresponding to the first sense electrode;
determining force applied on the touch surface based on the force signal;
in accordance with a determination that the determined force meets one or more predefined criteria indicative of a touch input:
determining a second value for the adaptive threshold based on one or more characteristics of the determined force and capacitive noise associated with the touch surface, wherein the second value is lower than the first value; and
setting the adaptive threshold to the second value;

determining a second capacitance of the first sense electrode;
determining whether the second capacitance exceeds the adaptive threshold set to the second value; and
in accordance with a determination that the second capacitance exceeds the adaptive threshold set to the second value, determining that the touch input is present on the touch surface.

14. The non-transitory computer-readable storage medium of claim 13 , wherein the one or more programs further comprise instructions for, after determining that the touch input is present on the touch surface, determining a location of the touch input based on the second capacita

Assignees

• Parade Tech Ltd

Inventors

• Qu Ming
• Bentson Tom
• Lobrow Marcin
• Tucker Jeffrey
• Sterling Gary

Classifications

• G06F2203/04108

  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 title

• G06F2203/04106

  Multi-sensing digitiser, i.e. digitiser using at least two different sensing technologies simultaneously or alternatively, e.g. for detecting pen and finger, for saving power or for improving position detection · CPC title

• G06F3/0412

  Digitisers structurally integrated in a display · CPC title

• G06F2203/04105

  Pressure sensors for measuring the pressure or force exerted on the touch surface without providing the touch position · CPC title

• G06F2203/04104

  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 title