Combined capacitive sensing

Patent metadata

Field	Value
Publication number	US-9753570-B2
Application number	US-201414527688-A
Country	US
Kind code	B2
Filing date	Oct 29, 2014
Priority date	Mar 14, 2014
Publication date	Sep 5, 2017
Grant date	Sep 5, 2017

Abstract

A processing system comprises a sensor module and a determination module. The sensor module comprises sensing circuitry coupled to sensor electrodes of a sensor electrode pattern. The sensor module is configured to: drive a modulated signal onto a first sensor electrode of the sensor electrode pattern; receive first resulting signals from the first sensor electrode; and receive second resulting signals from a second sensor electrode of the sensor electrode pattern. The second resulting signals comprise effects corresponding to the modulated signal, and the first resulting signals and the second resulting signals are simultaneously received. The determination module configured to determine a change in capacitive coupling between an input object and the first sensor electrode based on the first resulting signals and a change in capacitive coupling between the first and second sensor electrodes based on the second resulting signals.

First claim

What is claimed is:

1. A processing system comprising:
a sensor module comprising sensing circuitry coupled to sensor electrodes of a sensor electrode pattern, said sensor module configured to:
drive a modulated signal onto a first sensor electrode of said sensor electrode pattern;
drive a second modulated signal on a second sensor electrode of said sensor electrode pattern, wherein said second modulated signal has a phase opposite that of said modulated signal, and wherein said modulated signal and said second modulated signal are driven concurrently;
receive first resulting signals from said first sensor electrode; and
receive second resulting signals from said second sensor electrode, said second resulting signals comprising effects corresponding to said modulated signal, and wherein said first resulting signals and said second resulting signals are simultaneously received; and

a determination module configured to determine a capacitive coupling between an input object and said first sensor electrode based on said first resulting signals and a change in capacitive coupling between said first and second sensor electrodes based on said second resulting signals.

2. The processing system of claim 1 , wherein said sensor module is further configured to drive a guarding signal on a third sensor electrode of said sensor electrode pattern, said third sensor electrode proximate said first sensor electrode, wherein said guarding signal is in-phase with said modulated signal.

3. The processing system of claim 1 , wherein said second resulting signal comprises effects corresponding to said modulated signal and said second modulated signal.

4. The processing system of claim 1 , wherein said sensor module is further configured to receive third resulting signals with a third sensor electrode of said sensor electrode pattern, wherein said third resulting signals are received simultaneously with said first resulting signals and said second resulting signals.

5. The processing system of claim 4 , wherein said second sensor electrode is one of a first plurality of sensor electrodes disposed along a first axis of said sensor electrode pattern; and
wherein said third sensor electrode is one of a second plurality of sensor electrodes disposed along a second axis of said sensor electrode pattern that is substantially orthogonal to said first axis.

6. The processing system of claim 5 , wherein:
said sensor module is further configured to:
drive a third modulated signal onto said third sensor electrode;
receive fourth resulting signals with said third sensor electrode;
receive fifth resulting signals with said first sensor electrode and sixth resulting signals with said second sensor electrode, the fifth resulting signals and the sixth resulting signals comprises effects corresponding to said third modulated signal;

and
based on the first, second, third, fourth, fifth and sixth resulting signals, said determination module is further configured to determine a first capacitive image along said first axis, a second capacitive image along said second axis, an absolute capacitive profile along the first axis, an absolute capacitive profile along the second axis, a transcapacitive profile along the first axis, and a transcapacitive profile along the second axis.

7. The processing system of claim 6 , wherein said first sensor electrode is one of said first plurality of sensor electrodes.

8. The processing system of claim 6 , wherein said first sensor electrode is one of said second plurality of sensor electrodes.

9. A capacitive sensing input device comprising:
a plurality of sensor electrodes disposed in a sensor electrode pattern; and
a processing system configured to operate said sensor electrodes to perform simultaneous absolute capacitive sensing and transcapacitive sensing, wherein said processing system is configured to:
drive a modulated signal onto a first sensor electrode of said sensor electrode pattern;
drive a second modulated signal on a second sensor electrode of said sensor electrode pattern, wherein said second modulated signal has a phase opposite that of said modulated signal, and wherein said modulated signal and said second modulated signal are driven concurrently;
receive first resulting signals from said first sensor electrode;
receive second resulting signals from said second sensor electrode, said second resulting signals comprising effects corresponding to said modulated signal, and wherein said first resulting signals and said second resulting signals are simultaneously received; and
determine a capacitive coupling between an input object and said first sensor electrode based on said first resulting signals and a change in capacitive coupling between said first and second sensor electrodes based on said second resulting signals.

10. The capacitive sensing input device of claim 9 , wherein said processing system is further configured to receive third resulting signals with a third sensor electrode of said sensor electrode pattern, wherein said third resulting signals are received simultaneously with said first resulting signals and said second resulting signals.

11. The capacitive sensing input device of claim 10 , wherein said second sensor electrode is one of a first plurality of sensor electrodes disposed along a first axis of said sensor electrode pattern; and
wherein said third sensor electrode is one of a second plurality of sensor electrodes disposed along a second axis of said sensor electrode pattern that is substantially orthogonal to said first axis.

12. The capacitive sensing input device of claim 11 , wherein said processing system is further configured to:
drive a third modulated signal onto said third sensor electrode;
receive fourth resulting signals with said third sensor electrode;
receive fifth resulting signals with said first sensor electrode and sixth resulting signals with said second sensor electrode, the fifth resulting signals and the sixth resulting signals comprises effects corresponding to said third modulated signal; and
based on the first, second, third, fourth, fifth and sixth resulting signals, determine a first capacitive image along said first axis, a second capacitive image along said second axis, an absolute capacitive profile along the first axis, an absolute capacitive profile along the second axis, a transcapacitive profile along the first axis, and a transcapacitive profile along the second axis.

13. The capacitive sensing input device of claim 11 , wherein said first sensor electrode is one of said first plurality of sensor electrodes.

14. The capacitive sensing input device of claim 11 , wherein said first sensor electrode is one of said second plurality of sensor electrodes.

15. The capacitive sensing input device of claim 11 , wherein said sensor electrode pattern comprises a single-layer sensor electrode pattern, and wherein said first plurality of sensor electrodes and said second plurality of sensor electrodes are disposed entirely in a common layer with one another.

16. The capacitive sensing input device of claim 11 , wherein said first plurality of sensor electrodes and said second plurality of sensor electrodes are disposed in different layers of said sensor electrode pattern.

17. The capacitive sensing input device of claim 9 , wherein said second resulting signal comprises effects corresponding to said modulated signal and said second modulated signal.

18. A method of capacitive sensing, said method comprising:
driving a modulated signal onto a first sensor electrode of a

Assignees

• Synaptics Inc

Inventors

• Reynolds Joseph Kurth
• Dattalo Tracy Scott
• Hoch David

Classifications

• G06F3/0416 Primary

  Control or interface arrangements specially adapted for digitisers · CPC title

• G06F3/044

  by capacitive means · CPC title

• G06F2203/04107

  Shielding in digitiser, i.e. guard or shielding arrangements, mostly for capacitive touchscreens, e.g. driven shields, driven grounds · CPC title

• G06F3/041662 Primary

  using alternate mutual and self-capacitive scanning · CPC title

• G06F3/0446

  using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes · CPC title