Interference sensing within a display device with an integrated sensing device

• US 8,907,921 B2
• Filed: 08/29/2012
• Issued: 12/09/2014
• Est. Priority Date: 08/30/2011
• Status: Active Grant

• Current Assignee: Synaptics Incorporated
• Original Assignee: Synaptics Incorporated
• Inventors: Reynolds, Joseph Kurth
• Primary Examiner(s): Eisen, Alexander
• Assistant Examiner(s): Sarma, Abhishek
• Application Number:
  US13/598,436
• Publication Number:
  US 20130050144A1
• Time in Patent Office: 832 Days
• Field of Search: 345173-174, 178/18.01
• US Class Current: 345/174
• 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 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer

Abstract

Embodiments of the present invention generally provide a method and system for sensing interference in a display device having integrated input sensing. In various embodiments of the invention, input sensing performed on one or more rows of common electrodes may be operated for interference sensing, and, during the blanking period, some or all of the common electrodes may be operated for interference sensing. Interference measurements acquired during blanking periods may be used to increase the accuracy with which input sensing is performed, for example, by establishing one or more baseline interference values and/or determining that one or more common electrodes should be driven at a different frequency. In some embodiments, all of the common electrodes may be operated for interference sensing during a blanking period, while in other embodiments a portion of the common electrodes (e.g., one-third, one-half, etc.) may be operated for interference sensing during a blanking period.

Claims

1. A processing system for a display device with an integrated capacitive sensing device comprising:

a driver module configured to be communicatively coupled to a plurality of common electrodes configured for capacitive sensing and display updating, the plurality of common electrodes comprising a first set of common electrodes and a second set of common electrodes, the first set of the common electrodes including at least one common electrode included in the second set of the common electrodes and at least one common electrode not included in the second set of the common electrodes, the driver module configured for;

driving the plurality of common electrodes for display updating during a first display frame;

driving the first set of common electrodes for capacitive sensing during a first portion of the first display frame, wherein at least one common electrode included in the second set of the common electrodes is not driven for capacitive sensing during the first display frame; and

operating the plurality of common electrodes in a substantially non-modulating manner for interference sensing during a second portion of the first display frame;

a receiver module configured to be communicatively coupled to a plurality of receiver electrodes, the receiver module configured for;

receiving first resulting signals during the first portion of the first display frame; and

receiving second resulting signals during the second portion of the first display frame; and

a determination module configured for determining at least portion of a first capacitive frame based on the first resulting signals and an interference measurement corresponding to the first capacitive frame based on the second resulting signals.

2. The processing system of claim 1, further comprising the driver module configured for:

driving the plurality of common electrodes for display updating during a second display frame

driving the second set of common electrodes for capacitive sensing during a first portion of the second display frame; and

operating the plurality of common electrodes in a substantially non-modulating manner for interference sensing during a second portion of the second display frame;

the receiver module configured for;

receiving third resulting signals during the first portion of the second display frame; and

receiving fourth resulting signals during the second portion of the second display frame with the plurality of receiver electrodes; and

the determination module configured for determining at least portion of a second capacitive frame based on the third resulting signals and an interference measurement corresponding to the second capacitive frame based on the fourth resulting signals.

3. The processing system of claim 1, further comprising the driver module configured for:

driving the plurality of common electrodes for display updating during a second display frame

driving a third set of common electrodes for capacitive sensing during a first portion of the second display frame, the third set of the common electrodes including at least one common electrode not included in the first set of the common electrodes; and

the receiver module configured for;

receiving third resulting signals during the first portion of the second display frame with the plurality of receiver electrodes; and

the determination module is further configured for determining at least second portion of a first capacitive frame based on the third resulting signals.

4. The processing system of claim 1, further comprising the driver module configured for:

driving a third set of common electrodes for capacitive sensing during a third portion of the first display frame, the third set of the common electrodes including at least one common electrode not included in the first set of the common electrodes; and

the receiver module further configured for;

receiving third resulting signals during the third portion of the first display frame with the plurality of receiver electrodes; and

the determination module is further configured for determining at least a second portion of a first capacitive frame based on the third resulting signals.

5. The processing system of claim 1, wherein the driver module is further configured to drive the first and second set of common electrodes for capacitive sensing and operate the plurality of common electrodes in a non-modulating manner during the first display frame during a non-display update period of the display device.

6. The processing system of claim 1, wherein operating the plurality of common electrodes in a non-modulating manner for interference sensing during a second portion of the first display frame comprises at least one of driving the plurality of common electrodes with a substantially constant voltage and electrically floating the plurality of common electrodes.

7. The processing system of claim 6, wherein the substantially constant voltage comprises a system reference voltage.

8. The processing system of claim 1, wherein driving the first set of common electrodes for capacitive sensing during a first portion of the first display frame comprises driving the first set of common electrodes with a first transmitter signal having a first frequency and wherein the processing system is configured to shift from driving the first set of common electrodes with the first transmitter signal having the first frequency to driving the first set of common electrodes with a second transmitter signal having a second frequency based on the interference measurement, wherein the first frequency is different than the second frequency.

9. The processing system of claim 1, wherein the processing system is configured to determine a baseline interference value based on the second resulting signals.

10. A processing system with an integrated capacitive sensing device comprising:

a plurality of common electrodes configured for capacitive sensing and display updating, the plurality of common electrodes comprising a first set of common electrodes and a second set of common electrodes, the first set of the common electrodes including at least one common electrode included in the second set of the common electrodes and at least one common electrode not included in the second set of the common electrodes;

a driver module configured to be communicatively coupled to the plurality of common electrodes and configured to;

drive the plurality of common electrodes for display updating during a first display frame and during a second display frame;

drive the first set of common electrodes for capacitive sensing during a first portion of the first display frame, wherein at least one common electrode included in the second set of the common electrodes is not driven for capacitive sensing during the first display frame;

operate the plurality of common electrodes in a substantially non-modulating manner for interference sensing during a second portion of the first display frame;

drive the second set of common electrodes for capacitive sensing during a first portion of the second display frame; and

operate the plurality of common electrodes in a substantially non-modulating manner for interference sensing during a second portion of the second display frame;

a plurality of receiver electrodes;

a receiver module configured to be communicatively coupled to a plurality of receiver electrodes and configured to;

receive first resulting signals during the first portion of the first display frame, second resulting signals during the second portion of the first display frame, third resulting signals during the first portion of the second display frame, and fourth resulting signals during the second portion of the second display frame with the plurality of receiver electrodes; and

a determination module configured to determine at least portion of a first capacitive frame based on the first resulting signals and an interference measurement corresponding to the first capacitive frame based on the second resulting signals.

11. The display device of claim 10, wherein the determination module is further configured to determine at least portion of a second capacitive frame based on the third resulting signals and an interference measurement corresponding to the second capacitive frame based on the fourth resulting signals.

12. The display device of claim 10, wherein the driver module is further configured to drive a third set of the common electrodes for capacitive sensing during a third portion of the first display frame, the third set of the common electrodes including at least one common electrode not included in the first set of the common electrodes, the receiver module is further configured to receive fifth resulting signals with the receiver electrodes during the third portion of the first display frame and the determination module is further configured to determine the first capacitive frame based on at least a portion of the fifth resulting signals.

13. The display device of claim 10, wherein the driver module is further configured to drive a third set of the common electrodes for capacitive sensing during a third portion of the second display frame, the third set of the common electrodes including at least one common electrode not included in the first set of the common electrodes, the receiver module is further configured to receive fifth resulting signals with the receiver electrodes during the third portion of the second display frame and the determination module is further configured to determine the first capacitive frame based on at least a portion of the fifth resulting signals.

14. The display device of claim 10, wherein operating the plurality of common electrodes in a substantially non-modulating manner for interference sensing during the second portion of the first display frame and during the second portion of the second display frame comprises one of driving the plurality of common electrodes with a substantially constant voltage and electrically floating the plurality of common electrodes.

15. The display device of claim 10, wherein driving the first set of common electrodes for capacitive sensing during a first portion of the first display frame comprises driving the first set of common electrodes with a first transmitter signal having a first frequency and wherein the processing system is configured to shift from driving the first set of common electrodes with the first transmitter signal having the first frequency to driving the first set of common electrodes with a second transmitter signal having a second frequency based on the interference measurement, wherein the first frequency is different than the second frequency.

16. A method of capacitive sensing in a display device having a plurality of common electrodes configured for capacitive sensing and display updating, the plurality of common electrodes comprising a first set of common electrodes and a second set of common electrodes, the first set of the common electrodes including at least one common electrode included in the second set of the common electrodes and at least one common electrode not included in the second set of the common electrodes, the method comprising:

driving the plurality of common electrodes for display updating during a first display frame and during a second display frame;

driving the first set of common electrodes for capacitive sensing during a first portion of the first display frame, wherein at least one common electrode included in the second set of the common electrodes is not driven for capacitive sensing during the first display frame;

operating the plurality of common electrodes in a substantially non-modulating manner for interference sensing during a second portion of the first display frame;

driving the second set of common electrodes for capacitive sensing during a first portion of the second display frame;

operating the plurality of common electrodes in a substantially non-modulating manner for interference sensing during a second portion of the second display frame;

receiving first resulting signals during the first portion of the first display frame;

receiving second resulting signals during the second portion of the first display frame;

receiving third resulting signals during the first portion of the second display frame;

receiving fourth resulting signals during the second portion of the second display frame; and

determining at least portion of a first capacitive frame based on the first resulting signals and an interference measurement corresponding to the first capacitive frame based on the second resulting signals.

17. The method of claim 16, further comprising determining at least portion of a second capacitive frame based on the third resulting signals and an interference measurement corresponding to the second capacitive frame based on the fourth resulting signals.

18. The method of claim 16, further comprising:

driving a third set of the common electrodes for capacitive sensing during a third portion of the first display frame, the third set of the common electrodes including at least one common electrode not included in the first set of the common electrodes;

receiving fifth resulting signals during the third portion of the first display frame; and

determining the first capacitive frame based on at least a portion of the fifth resulting signals.

19. The method of claim 16, further comprising:

driving a third set of the common electrodes for capacitive sensing during a third portion of the second display frame, the third set of the common electrodes including at least one common electrode not included in the first set of the common electrodes;

receiving fifth resulting signals during the third portion of the second display frame; and

determining the first capacitive frame based on at least a portion of the fifth resulting signals.

20. The method of claim 16, wherein operating the plurality of common electrodes in a substantially non-modulating manner for interference sensing during the second portion of first display frame and during the second portion of the second display frame comprises one of driving the plurality of common electrodes with a substantially constant voltage and electrically floating the plurality of common electrodes.

21. A processing system for a display device with an integrated capacitive sensing device comprising:

a driver module configured to be coupled to a plurality of common electrodes configured for capacitive sensing and display updating, the driver module configured for;

driving the plurality of common electrodes for display updating during a first display frame;

driving a first set of common electrodes included in the plurality of common electrodes for capacitive sensing during a first portion of the first display frame, wherein a second set of common electrodes included in the plurality of common electrodes is not driven for capacitive sensing during the first display frame; and

operating one or more of the plurality of common electrodes in a substantially non-modulating manner for interference sensing during a second portion of the first display frame that corresponds to a duration of time during which the second set of common electrodes are driven for capacitive sensing during a second display frame;

a receiver module configured to be communicatively coupled to the plurality of receiver electrodes, the receiver module configured for;

receiving first resulting signals during the first portion of the first display frame; and

receiving second resulting signals during the second portion of the first display frame; and

a determination module configured for determining at least portion of a first capacitive frame based on the first resulting signals and an interference measurement corresponding to the first capacitive frame based on the second resulting signals.