Capacitive sensing using a segmented common voltage electrode of a display

• US 8,643,624 B2
• Filed: 03/17/2010
• Issued: 02/04/2014
• Est. Priority Date: 03/18/2009
• Status: Active Grant

• Current Assignee: Synaptics Incorporated
• Original Assignee: Synaptics Incorporated
• Inventors: Day, Shawn P., Mackey, Bob Lee, Reynolds, Joseph Kurth
• Primary Examiner(s): CERULLO, LILIANA P
• Application Number:
  US12/726,322
• Publication Number:
  US 20100238134A1
• Time in Patent Office: 1,420 Days
• Field of Search: 345173-184, 345 87-101, 178 1801- 1903, 349/12
• US Class Current: 345/174
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/04166 Details of scanning methods, e.g. sampling time, grouping of sub areas or time sharing with display driving Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally G06F3/04184
• CPC Class Codes: G06F 3/044 by capacitive means
• 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

An integrated display and touch sensor device comprises a plurality of display pixels and a processing system communicatively coupled with a plurality of common voltage electrode segments and with a plurality of receiver sensor electrodes. The plurality of display pixels is configured for displaying information on the display. The processing system is configured for driving a voltage transition onto a common voltage electrode segment of the plurality of common voltage electrode segments. The voltage transition provides a common voltage for refreshing at least one display pixel of the plurality of display pixels, and generates a first electrical signal on at least one receiver sensor electrode of the plurality of receiver sensor electrodes. The processing system is also configured for acquiring a first measurement of a capacitive coupling between the driven common voltage electrode segment and the at least one receiver sensor electrode by measuring the first electrical signal.

Claims

1. An integrated display and touch sensor device comprising:

a plurality of common voltage electrode segments;

a plurality of display pixels configured for displaying information on said display;

a plurality of receiver sensor electrodes; and

a processing system communicatively coupled with said plurality of common voltage electrode segments and with said plurality of receiver sensor electrodes, wherein said processing system is configured for;

driving a voltage transition onto a common voltage electrode segment of said plurality of common voltage electrode segments, wherein said voltage transition comprises a transition from a first voltage to a second voltage, wherein said voltage transition provides a common voltage for refreshing at least one display pixel of said plurality of display pixels, and wherein said voltage transition simultaneously generates a first electrical signal on at least one receiver sensor electrode of said plurality of receiver sensor electrodes; and

acquiring a first measurement of a capacitive coupling between said common voltage electrode segment and said at least one receiver sensor electrode by measuring said first electrical signal.

2. The integrated display and touch sensor device of claim 1, wherein said processing system is further configured for:

determining positional information related to an input object based on said first measurement.

3. The integrated display and touch sensor device of claim 1, wherein said processing system is further configured for driving a second voltage transition onto a second common voltage electrode segment to provide a second common voltage for refreshing a second at least one display pixel of said plurality of display pixels, wherein said second voltage transition generates a second electrical signal on said at least one receiver sensor electrode of said plurality of receiver sensor electrodes, and wherein said driving a voltage transition and said driving a second voltage transition occur sequentially.

4. The integrated display and touch sensor device of claim 1, wherein said plurality of display pixels comprises first and second subsets of pixels and wherein said processing system is further configured for:

acquiring a first capacitive image during a first time period by driving a first plurality of voltage transitions, wherein said first plurality of voltage transitions comprises said voltage transition driven onto said common voltage electrode segment of said plurality of common voltage electrode segments, wherein at least one voltage transition of said first plurality of voltage transitions is driven onto each common voltage electrode segment of said plurality of common voltage electrode segments, and wherein said first plurality of voltage transitions provides a plurality of common voltages for refreshing said first subset of pixels; and

acquiring a second capacitive image during a second time period by driving a second plurality of voltage transitions, wherein at least one voltage transition of said second plurality of voltage transitions is driven onto each common voltage electrode segment of said plurality of common voltage electrode segments, wherein said second plurality of voltage transitions provides a plurality of common voltages for refreshing said second subset of pixels, and wherein said first and said second subset of pixels are different.

5. The integrated display and touch sensor device of claim 4, wherein said first subset of pixels includes all even pixel rows and said second subset of pixels includes all odd pixel rows.

6. The integrated display and touch sensor device of claim 1, wherein said plurality of display pixels are arranged in a plurality of pixel rows, wherein a first pixel row of said plurality of pixel rows comprises first and second subsets of pixels,

wherein said driving said voltage transition onto said common voltage electrode segment of said plurality of common voltage electrode segments comprises providing said common voltage for refreshing said first subset with a first polarity, and wherein said processing system is further configured for:

driving a second voltage transition to provide a second common voltage for refreshing said second subset with a second polarity, wherein said first and said second voltage transitions are sequentially driven.

7. The integrated display and touch sensor device of claim 1, wherein said plurality of display pixels is arranged in a plurality of pixel rows and wherein said common voltage electrode segment has a sufficient size to overlap more than one of said plurality of pixel rows.

8. The integrated display and touch sensor device of claim 1, wherein said plurality of common voltage electrode segments comprises a plurality of substantially parallel elongated shapes;

and

wherein said plurality of receiver sensor electrodes is disposed in a substantially orthogonal orientation to said plurality of common voltage electrode segments.

9. The integrated display and touch sensor device of claim 1, wherein said plurality of common voltage electrode segments is disposed on a first substrate and said plurality of receiver sensor electrodes is disposed on a second substrate.

10. The integrated display and touch sensor device of claim 9, wherein said second substrate is a polarizer of said display.

11. The integrated display and touch sensor device of claim 1, wherein said plurality of common voltage electrode segments is disposed upon a first surface of a substrate and said plurality of receiver sensor electrodes is disposed on a second surface of said substrate.

12. The integrated display and touch sensor device of claim 11, wherein said substrate is a color filter panel of said display.

13. The integrated display and touch sensor device of claim 1, wherein said plurality of common voltage electrode segments and said plurality of receiver sensor electrodes are disposed upon a first surface of a substrate.

14. The integrated display and touch sensor device of claim 13, wherein said substrate is a color filter panel of said display.

15. The integrated display and touch sensor device of claim 1, wherein said driving a voltage transition onto a common voltage electrode segment of said plurality of common voltage electrode segments comprises:

driving said voltage transition on a subset of more than one but less than all of said plurality of common voltage electrode segments during a first period of time.

16. A device comprising:

a plurality of receiver sensor electrodes;

a plurality of common voltage electrode segments, wherein a common voltage electrode segment of said plurality of common voltage electrode segments is configured to be driven with a voltage transition that provides a common voltage for refreshing a subset of display pixels of a display and wherein said voltage transition simultaneously generates a plurality of electrical signals on a plurality of receiver sensor electrodes, wherein said voltage transition comprises a transition from a first voltage to a second voltage; and

a processing system communicatively coupled with said plurality of receiver sensor electrodes, wherein said processing system is configured for;

acquiring a plurality of measurements of a plurality of capacitive couplings between said common voltage electrode segment and said plurality of receiver sensor electrodes by measuring said plurality of electrical signals; and

determining positional information related to an input object proximate to said display based on said plurality of measurements.

17. The device of claim 16, wherein display pixels of said display are arranged in a plurality of pixel rows and wherein said common voltage electrode segment has a sufficient size to overlap more than one of said plurality of pixel rows.

18. The device of claim 16, wherein said plurality of common voltage electrode segments comprises a plurality of substantially parallel elongated shapes;

and

wherein said plurality of receiver sensor electrodes is disposed in a substantially orthogonal orientation to said plurality of common voltage electrode segments.

19. The device of claim 16, wherein said plurality of common voltage electrode segments is disposed on a first substrate and said plurality of receiver sensor electrodes is disposed on a second substrate.

20. The device of claim 16, wherein said plurality of common voltage electrode segments and said plurality of receiver sensor electrodes are both disposed on the same substrate.

21. A method of capacitive sensing in a display, said method comprising:

driving a voltage transition onto at least one common voltage electrode segment of a plurality of common voltage electrode segments of said display, wherein said voltage transition comprises a transition from a first voltage to a second voltage, wherein said voltage transition provides a common voltage for refreshing at least one display pixel of a plurality of display pixels of said display, and wherein said voltage transition simultaneously generates a first electrical signal on at least one receiver sensor electrode of a plurality of receiver sensor electrodes;

acquiring a first measurement of a capacitive coupling between said at least one common voltage electrode segment and said at least one receiver sensor electrode by measuring said first electrical signal; and

determining positional information related to an input object proximate to said display based on said first measurement.

22. The method as recited in claim 21, further comprising driving a second voltage transition onto a second common voltage electrode segment to provide a second common voltage for refreshing a second at least one display pixel of said plurality of display pixels, wherein said second voltage transition generates a second electrical signal on at least one receiver sensor electrode of said plurality of receiver sensor electrodes, and wherein said driving a voltage transition and driving a second voltage transition occur sequentially.

23. The method as recited in claim 21, wherein said plurality of display pixels comprises first and second subsets of pixels, and wherein said method further comprises:

acquiring a first capacitive image during a first time period by driving a first plurality of voltage transitions, wherein said first plurality of voltage transitions comprises said voltage transition driven onto said at least one common voltage electrode segment of said plurality of common voltage electrode segments, wherein at least one voltage transition of said first plurality of voltage transitions is driven onto each common voltage electrode segment of said plurality of common voltage electrode segments, and wherein said first plurality of voltage transitions provides a plurality of common voltages for refreshing said first subset of pixels; and

acquiring a second capacitive image during a second time period by driving a second plurality of voltage transitions, wherein at least one voltage transition of said second plurality of voltage transitions is driven onto each common voltage electrode segment of said plurality of common voltage electrode segments, wherein said second plurality of voltage transitions provides a plurality of common voltages for refreshing said second subset of pixels, and wherein said first and said second subset of pixels are different.

24. The method as recited in claim 21, wherein said plurality of display pixels are arranged in a plurality of pixel rows, wherein a first pixel row of said plurality of pixel rows comprises first and second subsets of pixels, wherein said driving said voltage transition onto at least one common voltage electrode segment of said plurality of common voltage electrode segments comprises providing said common voltage for refreshing said first subset with a first polarity;

and wherein said method further comprises;

driving a second voltage transition to provide a second common voltage for refreshing said second subset with a second polarity, wherein said first and said second voltage transitions are sequentially driven.

25. The method as recited in claim 21, wherein said driving a voltage transition onto at least one common voltage electrode segment of a plurality of common voltage electrode segments of said display comprises:

driving said voltage transition on a subset of more than one but less than all of said plurality of common voltage electrode segments during a first period of time.