Full in-cell sensor

• US 9,152,283 B2
• Filed: 06/27/2013
• Issued: 10/06/2015
• Est. Priority Date: 06/27/2013
• Status: Active Grant

• Current Assignee: Synaptics Incorporated
• Original Assignee: Synaptics Incorporated
• Inventors: Shepelev, Petr, Mackin, Thomas, Hoch, David
• Primary Examiner(s): Pervan, Michael
• Application Number:
  US13/929,680
• Publication Number:
  US 20150002752A1
• Time in Patent Office: 831 Days
• US Class Current: 1/1
• CPC Class Codes: G01R 27/2605 Measuring capacitance capacitive sensors G01D5/24
• CPC Class Codes: G06F 2203/04107 Shielding in digitiser, i.e. guard or shielding arrangements, mostly for capacitive touchscreens, e.g. driven shields, driven grounds
• 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 3/04184 Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally
• 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 display device having an integrated capacitive sensing device includes receiver electrodes disposed on a back side of a color filter glass. Transmitter electrodes of the capacitive sensing device are configured with a size and geometry that reduces the capacitive coupling between the transmitter and receiver electrodes. The transmitter electrodes may be made of one or more prongs or segments from a segmented common electrode.

Claims

1. A display device comprising an integrated capacitive sensing device, the display device comprising:

a plurality of transmitter electrodes disposed on a first substrate, each transmitter electrode comprising a first plurality of common electrode segments interleaved with a second plurality of common electrode segments, wherein the first plurality of common electrode segments is configured to be driven for display updating and capacitive sensing;

a second substrate;

a region defined between the first substrate and the second substrate, wherein the region comprises a plurality of color filters, a black mask, and a plurality of receiver electrodes, wherein the plurality of receiver electrodes are aligned with regions defined between adjacent color filters; and

a processing system coupled to the plurality of transmitter electrodes and the plurality of receiver electrodes, wherein the processing system is configured to;

drive the first plurality of common electrode segments of a first transmitter electrode with a transmitter signal;

receive resulting signals with at least one receiver electrode, the resulting signals comprising effects corresponding to the transmitter signal, wherein the first plurality of common electrode segments is capacitively coupled with the receiver electrode forming a transcapacitive coupling; and

while driving the first plurality of common electrode segments, the second plurality of common electrode segments are configured to reduce the transcapacitive coupling between the first plurality of common electrode segments and the receiver electrode.

2. The display device of claim 1, wherein the second plurality of common electrode segments are configured to reduce the transcapacitive coupling between the first plurality of common electrode segments and the receiver electrode comprises:

driving the second plurality of common electrode segments with a substantially constant voltage, while driving the first plurality of common electrode segments with the transmitter signal.

3. The display device of claim 1, wherein the second plurality of common electrode segments are configured to reduce the transcapacitive coupling between the first plurality of common electrode segments and the receiver electrode comprises:

electrically floating the second plurality of common electrode segments, while driving the first plurality of common electrode segments with the transmitter signal.

4. The display device of claim 1, wherein the second plurality of common electrode segments are configured to reduce the transcapacitive coupling between the first plurality of common electrode segments and the receiver electrode comprises:

driving the second plurality of common electrode segments with a varying voltage, while driving the first plurality of common electrode segments with the transmitter signal.

5. The display device of claim 1, wherein the second plurality of common electrode segments overlap at least one of the plurality of receiver electrodes, and wherein the first plurality of common electrode segments of a transmitter electrode are electrically coupled through a plurality of jumpers.

6. The display device of claim 1, wherein the plurality of receiver electrodes comprise a non-transparent, non-reflective, conductive black mask material.

7. The display device of claim 1, wherein the plurality of receiver electrodes comprises non-transparent, conductive traces aligned with a portion of the black mask.

8. The display device of claim 7, wherein the plurality of receiver electrodes comprises at least one disused receiver electrode, wherein the disused receiver electrode comprises a plurality of segments of non-transparent conductive trace aligned with a portion of the black mask, each segment electrically insulated from other segments and overlapping only a single transmitter electrode.

9. The display device of claim 1, wherein the plurality of receiver electrodes are coupled to the processing system through a plurality of silver ball connectors.

10. The display device of claim 1, wherein the processing system is further configured to electrically float the plurality of receiver electrodes while the first plurality of common electrode segments are driven for display updating during a display update period of a display frame.

11. The display device of claim 10, wherein the processing system is further configured to drive the plurality of receiver electrodes with an offset voltage that drains charge buildup during a capacitive sensing period of the display frame, wherein the capacitive sensing period comprises at least one non-display update periods.

12. A touch sensor for a display device having an integrated capacitive sensing device, the touch sensor comprising:

a plurality of transmitter electrodes disposed on a first substrate, each transmitter electrode comprising a first plurality of common electrode segments interleaved with a second plurality of common electrode segments, wherein the first plurality of common electrode segments is configured to be driven for display updating and capacitive sensing and wherein the second plurality of common electrode segments are not driven for capacitive sensing;

a second substrate;

a display material disposed between the first substrate and the second substrate, wherein the plurality of transmitter electrodes are disposed between the first substrate and the display material;

a region defined between the second substrate and the display material, wherein the region comprises a plurality of color filters, a black mask, and a plurality of receiver electrodes, wherein the plurality of receiver electrodes are disposed between the second substrate and the display material and are aligned with regions defined between adjacent color filters.

13. The touch sensor of claim 12, wherein the second plurality of common electrode segments overlap at least one of the plurality of receiver electrodes;

and wherein the first plurality of common electrode segments of a transmitter electrode are electrically coupled through a plurality of jumpers.

14. The touch sensor of claim 12, wherein the plurality of receiver electrodes comprises a non-transparent, non-reflective, conductive black mask material.

15. The touch sensor of claim 12, wherein the plurality of receiver electrodes comprises non-transparent, conductive traces aligned with a portion of the black mask.

16. The touch sensor of claim 12, wherein the plurality of receiver electrodes comprises at least one disused receiver electrode, wherein the disused receiver electrode comprises a plurality of segments of non-transparent conductive trace aligned with a portion of the black mask, each segment electrically insulated from other segments and overlapping only a single transmitter electrode.

17. The touch sensor of claim 12, wherein the plurality of transmitter electrodes and the plurality of receiver electrodes have double connections to a processing system.

18. A method for operating a display device having an integrated capacitive sensing device, the method comprising:

driving a first plurality of common electrode segments of a first transmitter electrode with a transmitter signal, wherein the first plurality of common electrode segments is configured to be driven for display updating and capacitive sensing; and

receiving resulting signals with at least one receiver electrode, the resulting signals comprising effects corresponding to the transmitter signal, wherein the first plurality of common electrode segments is capacitively coupled with the receiver electrode forming a transcapacitive coupling,

wherein the receiver electrode is disposed in a region defined between a first substrate and a second substrate, wherein the region further comprises a black mask, and a plurality of color filters, wherein the receiver electrode is aligned with a region defined between adjacent color filters; and

while driving the first plurality of common electrode segments, a second plurality of common electrode segments are configured to reduce the transcapacitive coupling between the first plurality of common electrode segments and the receiver electrode, wherein the first plurality of common electrode segments is interleaved with the second plurality of common electrode segments.

19. The method of claim 18, wherein the second plurality of common electrode segments configured to reduce the transcapacitive coupling between the first plurality of common electrode segments and the receiver electrode further comprises:

driving the second plurality of common electrode segments with a substantially constant voltage while driving the first plurality of common electrode segments with the transmitter signal.

20. The method of claim 18, wherein the second plurality of common electrode segments configured to reduce the transcapacitive coupling between the first plurality of common electrode segments and the receiver electrode comprises:

electrically floating the second plurality of common electrode segments while driving the first plurality of common electrode segments with the transmitter signal.

21. The method of claim 18, wherein the second plurality of common electrode segments configured to reduce the transcapacitive coupling between the first plurality of common electrode segments and the receiver electrode comprises:

driving the second plurality of common electrode segments with a varying voltage while driving the first plurality of common electrode segments with the transmitter signal.

22. The method of claim 18, further comprising:

electrically floating the at least one receiver electrode while the first plurality of common electrode segments are driven for display updating during a display update period of a display frame.

23. The method of claim 18, further comprising:

driving the at least one receiver electrode with an offset voltage that drains charge buildup during a capacitive sensing period of the display frame, wherein the capacitive sensing period comprises a plurality of non-display update periods.

24. The method of claim 18, further comprising:

driving the at least one receiver electrode with a substantially constant voltage during updating of the display device.

25. The method of claim 18, further comprising:

electrically floating the at least one receiver electrode during updating of the display device.