Full in-cell sensor

• US 9,652,072 B2
• Filed: 10/02/2015
• Issued: 05/16/2017
• 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:
  US14/873,902
• Publication Number:
  US 20160026330A1
• Time in Patent Office: 592 Days
• Field of Search: 178 1801- 1907, 345173-178
• 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 processing system for a display device having an integrated sensing device, the processing system comprising:

a driver module comprising driver circuitry, the driver module configured to couple to a plurality of sensor electrodes, wherein the plurality of sensor electrodes comprise an array of rectangles including at least one transmitter electrode and at least one receiver electrode, and configured to;

drive a first sensor electrode of the plurality of sensor electrodes for absolute capacitive sensing during a first period to acquire first resulting signals; and

drive a second sensor electrode of the plurality of sensor electrodes with a varying voltage signal during a second period to reduce the capacitive coupling between the second sensor electrode and at least one other sensor electrode of the plurality of sensor electrodes,

wherein the first period and the second period are at least partially overlapping;

wherein the second sensor electrode comprises a second transmitter electrode and the at least one other sensor electrode comprises a receiver electrode;

wherein each of the plurality of sensor electrodes comprises at least one of a plurality of common electrode segments configured to be driven for display updating and capacitive sensing; and

wherein the processing system is configured to determine positional information for an input object based on the resulting signals.

2. The processing system of claim 1, wherein the driver module is further configured to drive the second sensor electrode for capacitive sensing during a third period and drive the first sensor electrode with a varying voltage during a fourth period, wherein the third period at least partially overlaps with the fourth period.

3. The processing system of claim 1, wherein driving the first sensor electrode for capacitive sensing comprises driving the first sensor electrode with a transmitter signal and receiving the resulting signals with a third sensor electrode of the plurality of sensor electrodes.

4. The processing system of claim 1, wherein the processing system comprises a first controller communicatively coupled to a second controller.

5. The processing system of claim 1, wherein the processing system comprises a single controller.

6. An input device comprising:

a plurality of sensor electrodes, wherein each sensor electrode of the plurality of sensor electrodes comprise at least one common electrode segments of a plurality of common electrode segments of a display device, wherein the plurality of common electrodes are configured to be driven for display updating and capacitive sensing, and wherein the plurality of sensor electrodes comprise an array of rectangles including at least one transmitter electrode and at least one receiver electrode; and

a processing system configured to couple to the plurality of sensor electrodes and configured to;

drive a first sensor electrode of the plurality of sensor electrode for absolute capacitive sensing during a first period to acquire first resulting signals,

drive a second sensor electrode of the plurality of sensor electrodes with a varying voltage signal during a second period to reduce the capacitive coupling between the second sensor electrode and at least one other sensor electrode of the plurality of sensor electrodes, wherein the first period and the second period are at least partially overlapping, and wherein the second sensor electrode comprises a second transmitter electrode and the at least one other sensor electrode comprises a receiver electrode; and

determine positional information for an input object based on the resulting signals.

7. The input device of claim 6, wherein the processing system is further configured to drive the second sensor electrode for capacitive sensing during a third period and drive the first sensor electrode with a varying voltage during a fourth period, wherein the third period at least partially overlaps with the fourth period.

8. The input device of claim 6, wherein driving the first sensor electrode for capacitive sensing comprises driving the first sensor electrode with a transmitter signal and receiving the resulting signals with a third sensor electrode of the plurality of sensor electrodes.

9. The input device of claim 8, wherein the third sensor electrode is disposed on a color filter glass of the display device.

10. The input device of claim 6, wherein the array of rectangles comprises rectangles of a same size and shape.

11. The input device of claim 6, wherein each sensor electrode of the plurality of sensor electrodes comprises a first plurality of common electrode segments interleaved with a second plurality of common electrode segments, and wherein the first plurality of common electrode segments is configured to be driven for display updating and the second plurality of common electrode segments are not driven for capacitive sensing.

12. The input device of claim 6, further comprising:

a plurality of ground electrodes, wherein each ground electrode comprises at least one common electrode segment of the plurality of common electrode segments, and wherein at least one ground electrode is disposed between two sensor electrodes of the plurality of sensor electrodes.

13. The input device of claim 6, wherein the processing system comprises a single controller configured to drive the first sensor electrode and the second sensor electrode and determine the positional information.

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

driving a first sensor electrode of a plurality of sensor electrodes for absolute capacitive sensing during a first period to acquire first resulting signals, wherein the plurality of sensor electrodes comprise an array of rectangles including at least one transmitter electrode and at least one receiver electrode;

driving a second sensor electrode of the plurality of sensor electrodes with a varying voltage signal during a second period to reduce the capacitive coupling between the second sensor electrode and at least one other sensor electrode of the plurality of sensor electrodes, wherein the first period and the second period are at least partially overlapping, wherein the second sensor electrode comprises a second transmitter electrode and the at least one other sensor electrode comprises a receiver electrode, and wherein each of the plurality of sensor electrodes comprises at least one of a plurality of common electrode segments configured to be driven for display updating and capacitive sensing; and

determining positional information for an input object based on the resulting signals.

15. The method of claim 14, further comprising:

driving the second sensor electrode for capacitive sensing during a third period and driving the first sensor electrode with a varying voltage during a fourth period, wherein the third period at least partially overlaps with the fourth period.

16. The method of claim 14, wherein driving the first sensor electrode for capacitive sensing comprises driving the first sensor electrode with a transmitter signal and receiving the resulting signals with a third sensor electrode of the plurality of sensor electrodes.