SENSING FORCE USING TRANSCAPACITANCE WITH DEDICATED FORCE RECEIVER ELECTRODES

• US 20160334903A1
• Filed: 09/30/2015
• Published: 11/17/2016
• Est. Priority Date: 05/12/2015
• Status: Active Grant

• Current Assignee: Synaptics Incorporated
• Original Assignee: Synaptics Incorporated
• Inventors: SHEPELEV, Petr
• Granted Patent: US 9,965,118 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 2203/04105 Pressure sensors for measuring the pressure or force exerted on the touch surface without providing the touch position
• CPC Class Codes: G06F 2203/04106 Multi-sensing digitiser, i.e. digitiser using at least two different sensing technologies simultaneously or alternatively, e.g. for detecting pen and finger, for saving power or for improving position detection
• 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 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes

Abstract

An example integrated display device and capacitive sensing device having an input surface includes a plurality of sensor electrodes, wherein each of the plurality of sensor electrodes comprises at least one common electrode configured for display updating and capacitive sensing. The device further includes at least one force receiver electrode, wherein the plurality of sensor electrodes are disposed between the input surface and the at least one force receiver electrode and wherein at least a portion of the plurality of sensor electrodes are configured to deflect toward the at least one force receiver electrode. The device further includes a processing system, coupled to the plurality of sensor electrodes, configured to drive at least a portion of the plurality of sensor electrodes with force sensing signals while receiving resulting signals from the at least one force receiver electrode, and determine force information for an input object based on the resulting signals.

Claims

1. An integrated display device and capacitive sensing device having an input surface, comprising:

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

at least one force receiver electrode, wherein the plurality of sensor electrodes are disposed between the input surface and the at least one force receiver electrode and wherein at least a portion of the plurality of sensor electrodes are configured to deflect toward the at least one force receiver electrode;

a processing system, coupled to the plurality of sensor electrodes, configured to;

drive at least a portion of the plurality of sensor electrodes with force sensing signals while receiving resulting signals from the at least one force receiver electrode; and

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

2. The device of claim 1, wherein the at least one force receiver electrode comprises a plurality of force receiver electrodes.

3. The device of claim 1, wherein each of the at least one force receiver electrode is disposed perpendicular to the plurality of sensor electrodes.

4. The device of claim 1, wherein the processing system is configured to operate at least a portion of the plurality of sensor electrodes to detect changes in absolute capacitance and determine positional information of the input object based on the changes in absolute capacitance.

5. The device of claim 1, further comprising:

a plurality of receiver electrodes;

wherein the processing system is configured to;

drive the plurality of sensor electrodes with transmitter signals while receiving resulting signals from the plurality of receiver electrodes; and

determine positional information of the input object proximate the input surface based on the resulting signals from the plurality of receiver electrodes.

6. The device of claim 1, wherein the plurality of sensor electrodes comprise a plurality of transmitter electrodes and a plurality of receiver electrodes, and wherein the processing system is configured to:

drive the plurality of transmitter electrodes with transmitter signals while receiving resulting signals from the plurality of receiver electrodes; and

determine positional information of an input object proximate the input surface based on the resulting signals from the plurality of receiver electrodes.

7. The device of claim 1, wherein the processing system is configured to drive at least a portion of the plurality of sensor electrodes with force sensing signals during a non-display update time.

8. The device of claim 1, further comprising:

thin-film transistor (TFT) glass disposed below the plurality of sensor electrodes;

wherein the at least one force receiver electrode is disposed below the TFT glass.

9. The device of claim 8, further comprising:

a backlight disposed below the TFT glass;

wherein the at least one force receiver electrode is disposed below the backlight.

10. A processing system for an integrated display device and capacitive sensing device having an input surface, the processing system comprising:

a sensor module including sensor circuitry coupled to a plurality of sensor electrodes and at least one force receiver electrode, the plurality of sensor electrodes being disposed between the input surface and the at least one force receiver electrode, at least a portion of the plurality of sensor electrodes configured to deflect toward the at least one force receiver electrode, the sensor circuitry configured to drive at least a portion of the plurality of sensor electrodes with force sensing signals while receiving resulting signals from the at least one force receiver electrode; and

a processing circuit, coupled to the sensor circuitry, configured to determine force information for an input object based on the resulting signals.

11. The processing system of claim 10, wherein the at least one force receiver electrode comprises a plurality of force receiver electrodes.

12. The processing system of claim 10, wherein each of the at least one force receiver electrode is disposed perpendicular to the plurality of sensor electrodes.

13. The processing system of claim 10, wherein the processing circuit is configured to detect changes in absolute capacitance of at least a portion of the plurality of sensor electrodes and determine positional information of the input object based on the changes in absolute capacitance.

14. The processing system of claim 10, wherein the sensor circuitry is further coupled to a plurality of receiver electrodes, wherein the sensor circuitry is configured to drive the plurality of sensor electrodes with transmitter signals while receiving resulting signals from the plurality of receiver electrodes, and wherein the processing circuit is configured to determine positional information of the input object based on the resulting signals from the plurality of receiver electrodes.

15. The processing system of claim 10, wherein the plurality of sensor electrodes comprise a plurality of transmitter electrodes and a plurality of receiver electrodes, wherein the sensor circuitry is configured to drive the plurality of transmitter electrodes with transmitter signals while receiving resulting signals from the plurality of receiver electrodes, and wherein the processing circuit is configured to determine positional information of the input object based on the resulting signals from the plurality of receiver electrodes.

16. The processing system of claim 10, wherein the sensor circuitry is configured to drive at least a portion of the plurality of sensor electrodes with force sensing signals during a non-display update time.

17. A method of operating an integrated display device and capacitive sensing device having a plurality of sensor electrodes disposed between an input surface and at least one force receiver electrode, at least a portion of the plurality of sensor electrodes configured to deflect toward the at least one force receiver electrode, each of the plurality of sensor electrodes comprising at least one common electrode configured for display updating and capacitive sensing, the method comprising:

driving at least a portion of the plurality of sensor electrodes with force sensing signals while receiving resulting signals from the at least one force receiver electrode; and

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

18. The method of claim 17, further comprising:

driving at least a portion of the plurality of sensor electrodes to detect changes in absolute capacitance and determine positional information of the input object based on the changes in absolute capacitance.

19. The method of claim 17, wherein the integrated display device and capacitive sensing device includes a plurality of receiver electrodes, the method further comprising:

driving the plurality of sensor electrodes with transmitter signals while receiving resulting signals from the plurality of receiver electrodes; and

determining positional information of the input object proximate the input surface based on the resulting signals from the plurality of receiver electrodes.

20. The method of claim 17, wherein the plurality of sensor electrodes comprise a plurality of transmitter electrodes and a plurality of receiver electrodes, and wherein the method further comprises:

driving the plurality of transmitter electrodes with transmitter signals while receiving resulting signals from the plurality of receiver electrodes; and

determining positional information of an input object proximate the input surface based on the resulting signals from the plurality of receiver electrodes.