SINGLE-LAYER SENSOR ARRAY SCAN

• US 20200133409A1
• Filed: 10/27/2018
• Published: 04/30/2020
• Est. Priority Date: 10/27/2018
• Status: Active Grant

• Current Assignee: Synaptics Incorporated
• Original Assignee: Synaptics Incorporated
• Inventors: TANEMURA, Tetsuo
• Granted Patent: US 10,649,600 B1
• Time in Patent Office: Days
• CPC Class Codes: G06F 2203/04108 Touchless 2D- digitiser, i.e. digitiser detecting the X/Y position of the input means, finger or stylus, also when it does not touch, but is proximate to the digitiser's interaction surface without distance measurement in the Z direction
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/0416 Control or interface arrangements specially adapted for digitisers
• 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 3/0443 using a single layer of sensing electrodes

Abstract

A method of performing a scan of a sensor array is disclosed, as well as an associated processing system and input device. The sensor array comprises a plurality of sensor electrodes in a single layer. A plurality of routing traces is arranged in the single layer. The method comprises, for each sensor electrode of the plurality of sensor electrodes, acquiring, during a first period, an absolute capacitive measurement for the sensor electrode. The method further comprises, for each bordering sensor electrode of one or more bordering sensor electrodes of the plurality of sensor electrodes, acquiring, during a second period, a transcapacitive measurement between the sensor electrode and the bordering sensor electrode.

Claims

1. An input device comprising:

a sensor array comprising a plurality of sensor electrodes in a single layer of the input device, wherein each sensor electrode of the plurality of sensor electrodes is bordered by one or more bordering sensor electrodes of the plurality of sensor electrodes;

a plurality of routing traces arranged in the single layer; and

a processing system coupled with the plurality of sensor electrodes via the plurality of routing traces, the processing system configured to perform a scan of the sensor array by operating each sensor electrode of the plurality of sensor electrodes to;

acquire, during a first period, an absolute capacitive measurement for the sensor electrode; and

for each bordering sensor electrode of the one or more bordering sensor electrodes;

acquire, during a second period, a transcapacitive measurement between the sensor electrode and the bordering sensor electrode.

2. The input device of claim 1, wherein the processing system is further configured to, according to a predefined sequence:

drive a first plurality of transmitter groups with a modulated signal during a first sub-period of the second period, wherein each transmitter group of the first plurality of transmitter groups comprises a plurality of contiguous sensor electrodes of the plurality of sensor electrodes and is spaced apart from other transmitter groups of the first plurality of transmitter groups; and

drive a second plurality of transmitter groups with a modulated signal during a second sub-period of the second period, wherein each transmitter group of the second plurality of transmitter groups comprises a plurality of contiguous sensor electrodes of the plurality of sensor electrodes and is spaced apart from other transmitter groups of the second plurality of transmitter groups.

3. The input device of claim 2, wherein according to the predefined sequence, a single transcapacitive measurement is acquired for each combination of a particular sensor electrode and a bordering sensor electrode of the one or more bordering sensor electrodes.

4. The input device of claim 2, wherein the plurality of contiguous sensor electrodes of each transmitter group of the first plurality of transmitter groups and of each transmitter group of the second plurality of transmitter groups comprises:

two sensor electrodes that are contiguous along a first axis of the sensor array; and

two sensor electrodes that are contiguous along a second axis of the sensor array.

5. The input device of claim 4, wherein, within the first plurality of transmitter groups and within the second plurality of transmitter groups, different transmitter groups are separated by two sensor electrodes along the first axis and by two sensor electrodes along the second axis.

6. The input device of claim 1, wherein the processing system is further configured to, according to a predefined sequence:

drive first sensor electrodes of the plurality of sensor electrodes with a modulated signal during a first sub-period of the second period;

drive second sensor electrodes of the plurality of sensor electrodes with a modulated signal during a second sub-period of the second period; and

perform one or more matrix operations to acquire the transcapacitive measurement between the sensor electrode and the bordering sensor electrode.

7. The input device of claim 6, wherein the processing system is further configured to, according to the predefined sequence:

drive third sensor electrodes of the plurality of sensor electrodes with a modulated signal during a third sub-period of the second period,

wherein the first sensor electrodes are contiguous along a first axis of the sensor array,

wherein the second sensor electrodes are contiguous along a second axis of the sensor array,

wherein the third sensor electrodes comprise alternating sensor electrodes of the sensor array, and

wherein the one or more matrix operations comprise at least one of matrix addition or matrix subtraction.

8. The input device of claim 1, wherein during the first period, the plurality of sensor electrodes is contemporaneously driven with a same modulated signal.

9. The input device of claim 1, wherein the sensor array comprises a rectangular array of M rows of sensor electrodes and N columns of sensor electrodes.

10. A processing system comprising:

sensing circuitry configured to;

couple with a sensor array via a plurality of routing traces, wherein the sensor array comprises a plurality of sensor electrodes in a single layer, wherein each sensor electrode of the plurality of sensor electrodes is bordered by one or more bordering sensor electrodes of the plurality of sensor electrodes, wherein the plurality of routing traces is arranged in the single layer; and

perform a scan of the sensor array by operating each sensor electrode of the plurality of sensor electrodes to;

acquire, during a first period, an absolute capacitive measurement for the sensor electrode; and

for each bordering sensor electrode of the one or more bordering sensor electrodes;

acquire, during a second period, a transcapacitive measurement between the sensor electrode and the bordering sensor electrode.

11. The processing system of claim 10, wherein the sensing circuitry is further configured to, according to a predefined sequence:

drive a first plurality of transmitter groups with a modulated signal during a first sub-period of the second period, wherein each transmitter group of the first plurality of transmitter groups comprises a plurality of contiguous sensor electrodes of the plurality of sensor electrodes and is spaced apart from other transmitter groups of the first plurality of transmitter groups; and

drive a second plurality of transmitter groups with a modulated signal during a second sub-period of the second period, wherein each transmitter group of the second plurality of transmitter groups comprises a plurality of contiguous sensor electrodes of the plurality of sensor electrodes and is spaced apart from other transmitter groups of the second plurality of transmitter groups.

12. The processing system of claim 11, wherein according to the predefined sequence, a single transcapacitive measurement is acquired for each combination of a particular sensor electrode and a bordering sensor electrode of the one or more bordering sensor electrodes.

13. The processing system of claim 10, wherein the sensing circuitry is further configured to, according to a predefined sequence:

drive first sensor electrodes of the plurality of sensor electrodes with a modulated signal during a first sub-period of the second period;

drive second sensor electrodes of the plurality of sensor electrodes with a modulated signal during a second sub-period of the second period; and

perform one or more matrix operations to acquire the transcapacitive measurement between the sensor electrode and the bordering sensor electrode.

15. The processing system of claim 10, wherein during the first period, the plurality of sensor electrodes is contemporaneously driven with a same modulated signal.

16. The processing system of claim 10, wherein the sensor array and the plurality of routing traces are arranged in the single layer of an input device, wherein the input device further comprises a display device, the processing system further comprising:

display driver circuitry configured to update the display device.

17. The processing system of claim 16, wherein each of the plurality of sensor electrodes comprises at least one common electrode of a plurality of common electrodes of the display device, wherein the plurality of common electrodes are configured to perform capacitive sensing and display updating.

14. The processing system of claim 14, wherein the sensing circuitry is further configured to, according to the predefined sequence:

drive third sensor electrodes of the plurality of sensor electrodes with a modulated signal during a third sub-period of the second period,

wherein the first sensor electrodes are contiguous along a first axis of the sensor array,

wherein the second sensor electrodes are contiguous along a second axis of the sensor array,

wherein the third sensor electrodes comprise alternating sensor electrodes of the sensor array, and

wherein the one or more matrix operations comprise at least one of matrix addition or matrix subtraction.

18. A method of performing a scan of a sensor array of an input device, the sensor array comprising a plurality of sensor electrodes in a single layer of the input device, the input device further comprising a plurality of routing traces arranged in the single layer, the method comprising:

for each sensor electrode of the plurality of sensor electrodes;

acquiring, during a first period, an absolute capacitive measurement for the sensor electrode; and

for each bordering sensor electrode of one or more bordering sensor electrodes of the plurality of sensor electrodes;

acquiring, during a second period, a transcapacitive measurement between the sensor electrode and the bordering sensor electrode.

19. The method of claim 18, wherein acquiring the transcapacitive measurement comprises, according to a predefined sequence:

driving a first plurality of transmitter groups with a modulated signal during a first sub-period of the second period, wherein each transmitter group of the first plurality of transmitter groups comprises a plurality of contiguous sensor electrodes of the plurality of sensor electrodes and is spaced apart from other transmitter groups of the first plurality of transmitter groups; and

driving a second plurality of transmitter groups with a modulated signal during a second sub-period of the second period, wherein each transmitter group of the second plurality of transmitter groups comprises a plurality of contiguous sensor electrodes of the plurality of sensor electrodes and is spaced apart from other transmitter groups of the second plurality of transmitter groups.

20. The method of claim 18, wherein acquiring the transcapacitive measurement comprises, according to a predefined sequence:

driving first sensor electrodes of the plurality of sensor electrodes with a modulated signal during a first sub-period of the second period;

driving second sensor electrodes of the plurality of sensor electrodes with a modulated signal during a second sub-period of the second period; and

performing one or more matrix operations to acquire the transcapacitive measurement between the sensor electrode and the bordering sensor electrode.