SYSTEM AND METHOD FOR DETECTING AN ACTIVE PEN WITH A MATRIX SENSOR

• US 20150338937A1
• Filed: 12/29/2014
• Published: 11/26/2015
• Est. Priority Date: 05/20/2014
• Status: Active Grant

• Current Assignee: Wacom Co Limited (Wacom)
• Original Assignee: Synaptics Incorporated
• Inventors: SHEPELEV, Petr, REYNOLDS, Joseph Kurth
• Granted Patent: US 9,690,397 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• 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 3/03545 Pens or stylus
• CPC Class Codes: G06F 3/041 Digitisers, e.g. for touch screens or touch pads, characterised by the transducing means
• 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 3/0442 using active external devices, e.g. active pens, for transmitting changes in electrical potential to be received by the digitiser
• CPC Class Codes: G06F 3/0443 using a single layer of sensing electrodes

Abstract

A processing system, input device, and method are disclosed to detect an active input device. The method includes operating a first portion of a plurality of sensor electrodes to receive an active input signal from an active input device, and operating a second portion of the plurality of sensor electrodes to receive capacitive sensing data corresponding to a passive input device. The first and second portions include at least one sensor electrode in common. The method also includes driving a plurality of display electrodes to update a display image, wherein the plurality of sensor electrodes includes at least one of the plurality of display electrodes.

Claims

1. A processing system, comprising:

a display module configured to drive a display signal onto a plurality of display electrodes for updating a display; and

a sensor module configured to communicate with a plurality of sensor electrodes, wherein the plurality of sensor electrodes includes at least one of the plurality of display electrodes, wherein the sensor module is configured to;

in a first mode of operation, operate a first portion of the plurality of sensor electrodes to receive an active input signal from an active input device, and

in a second mode of operation, operate a second portion of the plurality of sensor electrodes to receive capacitive sensing data corresponding to a passive input device, wherein the first and second portions include at least one sensor electrode in common.

2. The processing system of claim 1, wherein the plurality of sensor electrodes includes a first grid electrode disposed between first and second sensor electrodes of the plurality of sensor electrodes,

wherein operating the first portion of the plurality of sensor electrodes to receive the active input signal from the active input device includes driving the first grid electrode to determine a presence of the active input device, and

wherein operating the second portion of the plurality of sensor electrodes to receive capacitive sensing data corresponding to the passive input device comprises driving at least one of the first and second sensor electrodes to determine a position of the passive input device, and driving the first grid electrode to guard the at least one of the first and second sensor electrodes.

3. The processing system of claim 2, wherein the plurality of sensor electrodes includes a second grid electrode, and wherein driving the first grid electrode includes driving the first and second grid electrodes to form a plurality of rows and driving the first and second sensor electrodes to form a plurality of columns.

4. The processing system of claim 1, wherein the sensor module is further configured to, in the second mode of operation, select the second portion of the plurality of sensor electrodes to have a first spatial pitch different from a second spatial pitch of the first portion of the plurality of sensor electrodes operated to receive the active input signal during the first mode.

5. The processing system of claim 4, wherein the first spatial pitch is smaller than the second spatial pitch.

6. The processing system of claim 1, wherein operating the second portion of the plurality of sensor electrodes includes driving a capacitive sensing signal on the second portion of the plurality of sensor electrodes.

7. The processing system of claim 1, wherein the display module is further configured to update the display using each of the plurality of sensor electrodes.

8. An input device, comprising:

a plurality of sensor electrodes, wherein at least one of the plurality of sensor electrodes is operable to update a display image and to perform input sensing; and

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

in a first mode of operation, operate a first portion of the plurality of sensor electrodes to receive an active input signal from an active input device, and

in a second mode of operation, operate a second portion of the plurality of sensor electrodes to receive capacitive sensing data corresponding to a passive input device, wherein the first and second portions include at least one sensor electrode in common.

9. The input device of claim 8, wherein the plurality of sensor electrodes includes a plurality of matrix electrodes disposed in a matrix arrangement.

10. The input device of claim 8, wherein the plurality of sensor electrodes includes a first grid electrode disposed between first and second sensor electrodes of the plurality of sensor electrodes,

wherein operating the first portion of the plurality of sensor electrodes to receive the active input signal from the active input device includes driving the first grid electrode to determine a presence of the active input device, and

wherein operating the second portion of the plurality of sensor electrodes to receive capacitive sensing data corresponding to the passive input device comprises driving at least one of the first and second sensor electrodes to determine a position of the passive input device, and driving the first grid electrode to guard the at least one of the first and second sensor electrodes.

11. The input device of claim 10, wherein the plurality of sensor electrodes includes a second grid electrode, and wherein driving the first grid electrode includes driving the first and second grid electrodes to form a plurality of rows and driving a first plurality of the plurality of sensor electrodes to form a plurality of columns.

12. The input device of claim 8, wherein the processing system is further configured to select the first portion of the plurality of sensor electrodes to have a first spatial pitch, and is further configured to select the second portion of the plurality of sensor electrodes to have a second spatial pitch that is smaller than the first spatial pitch.

13. The input device of claim 8, wherein operating the second portion of the plurality of sensor electrodes in the second mode of operation includes driving a capacitive sensing signal on the second portion of the plurality of sensor electrodes.

14. The input device of claim 8, wherein the plurality of sensor electrodes includes at least one common Vcom electrodes.

15. A method, comprising:

in a first mode of operation, operating a first portion of a plurality of sensor electrodes to receive an active input signal from an active input device;

in a second mode of operation, operating a second portion of the plurality of sensor electrodes to receive capacitive sensing data corresponding to a passive input device, wherein the first and second portions include at least one sensor electrode in common; and

in a third mode of operation, driving a plurality of display electrodes to update a display image, wherein the plurality of sensor electrodes includes at least one of the plurality of display electrodes.

16. The method of claim 15, wherein at least some of the plurality of sensor electrodes are disposed in a matrix arrangement.

17. The method of claim 15, wherein the plurality of sensor electrodes includes a first grid electrode disposed between first and second sensor electrodes of the plurality of sensor electrodes, and wherein operating the plurality of sensor electrodes includes:

driving the first grid electrode to determine a presence of the active input device, and

driving at least one of the first and second sensor electrodes to determine a position of the passive input device, and driving the first grid electrode to guard the at least one of the first and second sensor electrodes.

18. The method of claim 17, wherein the plurality of sensor electrodes includes a second grid electrode, and wherein driving the first grid electrode includes driving the first and second grid electrodes to form a plurality of rows and driving the first and second sensor electrodes to form a plurality of columns.

19. The method of claim 15, wherein operating the first portion of the plurality of sensor electrodes includes selecting the first portion of the plurality of sensor electrodes to have a first spatial pitch, and wherein operating the second portion of the plurality of sensor electrodes includes selecting the second portion of the plurality of sensor electrodes to have a second spatial pitch smaller than the first spatial pitch.

20. The method of claim 15, wherein operating the second portion of the plurality of sensor electrodes includes driving a capacitive sensing signal on the second portion of the plurality of sensor electrodes.