Detecting an active pen using a capacitive sensing device

• US 10,175,827 B2
• Filed: 12/23/2014
• Issued: 01/08/2019
• Est. Priority Date: 12/23/2014
• Status: Active Grant

• Current Assignee: Wacom Co Limited (Wacom)
• Original Assignee: Synaptics Incorporated
• Inventors: Shepelev, Petr, Schwartz, Adam
• Primary Examiner(s): Nguyen, Kevin M
• Application Number:
  US14/581,683
• Publication Number:
  US 20160179226A1
• Time in Patent Office: 1,477 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 3/03545 Pens or stylus
• CPC Class Codes: G06F 3/04162 for exchanging data with external devices, e.g. smart pens, via the digitiser sensing hardware
• 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 3/0442 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
• 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: G09G 3/20 for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters

Abstract

In an example, a processing system for an integrated display and capacitive sensing device includes a sensor module and a determination module. The sensor module includes sensor circuitry configured to be coupled to a plurality of sensor electrodes. The sensor module is configured to receive an active pen signal with at least one sensor electrode of the plurality the sensor electrodes. The determination module is configured to adjust a sensing period of the sensor module for alignment with a transmission period of the active pen signal.

Claims

1. A processing system for an integrated display and capacitive sensing device, comprising:

a sensor module including sensor circuitry configured to be coupled to a plurality of sensor electrodes, the sensor module configured to receive an active pen signal with at least one sensor electrode of the plurality of sensor electrodes; and

a determination module configured to adjust a blanking period for the integrated display for alignment with a transmission period of the active pen signal in response to receiving the active pen signal.

2. The processing system of claim 1, wherein the sensor module is further configured to detect presence of an active pen based on the received active pen signal.

3. The processing system of claim 1, wherein the at least one sensor electrode comprises a grid electrode disposed between at least two sensor electrodes of the plurality of sensor electrodes.

4. The processing system of claim 3, wherein the grid electrode comprises a plurality of segments, and wherein the sensor module is configured to receive the active pen signal with the at least one sensor electrode by receiving the active pen signal with at least two segments of the plurality of segments.

5. The processing system of claim 1, wherein the sensor module is further configured to receive the active pen signal by measuring current supplied to maintain the at least one sensor electrode at a target voltage.

6. The processing system of claim 1, wherein the plurality of sensor electrodes comprises a grid electrode, and wherein the at least one sensor electrode comprises at least two sensor electrodes circumscribed by the grid electrode and wherein the sensor module is configured to receive the active pen signal concurrently with the at least two sensor electrodes.

7. The processing system of claim 1, wherein the plurality of sensor electrodes comprise at least one electrode used to update the display and at least one electrode not used to update the display, and wherein the at least one sensor electrode comprises the at least one electrode not used to update the display.

8. The processing system of claim 1, wherein the sensor module is configured to receive the active pen signal during a display update period.

9. The processing system of claim 1, wherein the sensor module is configured to receive the active pen signal by measuring current supplied to maintain the at least one sensor electrode at a target voltage while capacitive sensing using sensor electrodes in the plurality of sensor electrodes other than the at least one sensor electrode.

21. The processing system of claim 1, wherein the blanking period is between display update periods of a display frame.

22. The processing system of claim 1, wherein the determination module is configured to adjust the blanking period by adjusting a phase difference between the active pen transmission period and the blanking period.

10. An input device integrated with a display, the input device comprising:

a plurality of sensor electrodes; and

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

receive an active pen signal with at least one sensor electrode of the plurality of sensor electrodes; and

adjust a blanking period for the display for alignment with a transmission period of the active pen signal in response to receiving the active pen signal.

11. The input device of claim 10, wherein the processing system is further configured to detect presence of an active pen based on the received active pen signal.

12. The input device of claim 10, wherein the at least one sensor electrode comprises a grid electrode disposed between at least two sensor electrodes of the plurality of sensor electrodes.

13. The input device of claim 12, wherein the grid electrode comprises a plurality of segments, and wherein the processing system is configured to receive the active pen signal with at least two segments of the plurality of segments.

14. The input device of claim 11, wherein the processing system is further configured to receive the active pen signal by measuring current supplied to maintain the at least one sensor electrode at a target voltage.

15. The input device of claim 10, wherein the plurality of sensor electrodes comprises a grid electrode, wherein the at least one sensor electrode comprises at least two sensor electrodes circumscribed by the grid electrode, and wherein the processing system is configured to receive the active pen signal concurrently with the at least two sensor electrodes.

16. The input device of claim 11, wherein the plurality of sensor electrodes comprises at least one electrode used to update the display and at least one electrode not used to update the display, and wherein the at least one sensor electrode comprises the at least one electrode not used to update the display.

17. The input device of claim 11, wherein the processing system is configured to receive the active pen signal during a display update period.

18. A method of operating an input device integrated with a display, the method comprising:

receiving an active pen signal with at least one sensor electrode of a plurality of sensor electrodes; and

adjusting a blanking period for the display for alignment with a transmission period of the active pen signal in response to receiving the active pen signal.

19. The method of claim 18, wherein the plurality of sensor electrodes comprises at least one electrode used to update the display and at least one electrode not used to update the display, and wherein the at least one sensor electrode comprises the at least one electrode not used to update the display.

20. The method of claim 18, wherein the active pen signal is received during a display update period.

23. The method of claim 18, wherein the blanking period is between display update periods of a display frame.

24. The method of claim 18, wherein the step of adjusting the blanking period comprises adjusting a phase difference between the active pen transmission period and the blanking period.