Noise reduction in a digitizer system

• US 9,823,774 B2
• Filed: 02/23/2016
• Issued: 11/21/2017
• Est. Priority Date: 02/23/2016
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Inventors: Winebrand, Amil
• Primary Examiner(s): NGUYEN, JENNIFER T
• Application Number:
  US15/050,656
• Publication Number:
  US 20170242520A1
• Time in Patent Office: 637 Days
• Field of Search: 345174, 345179, 178 1806
• CPC Class Codes: G06F 1/1626 with a single-body enclosure integrating a flat display, e.g. Personal Digital Assistants [PDAs]
• CPC Class Codes: G06F 1/1643 the display being associated to a digitizer, e.g. laptops that can be used as penpads details related to the relative motion of the display enclosure with respect to the body enclosure, e.g. to move between laptop and tablet PC configuration G06F1/1615
• CPC Class Codes: G06F 1/1656 Details related to functional adaptations of the enclosure, e.g. to provide protection against EMI, shock, water, or to host detachable peripherals like a mouse or removable expansions units like PCMCIA cards, or to provide access to internal components for maintenance or to removable storage supports like CDs or DVDs, or to mechanically mount accessories mounting of accessories to a computer display G06F1/1607; display hoods G06F1/1603; cooling arrangements for portable computers G06F1/203
• CPC Class Codes: G06F 1/1688 the I/O peripheral being integrated loudspeakers
• CPC Class Codes: G06F 2203/04104 Multi-touch detection in digitiser, i.e. details about the simultaneous detection of a plurality of touching locations, e.g. multiple fingers or pen and finger
• CPC Class Codes: G06F 3/03545 Pens or stylus
• CPC Class Codes: G06F 3/0383 Signal control means within the pointing device
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/16 Sound input; Sound output speech processing G10L

Abstract

A method includes detecting a first signal on first electrodes along a first axis of a digitizer sensor, detecting a second signal on second electrodes along a second axis of the digitizer sensor, determining that hand input exists over the first electrodes based at least on the first signal and no hand input exists over the second electrodes. A first phase of the first signal detected on the second electrodes is determined. A second phase of the second signal detected on the first electrodes is estimated based on the first phase and a portion of the first signal associated with the second phase is extracted. Coordinates of a handheld device is determined based on the portion of the first signal extracted from the first electrodes and the second signal and the coordinates are reported to a host computing device associated with the digitizer sensor.

Claims

1. A method comprising:

detecting a first signal on first electrodes along a first axis of a digitizer sensor;

detecting a second signal on second electrodes along a second axis of the digitizer sensor;

determining that hand input exists over the first electrodes based at least on the first signal;

determining that no hand input exists over the second electrodes;

determining a first phase of the second signal detected on the second electrodes;

estimating a second phase of the second signal detected on the first electrodes based on the first phase;

extracting a portion of the first signal associated with the second phase;

determining coordinates of a handheld device based on the portion of the first signal extracted from the first electrodes and the second signal; and

reporting the coordinates to a host computing device associated with the digitizer sensor.

2. The method of claim 1, wherein the first signal detected on the first electrodes and the second signal detected on the second electrodes are based on a radiated signal transmitted by the handheld device.

3. The method of claim 2, comprising estimating location of the handheld device based on the first signal and the second signal and estimating the second phase based on the location estimated.

4. The method of claim 3, wherein the estimating of the second phase based on the location estimated is based on empirical data.

5. The method of claim 2, comprising removing noise from the first signal based on characterization of the hand input in a frequency range of the signal transmitted by the handheld device.

6. The method of claim 1, wherein the hand input is detected based on a mutual capacitive detection method.

7. The method of claim 1, wherein the hand input is detected based on a self capacitive detection method.

8. The method of claim 1, wherein amplitude of the output is adjusted based on the extracting.

9. The method of claim 1, comprising decoding information embedded in at least one of the first and second signal and reporting the information to the host computing device.

10. A device comprising:

a digitizer sensor including electrodes extending along a first axis and a second axis of the digitizer sensor, wherein the electrodes are configured to pick up signals emitted by a handheld device and to sense presence of a hand with capacitive based detection;

a circuit configured to;

detect device first signal on first electrodes along the first axis and a second signal on second electrodes along the second axis;

determine that hand input exists over the first electrodes based at least on the first signal;

determine that no hand input exists over the second electrodes;

determine a first phase of the second signal detected on the second electrodes;

estimate a second phase of the second signal detected on the first electrodes based on the first phase;

extract a portion of an output on the first electrodes associated with the second phase;

determine coordinates of a handheld device based on the portion of the output extracted from the first electrodes and the second signal; and

report the coordinates to a host computing device associated with the digitizer sensor.

11. The device of claim 10, wherein the first signal detected on the first electrodes and the second signal detected on the second electrodes are based on a radiated signal transmitted by the handheld device.

12. The device of claim 11, wherein the circuit is configured to estimate location of the handheld device based on the first signal and the second signal and estimating the second phase based on the location estimated.

13. The device of claim 11, wherein the estimating of the second phase based on the location estimated is based on empirical data.

14. The device of claim 11, wherein the circuit is configured to remove noise from the first signal based on characterization of the hand input in a frequency range of the signal transmitted by the handheld device.

15. The device of claim 10, wherein the hand input is detected based on a mutual capacitive detection method.

16. The device of claim 10, wherein the hand input is detected based on a self capacitive detection method.

17. The device of claim 10, wherein amplitude of the output is adjusted based on the extracting.

18. The device of claim 10, wherein the circuit is configured to decode information embedded at least one of the first and second signal and reporting the information to the host computing device.

19. A method comprising:

detecting a first signal on first electrodes along a first axis of a digitizer sensor;

detecting a second signal on second electrodes along a second axis of the digitizer sensor, wherein the first signal detected on the first electrodes and the second signal detected on the second electrodes are based on a radiated signal transmitted by a handheld device;

determining that hand input exists over the first electrodes based at least on the first signal;

determining that no hand input exists over the second electrodes;

removing noise from the first signal based on characterization of the hand input in a frequency range of the signal transmitted by the handheld device;

determining a first phase of the second signal detected on the second electrodes;

estimating a second phase of the second signal detected on the first electrodes based on the first phase;

further removing noise in the first signal by extracting a portion of the first signal associated with the second phase, wherein the extracting is performed on the first signal after removing the noise based characterization of the hand input in a frequency range; and

determining coordinates of a handheld device based on the portion of the output extracted from the first electrodes and the second signal; and

reporting the coordinates to a host computing device associated with the digitizer sensor.

20. The method of claim 19, comprising estimating location of the handheld device based on the first signal and the second signal and estimating the second phase based on the location estimated.