DIGITIZER SYSTEM

• US 20130234961A1
• Filed: 03/06/2013
• Published: 09/12/2013
• Est. Priority Date: 03/06/2012
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: N-Trig Ltd (Microsoft Corporation)
• Inventors: Mann, Eytan, Gershfeld, Arthur, GARFINKEL, Gadi, Nahear, Shimon
• Granted Patent: US 9,690,395 B2
• Time in Patent Office: Days
• US Class Current: 345/173
• 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 3/0418 for error correction or compensation, e.g. based on parallax, calibration or alignment
• CPC Class Codes: G06F 3/0441 using active external devices, e.g. active pens, for receiving changes in electrical potential transmitted by the digitiser, e.g. tablet driving signals
• 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: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes

Abstract

A digitizer system includes a designated sensing area comprising a plurality of sensing lines for sensing an electromagnetic signal emitted by a stylus interacting with the digitizer system, circuitry for detecting output from the plurality of sensing lines and for determining an interacting position of the stylus in the designated sensing area based on the output detected and a peripheral area contiguous to the designated sensing area. The peripheral area includes a plurality of conductive elements for connecting the plurality of sensing lines to the circuitry and at least one auxiliary sensing line extending over the peripheral area in the vicinity of the plurality of conductive elements and connected to the circuitry. The at least one auxiliary sensing line is operable to sense the electromagnetic signal when it is emitted over the peripheral area and the circuitry is operable to detect output from the at least one auxiliary sensing line.

Claims

1. A digitizer system comprising:

a designated sensing area comprising a plurality of sensing lines for sensing an electromagnetic signal emitted by a stylus interacting with the digitizer system;

circuitry for detecting output from the plurality of sensing lines and for determining an interacting position of the stylus in the designated sensing area based on the output detected; and

a peripheral area contiguous to the designated sensing area, the peripheral area comprising;

a plurality of conductive elements for connecting the plurality of sensing lines to the circuitry; and

at least one auxiliary sensing line extending over the peripheral area in the vicinity of the plurality of conductive elements and connected to the circuitry;

wherein the at least one auxiliary sensing line is operable to sense the electromagnetic signal when it is emitted over the peripheral area; and

wherein the circuitry is operable to detect output from the at least one auxiliary sensing line.

2. The digitizer system of claim 1, wherein the circuitry is operative to identify when the electromagnetic signal is emitted over the peripheral area outside the designated sensing area, in response to the output detected on the at least one auxiliary sensing line.

3. The digitizer system of claim 1, wherein the at least one auxiliary sensing line and the plurality of conductive elements are patterned on a same surface.

4. The digitizer system of claim 1, wherein the at least one auxiliary sensing line and the plurality of conductive elements are patterned on different layers.

5. The digitizer system of claim 1, wherein the at least one auxiliary sensing line is formed from a same material as the sensing lines in the designated sensing area.

6. The digitizer system of claim 1, wherein the auxiliary sensing line is substantially parallel to a side of the designated sensing area.

7. The digitizer system of claim 1, wherein the peripheral area extends near two contiguous edges of the designated sensing area, and wherein the at least one auxiliary sensing area extends substantially parallel to the two contiguous edges of the designated sensing area.

8. The digitizer system of claim 1, wherein the at least one auxiliary sensing line is formed from a same material as the conductive elements for connecting each of the plurality of sensing lines to the circuitry.

9. The digitizer system of claim 1, wherein the at least one auxiliary sensing line is formed from at least one of:

silver, Molybdenum, indium tin oxide, indium-doped zinc oxide, a conductive polymer, carbon nano-tube, metal nano-particles, metal, and antimony tin oxide.

10. The digitizer system of claim 1, wherein a first set of the plurality of sensing lines and a first auxiliary sensing line of the at least one auxiliary sensing line is patterned on a first layer and a second set of the plurality of sensing lines and a second auxiliary sensing line of the at least one auxiliary sensing line is patterned on a second layer, the second layer superimposed on the first layer.

11. A method for determining an interacting position of a stylus with digitizer system, the method comprising:

detecting a stylus signal received in a designated sensing area of a digitizer sensor;

detecting a stylus signal received in a peripheral area contiguous to the designated sensing area, wherein the contiguous area includes a plurality of conductive elements for connecting the digitizer sensor to circuitry of the digitizer system; and

determining the validity of the stylus signal received in the designated sensing area based on the input from the stylus in the area contiguous to the designated sensing area.

12. The method according to claim 11, comprising only reporting the interaction position of the stylus in the designated sensing area in response to determining that the input from this stylus is valid.

13. The method according to claim 11, comprising:

determining amplitude of the input from the stylus in the designated sensing area;

determining amplitude of the input from the stylus in the peripheral area; and

determining the validity of the input from the stylus in the designated sensing area based on a ratio between the amplitude in the designated sensing area and the amplitude in the peripheral area.

14. The method according to claim 11, comprising:

determining a spread of the input from the stylus in the designated sensing area; and

determining the validity of the input from the stylus in the designated sensing area based on the spread of the input.