MULTI-TOUCH AND SINGLE TOUCH DETECTION

• US 20090251434A1
• Filed: 04/02/2009
• Published: 10/08/2009
• Est. Priority Date: 04/03/2008
• Status: Active Grant

• Current Assignee: Microsoft Technology Licensing LLC (Microsoft Corporation)
• Original Assignee: N-Trig Ltd (Microsoft Corporation)
• Inventors: Rimon, Ori, Perski, Haim, Zachut, Rafi, Ben-David, Amihai
• Granted Patent: US 8,289,289 B2
• Time in Patent Office: Days
• US Class Current: 345/173
• CPC Class Codes: G06F 1/30 Means for acting in the event of power-supply failure or interruption, e.g. power-supply fluctuations for resetting only G06F1/24
• 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 3/0442 using active external devices, e.g. active pens, for transmitting changes in electrical potential to be received by the digitiser
• CPC Class Codes: G06F 3/0445 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
• CPC Class Codes: G06F 3/046 by electromagnetic means

Abstract

An input device comprises a touch sensitive sensor operative to sense finger touch, a detection unit controllable to apply a single touch detection method over at least one area of the touch sensitive sensor and a multi-touch detection method over at least one other area of same touch sensitive sensor, and a controller operative to set the areas of single touch and multi-touch detection.

Claims

1. An input device comprising:

a touch sensitive sensor operative to sense finger touch;

a detection unit controllable to apply a single touch detection method over at least one area of the touch sensitive sensor and a multi-touch detection method over at least one other area of same touch sensitive sensor; and

a controller operative to set the areas of single touch and multi-touch detection.

2. The input device according to claim 1, wherein the different areas partially overlap.

3. The input device according to claim 1, wherein the controller is operative to dynamically set the areas of single touch and multi-touch detection.

4. The input device according to claim 3, wherein the at least one area is defined based on requirements of an application running on a host associated with the touch sensitive sensor.

5. The input device according to claim 1, wherein the detection unit is operative to apply the multi-touch detection method over a plurality of different areas.

6. The input device according to claim 1, wherein a refresh rate associated with the touch sensitive sensor is responsive of a size of the area where the multi-touch method is applied and wherein limiting size of the area where the multi-touch method is applied provides for increasing the refresh rate of the input device.

7. The input device according to claim 1, wherein the at least one area detected based on the multi-touch detection method is sampled at a lower resolution than the at least one area detected based on the single touch detection method.

8. The input device according to claim 1, wherein the touch sensitive sensor is formed with a plurality of conductive lines formed in a grid.

9. The input device according to claim 8, wherein at least one of the conductive lines spans at least two areas where different detection methods are applied.

10. The input device according to claim 8 wherein the single touch detection method is based on detecting a difference signal between parallel conductive lines of the grid.

11. The input device according to claim 8, wherein the detection unit is operative to simultaneously trigger and sample the conductive lines over the single touch detection area.

12. The input device according to claim 8, wherein the detection unit is operative to sequentially trigger conductive lines along one axis of the grid over the multi-touch detection area.

13. The input device according to claim 12, wherein the detection unit is operative to sample conductive lines within the multi-touch detection area in response to each trigger.

14. The input device according to claim 8, wherein the controller is operative to provide for sampling output from a same conductive line over a first period based on the single touch detection method and over a second period based on the multi-touch detection method.

15. The input device according to claim 14, wherein the detection unit is operative to switch to an alternate circuit path during the second sampling period.

16. The input device according to claim 8, wherein the controller is operative to provide for sampling every other conductive line in a multi-touch detection area over a first sampling cycle and to sample all lines not sampled in the first sampling cycle during a subsequent sampling cycle.

17. The input device according to claim 1, wherein during a single sampling cycle, the controller is operative to provide for first sampling the touch sensitive sensor based on the single touch detection method and subsequently sampling an area applied for multi-touch detection based on the multi-touch detection method.

18. The input device according to claim 1, wherein the touch sensitive sensor provides for detecting stylus input in at least one of the detection areas.

19. The input device according to claim 18, wherein the input device provides for sampling touch and stylus signals on the conductive lines substantially simultaneously.

20. The input device according to claim 1, wherein the different detection methods are associated with different triggering or interrogation frequencies.

21. The input device according to claim 20, wherein the single touch and multi-touch areas area are sampled substantially simultaneously.

22. A method for touch detection, the method comprising:

controllably setting at least one multi-touch detection area on a touch sensitive sensor for applying multi-touch detection;

applying multi-touch detection only in the defined at least one multi-touch detection area;

applying single touch detection in at least areas of the touch sensitive screen other than the at least one multi-touch detection area; and

detecting touch over each of the defined areas.

23. The method according to claim 22, wherein the at least one multi-touch detection area and the areas where single touch detection is applied, partially overlap.

24. The method according to claim 22, wherein the setting is performed dynamically.

25. The method according to claim 22, wherein the touch sensitive sensor is formed with conductive lines formed in a grid.

26. The method according to claim 25, wherein in the areas where the single touch detection is applied, the conductive lines are triggered and sampled substantially simultaneously.

27. The method according to claim 25, wherein in the at least one multi-touch detection area, conductive lines along one axis of the grid are triggered in sequence and in response to each triggering, conductive lines in a cross axis are sampled.

28. The method according to claim 22, comprising detecting stylus input in the at least one multi-touch detection area.

29. The method according to claim 28, wherein stylus output signals and finger touch output signals area detected substantially simultaneously in the at least one multi-touch detection area.

30. The method according to claim 22, comprising sampling the at least one area where single touch detection is applied over a first sampling period and subsequently sampling the at least one multi-touch detection area over a second sampling period, wherein the first and second sampling period are included in a single sampling cycle.

31. The method according to claim 22, comprising sampling output from the at least one multi-touch detection area at a lower resolution as compared to sampled output in the areas where single touch detection is applied.

32. An input device comprising:

a touch sensitive sensor operative to sense finger touch;

a detection unit controllable to apply a first touch detection method over at least one area of the touch sensitive sensor and a second detection method over at least one other area of same touch sensitive sensor; and

a controller operative to set the areas of the first touch and second detection method.

33. The input device according to claim 32, wherein the different areas partially overlap.

34. The input device according to claim 32, wherein at least one of the areas is dynamically defined.

35. The input device according to claim 32, wherein during a single sampling cycle, the controller is operative to sample at least a portion of the touch sensitive sensor based on the first touch detection method and subsequently sample at least another portion of the touch sensitive sensor based on the second touch detection method.