Closed-loop sensor on a solid-state object position detector

• US 20050156881A1
• Filed: 02/16/2005
• Published: 07/21/2005
• Est. Priority Date: 04/11/2002
• Status: Active Grant

• Current Assignee: Wacom Co Limited (Wacom)
• Original Assignee: Synaptics Incorporated
• Inventors: Gillespie, David W., Shaw, Scott J., Trent, Raymond A. Jr., Huie, Mark A., Heiny, Christopher
• Granted Patent: US 8,259,076 B2
• Time in Patent Office: Days
• US Class Current: 345/157
• CPC Class Codes: G06F 2203/0339 Touch strips, e.g. orthogonal touch strips to control cursor movement or scrolling; single touch strip to adjust parameter or to implement a row of soft keys
• CPC Class Codes: G06F 3/03547 Touch pads, in which fingers can move on a surface
• CPC Class Codes: G06F 3/0448 Details of the electrode shape, e.g. for enhancing the detection of touches, for generating specific electric field shapes, for enhancing display quality

Abstract

The present disclosure discloses an object position detector. The object position detector comprises a touch sensor formed as a closed loop and having a physical constraint formed on an upper surface of the touch sensor and coextensive with the closed loop. The touch sensor is configured to sense motion of an object proximate to the closed loop. The object position detector also comprises a processor coupled to the touch sensor and is programmed to generate an action in response to the motion on the touch sensor.

Claims

1. A solid-state object position detector for indicating a desired user interface navigation task, comprising:

a touch sensor having a plurality of electrodes disposed in a substantially closed loop, said touch sensor configured to sense an object proximate to said substantially closed loop; and

a processor coupled to said touch sensor, said processor configured to provide relative motion information about said object moving proximate to said substantially closed loop, said relative motion information representative of a difference between a first position and second position of said object, said relative motion information indicating said desired user interface navigation task.

2. The solid-state object position detector of claim 1, wherein said touch sensor comprises a capacitive touch sensor.

3. The solid-state object position detector of claim 1, wherein said processor is configured to provide said relative motion information in one coordinate.

4. The solid-state object position detector of claim 1, further comprising at least one activation zone disposed proximate to said touch sensor and coupled to said processor, said activation zone configured to indicate a second user interface task.

5. The solid-state object position detector of claim 1, wherein said touch sensor includes a first starting position along said substantially closed loop and a second starting position along said substantially closed loop, and wherein said processor is further configured to cause a first action responsive to sensing motion of said object starting proximate to said first starting position and configured to cause a second action responsive to sensing motion of said object starting proximate to said second starting position.

6. The solid-state object position detector of claim 1, wherein said desired user interface navigation task comprises scrolling.

7. The solid-state object position detector of claim 1, wherein at least two of said plurality of electrodes are self-interpolating and configured to provide radial position information about said object moving proximate to said substantially closed loop.

8. The solid-state object position detector of claim 7, wherein the plurality of electrodes are configured such that a first subset of the plurality of electrodes are wider toward an outer edge of the touch sensor and a second subset of the plurality of electrodes are wider toward an inner edge of the touch sensor and wherein the first subset and second subset of the plurality of electrodes alternate along the substantially closed loop.

9. The solid-state object position detector of claim 7, wherein radial position information about said object moving proximate said substantially closed loop is determined by a comparison of capacitance in the first subset of the plurality of electrodes and the second subset of the plurality of electrodes.

10. The solid-state object position detector of claim 1, wherein at least two of said plurality of electrodes are coupled to a single sensor input.

11. The solid-state object position detector of claim 1, wherein the processor is further configured to provide absolute position information about said object moving proximate to said substantially closed loop.

12. The solid-state object position detector of claim 1, wherein at least one of said plurality of electrodes is interdigitated with an adjacent one of said plurality of electrodes.

13. The solid-state object position detector of claim 12, wherein more than one interdigitation occurs between each adjacent electrode in the plurality of electrodes.

14. The solid-state object position detector of claim 12, wherein a layout of the plurality of electrodes comprises a lighting bolt layout.

15. The solid-state object position detector of claim 1, further comprising a second touch sensor having a second plurality of electrodes, said touch sensor and said second touch sensor sharing sensor inputs.

16. The solid-state object position detector of claim 15, wherein said touch sensor further comprises an indicator electrode, the indicator electrode disposed proximate to said plurality of electrodes, and wherein the indicator electrode is configured to indicate said object moving proximate to said substantially closed loop.

17. The solid-state object position detector of claim 15, wherein said second plurality of electrodes includes a first subset of electrodes for a first axis, and a second subset of electrodes for a second axis, and wherein the first plurality of electrodes share said sensor inputs with said first subset of electrodes for the first axis.

18. The solid-state object position detector of claim 15, wherein said second plurality of electrodes is disposed in a second substantially closed loop.

19. The solid-state object position detector of claim 1, wherein the processor is configured to provide relative motion information about said object moving proximate to said substantially closed loop by determining which of the plurality of electrodes has a largest capacitance measurement, fitting capacitance measurements of selected electrodes having capacitance measurement to an inverted parabola, and calculating a center point of the inverted parabola.

20. The solid-state object position detector of claim 19, wherein the processor is further configured to reduce the center point by a modulo N and passing the center point through a non-linear function to compensate for non-linearities.

21. The solid-state object position detector of claim 1, further comprising a pointing stick disposed at a center of said substantially closed loop.

22. The solid-state object position detector of claim 21, wherein the pointing stick is configured to operate as a pointing device and wherein the touch sensor is configured to operate as a scrolling device.

23. The solid-state object position detector of claim 22, further comprising at least one touch sensitive zone proximate said touch sensor, said touch sensitive zone configured to emulate a button.

24. A solid-state object position detector, comprising:

a touch sensor having a plurality of electrodes disposed in a substantially closed loop, said touch sensor configured to sense an object proximate to said substantially closed loop; and

a processor coupled to said touch sensor, said processor configured to provide positional information about said object proximate to said substantially closed loop in only one coordinate.

25. The solid-state object position detector of claim 24, wherein said processor provides said one coordinate to control scrolling in a user interface.

26. The solid-state object position detector of claim 24, wherein said touch sensor includes a first starting position along said substantially closed loop and a second starting position along said substantially closed loop, and wherein said processor is further configured to cause a first action responsive to sensing motion of said object starting proximate to said first starting position and configured to cause a second action responsive to sensing motion of said object starting proximate to said second starting position.

27. A solid-state object position detector, comprising:

a touch sensor having a plurality of electrodes disposed in a substantially closed loop, said touch sensor configured to sense an object proximate to said substantially closed loop, said plurality of electrodes configured such that adjacent electrodes are interdigitated such that capacitance introduced by the object is measured by a subset of the plurality of electrodes; and

a processor coupled to said touch sensor, said processor configured to provide positional information about said object proximate to said substantially closed loop.

28. The solid-state object position detector of claim 27, wherein more than one interdigitation occurs between each adjacent electrode in the plurality of electrodes.

29. The solid-state object position detector of claim 27, wherein a layout of the plurality of electrodes comprises a lighting bolt layout.

30. The solid-state object position detector of claim 27, wherein a first subset of the plurality of electrodes share a first input, wherein a second subset of the plurality of electrodes share a second input, and wherein a third subset of the plurality electrodes share a third input.