SYSTEM AND METHOD FOR DETECTING SURFACE PERTURBATIONS

• US 20120229121A1
• Filed: 03/10/2011
• Published: 09/13/2012
• Est. Priority Date: 03/10/2011
• Status: Active Grant

• Current Assignee: Snaptrack Incorporated (Qualcomm, Inc.)
• Original Assignee: Qualcomm MEMS Technologies Incorporated (Qualcomm, Inc.)
• Inventors: Sampsell, Jeffrey B.
• Granted Patent: US 8,714,023 B2
• Time in Patent Office: Days
• US Class Current: 324/109
• CPC Class Codes: G01B 7/28 for measuring contours or curvatures

Abstract

This disclosure provides systems, methods and apparatus for assessing a surface using a piezoelectric element. In one aspect, the method includes applying a device to the surface, wherein the device includes at least one piezoelectric element and at least one EMS device, wherein the EMS device includes a conductive first layer separated from a conductive second layer, and wherein the piezoelectric element is electrically coupled to the EMS device such that a force applied to the piezoelectric element results in a voltage applied across the first and second layers.

Claims

1. A device for assessing a surface, the device comprising:

at least one piezoelectric element; and

at least one electromechanical system (EMS) device including a conductive first layer separated from a conductive second layer,

wherein the piezoelectric element is electrically coupled to the EMS device such that a force applied to the piezoelectric element results in an introduction of charge to both the first and second layers.

2. The device of claim 1, wherein the at least one piezoelectric element comprises a two-dimensional array of piezoelectric elements, wherein the at least one EMS device comprises a two-dimensional array of EMS devices, and wherein each of the piezoelectric elements is electrically coupled to a EMS device at a corresponding location.

3. The device of claim 1, wherein the at least one piezoelectric element comprises lead zirconate titanate.

4. The device of claim 1, the at least one EMS device having reflective properties that change in response to an introduction of charge to both the first and second layers.

5. The device of claim 1, wherein the at least one EMS device comprises at least one interferometric modulator.

6. The device of claim 1, wherein the first layer is at least partially reflective and at least partially transmissive and wherein the second layer is at least partially reflective.

7. The device of claim 1, wherein the piezoelectric element is electrically coupled to the EMS device via at least one conductor.

8. The device of claim 1, wherein a first surface of the piezoelectric element is electrically coupled to the first layer and wherein a second surface of the piezoelectric element is electrically coupled to the second layer.

9. The device of claim 1, further comprising a separate capacitive element, wherein a first surface of the piezoelectric element is electrically coupled to both the first layer and the second layer and a second surface of the piezoelectric element is electrically coupled to the separate capacitive element.

10. The device of claim 1, further comprising a flexible membrane and a substrate, wherein the at least one piezoelectric element is sandwiched between the flexible membrane and the substrate.

11. The device of claim 10, further comprising a housing, wherein the housing comprises a transparent window through which a user can view the at least one MEM device.

12. The device of claim 11, wherein the housing comprises a rigid portion between the flexible membrane and the substrate.

13. The device of claim 11, wherein the housing comprises a flexible portion between the flexible membrane and the substrate.

14. The device of claim 10, wherein the at least one EMS device is formed on the substrate.

15. The device of claim 10, further comprising a second substrate, wherein the at least one EMS device is formed on the second substrate.

16. The device of claim 1, further comprising one or more shunts configured to discharge accumulated charge from the piezoelectric element.

17. The device of claim 16, further comprising a user input device which, when used by a user, causes the shunts to discharge the accumulated charge.

18. The device of claim 1, further comprising an image capture device configured to image the at least one EMS device.

19. The device of claim 1, further comprising at least one of a processor or a power source.

20. A method of assessing a surface, the method comprising:

applying a device to the surface, the device comprising at least one piezoelectric element and at least one EMS device including a conductive first layer separated from a conductive second layer, wherein the piezoelectric element is electrically coupled to the EMS device such that a force applied to the piezoelectric element results in an introduction of charge to both the first and second layers.

21. The method of claim 20, further comprising:

viewing the at least one EMS device; and

determining the presence of a perturbation on the surface based on the viewing.

22. The method of claim 21, wherein viewing the at least one EMS device is performed by an image capturing device and wherein determining the presence of a perturbation on the surface is performed by a processor.

23. The method of claim 21, wherein determining the presence of a perturbation comprises:

determining that at least one EMS device at a specific location has changed appearance; and

determining the presence of a perturbation at a corresponding location of the specific location.

24. The method of claim 21, further comprising removing the perturbation from the surface.

25. The method of claim 24, further comprising repeating the method for a plurality of perturbations.

26. The method of claim 24, wherein removing the perturbation comprises machining, sanding, or laser-removing the perturbation.

27. The method of claim 20, wherein the device comprises a flexible membrane and applying the device to the surface comprises applying the flexible membrane to the surface.

28. The method of claim 20, further comprising:

applying a second device to the surface, the second device comprising at least one piezoelectric element and at least one EMS device including a conductive first layer separated from a conductive second layer, wherein the piezoelectric element is electrically coupled to the EMS device such that a force applied to the piezoelectric element results in a voltage applied across the first and second layers,

wherein the second device comprises a second flexible membrane and applying the second device to the surface comprises applying the second flexible membrane to the surface, and

wherein the flexible membrane and the second flexible membrane have different degrees of flexibility.

29. The method of claim 20, further comprising moving the device.

30. A device for assessing a surface, the device comprising:

means for generating a voltage in response to an applied force; and

means for changing reflective properties in response to an applied voltage,

wherein the means for generating is electrically coupled to the means for changing such that a force applied to the means for generating results in a voltage applied across means for changing.

31. The device of claim 30, wherein the means for generating comprises at least one piezoelectric element.

32. The device of claim 30, wherein the means for changing comprises at least one EMS device.

33. The device of claim 30, wherein the means for changing comprises at least one interferometric modulator.

34. The device of claim 30, wherein means for generating is electrically coupled to means for generating via at least one means for conducting electric current.

35. The device of claim 30, further comprising means for flexing and a means for supporting, wherein the means for generating is sandwiched between the means for flexing and the means for supporting.

36. The device of claim 30, further comprising means for housing, wherein the means for housing comprises a transparent means through which a user can view the means for changing.

37. The device of claim 30, further comprising means for discharging accumulated charge of the means for generating.

38. The device of claim 37, further comprising means for receiving user input which, when used by a user, causes the means for discharging to discharge the accumulated charge.

39. The device of claim 37, further comprises at least one of means for processing or means for providing power.