Electrostatic device

• US 20040056742A1
• Filed: 09/23/2003
• Published: 03/25/2004
• Est. Priority Date: 12/11/2000
• Status: Active Grant

• Current Assignee: Rad H. Dabbaj
• Original Assignee: Rad H. Dabbaj
• Inventors: Dabbaj, Rad H.
• Granted Patent: US 7,196,599 B2
• Time in Patent Office: Days
• US Class Current: 335/78
• CPC Class Codes: H01G 5/18 due to change in inclination, e.g. by flexing, by spiral wrapping
• CPC Class Codes: H02N 1/006 of the gap-closing type H02N1/004 takes precedence

Abstract

An electrostatic device (10) includes a first flexible electrode (1) on which a plurality of second electrodes (2) are mounted so as to move with the first electrode (1). Upon the application of an electrical charge, the or each second electrode (2) causes deflection of the first electrode (1) which deflection is enhanced by the movement of the second electrode therewith. A variety of different designs of the device are possible to provide movement of the first electrode in a plurality of directions and also different types of in and out of plane movement, including rotation and twisting. The structure enables the device to operate at voltage levels compatible with integrated circuits and for the device to be manufactured using integrated circuit manufacturing techniques.

Claims

1. An electrostatic device including a first flexible electrode able to be deflected, and at least one second electrode mounted on the first electrode so as to move therewith and to cause deflection of the first electrode upon the application of an electrical charge to the electrodes.

2. A device according to claim 1, wherein the device is mounted on a support.

3. A device according to claim 1 or 2, wherein there is provided a plurality of second electrodes located proximate one another on the first electrode.

4. A device according to claim 3, wherein the or at least some of the second electrodes are arranged in a linear array.

5. A device according to claim 3 or 4, wherein the or at least some of the second electrodes are arranged in a non-linear array.

6. A device according to claim 3, 4 or 5, wherein the second electrodes are arranged to produce deflections of the first electrode about more than one axis.

7. A device according to any preceding claim, including a plurality of first electrodes, each first electrode being provided with at least one second electrode mounted thereon.

8. A device according to claim 7, wherein the first electrodes are coupled together mechanically such that deflection of one first electrode affects the position of the or at least one other first electrode.

9. A device according to claim 8, wherein the first electrodes are arranged serially, in parallel, in different planes or at an angle to one another or in any combination of these.

10. A device according to any preceding claim, wherein the device is capable of movement out of and/or in its own plane.

11. A device according to claim 10, wherein deflection causes contraction of the device in one or two directions.

12. A device according to any preceding claim, including a plurality of second electrodes arranged on the first electrode or electrodes in a manner as to provide deflection of the first electrode or electrodes in opposing directions.

13. A device according to claim 12, wherein one or more second electrodes are located on a first surface of the first electrode or electrodes and one or more second electrodes are located on an opposing second surface of the first electrode or electrodes.

14. A device according to any preceding claim, wherein the or each second electrode is stiffer that the first electrode on which it is mounted.

15. A device according to any preceding claim, wherein when a plurality of second electrodes is provided, at least two adjacent second electrodes overlap.

16. A device according to claim 15, wherein said at least two second electrodes are provided with fingers extending substantially in a plane thereof and which interdigitate with one another.

17. A device according to any preceding claim, wherein there is provided a common supply rail for supplying the first and second electrodes with power.

18. A device according to any preceding claim, wherein there is provided a plurality of supply rails for supplying the first and/or second electrodes in different manners.

19. A device according to claim 17 or 18, including a control unit operable to control electrical power applied to the first and second electrodes.

20. A device according to any preceding claim, wherein the second electrode or electrodes are mounted on the first electrode in bridge manner and/or in cantilever manner.

21. A device according to any preceding claim, wherein the first and/or second electrodes are layered members including at least one conductive layer.

22. A device according to any preceding claim, wherein the first electrode or electrodes have apertures, weakness or strengthening areas to adjust the deflection properties thereof.

23. A device according to any one of claims 1 to 21, wherein the or each first electrode is impervious.

24. A device according to any preceding claim, wherein a gap between the first and second electrodes is kept under a vacuum or filled with one or more of a gas, liquid, gel or deformable solid material.

25. A device according to any preceding claim wherein at least one second electrode is used as a part of an actuator and at least one second electrode is used as part of a sensor.

26. A device according to any preceding claim, wherein the device is used both as an actuator and a sensor on a time-sharing basis.

29. A mirror assembly including an electrostatic device according to any preceding claim.

30. A speaker, earphone, microphone, ultrasonic detector or transducer assembly including an electrostatic device according to any one of claims 1 to 28.

31. An optical scanner, beam steering or all-optical-switch assembly including an electrostatic device according to any one of claims 1 to 28.

32. A pressure sensor, pump or inkjet cartridge assembly including an electrostatic device according to any one of claims 1 to 28.

33. An accelerometer or sensor assembly including an electrostatic device according to any one of claims 1 to 28.

34. A one, two or three dimensional array of two or more electrostatic devices according to any preceding claim.

27. An electrostatic device including first and second electrodes arranged in first and second planes respectively, both of which electrodes are operable to move in a direction at an angle to the plane thereof on application of an electrical charge.

28. An electrostatic device produced by an integrated circuit fabrication, a MEMS fabrication or a microfabrication process.