Micro-mirror device including dielectrophoretic microemulsion

• US 20050152017A1
• Filed: 12/23/2003
• Published: 07/14/2005
• Est. Priority Date: 04/30/2002
• Status: Active Grant

• Current Assignee: Taiwan Semiconductor Manufacturing Company Limited
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Reboa, Paul F.
• Granted Patent: US 7,023,603 B2
• Time in Patent Office: Days
• US Class Current: 359/251
• CPC Class Codes: G02B 26/004 based on a displacement or a deformation of a fluid
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means

Abstract

A micro-mirror device includes a substrate having a surface, and a plate spaced from and oriented substantially parallel to the surface of the substrate such that the plate and the surface of the substrate define a cavity therebetween. A dielectrophoretic microemulsion capable of movement when an electrical signal is applied to the micro-mirror device is disposed in the cavity, and a reflective element is interposed between the surface of the substrate and the plate such that the reflective element is adapted to move between a first position and at least one second position. The dielectrophoretic microemulsion has a continuous oil phase.

Claims

1. A micro-mirror device, comprising:

a substrate having a surface;

a plate spaced from and oriented substantially parallel to the surface of the substrate, the plate and the surface of the substrate defining a cavity therebetween;

a dielectrophoretic microemulsion disposed in the cavity, the dielectrophoretic microemulsion being capable of movement when an electrical signal is applied to the device, the dielectrophoretic microemulsion having at least a continuous oil phase; and

a reflective element interposed between the surface of the substrate and the plate,

wherein the reflective element is adapted to move between a first position and at least one second position

2. A micro-mirror device according to claim 1, wherein the dielectrophoretic microemulsion comprises a polar component, a non-polar component, and an amphipathic component.

3. A micro-mirror device according to claim 1, wherein the dielectrophoretic microemulsion is compressible.

4. A micro-mirror device according to claim 1, wherein the dielectrophoretic microemulsion is thermodynamically stable and substantially transparent.

5. A micro-mirror device according to claim 1, wherein the dielectrophoretic microemulsion comprises at least one surfactant.

6. A micro-mirror device according to claim 5, wherein the dielectrophoretic microemulsion comprises an anionic surfactant.

7. A micro-mirror device according to claim 6, wherein the anionic surfactant is 1,4-Bis(2-ethylhexyl)sulfosuccinate sodium salt.

8. A micro-mirror device according to claim 6, wherein the dielectrophoretic microemulsion includes no more than about 5 percent water.

9. A micro-mirror device according to claim 1, wherein the dielectrophoretic microemulsion has a particle size of less than about 100 nanometers.

10. A micro-mirror device according to claim 1, wherein the dielectrophoretic microemulsion includes at least one oil component.

11. A micro-mirror device according to claim 10, wherein the oil component comprises from about 30 percent to about 95 percent of the dielectrophoretic microemulsion.

12. A micro-mirror device according to claim 1, wherein the dielectrophoretic microemulsion is a bi-continuous microemulsion.

13. A micro-mirror device according to claim 1, wherein the reflective element is at least one of positioned above the dielectrophoretic microemulsion and submerged in the dielectrophoretic microemulsion.

14. A micro-mirror device according to claim 1, further comprising:

at least one electrode formed on the surface of the substrate, the electrode having differing dimensions from the reflective element,

wherein the reflective element is adapted to move in response to application of an electrical signal to the at least one electrode and the electrical signal is adapted to form a non-uniform electric field in the cavity.

15. A micro-mirror device according to claim 1, wherein the dielectrophoretic microemulsion is adapted to increase an actuation force on the reflective element as generated by a given activation energy.

16. A display device including the micro-mirror device of claim 1.

17. A micro-actuator, comprising:

a substrate having a surface;

a plate spaced from and oriented substantially parallel to the surface of the substrate, the plate and the surface of the substrate defining a cavity there between;

a dielectrophoretic microemulsion disposed in the cavity and capable of movement when an electrical signal is applied to the micro-actuator, the dielectrophoretic microemulsion having a continuous oil phase; and

an actuating element interposed between the surface of the substrate and the plate,

wherein the actuating element is adapted to move between a first position and at least one second position.

18. A micro-actuator according to claim 17, wherein the dielectrophoretic microemulsion is thermodynamically stable and substantially transparent.

19. A micro-actuator according to claim 17, wherein the dielectrophoretic microemulsion comprises at least one surfactant.

20. A micro-actuator according to claim 19, wherein the dielectrophoretic microemulsion comprises an anionic surfactant.

21. A micro-actuator according to claim 20, wherein the anionic surfactant is 1,4-Bis(2-ethylhexyl)sulfosuccinate sodium salt.

22. A micro-actuator according to claim 17, wherein the dielectrophoretic microemulsion includes no more than about 5 percent water.

23. A micro-actuator according to claim 17, wherein the dielectrophoretic microemulsion has a particle size of less than about 100 nanometers.

24. A micro-actuator according to claim 17, wherein the dielectrophoretic microemulsion includes at least one oil component.

25. A micro-actuator according to claim 24, wherein the oil component comprises from about 30 percent to about 95 percent of the dielectrophoretic microemulsion

26. A micro-actuator according to claim 17, wherein the dielectrophoretic microemulsion is a bi-continuous microemulsion.

27. A micro-actuator according to claim 17, Wherein the actuating element is at least one of positioned above the dielectrophoretic microemulsion and submerged in the dielectrophoretic microemulsion.

28. A micro-actuator according to claim 17, further comprising:

at least one electrode formed on the surface of the substrate, the electrode having differing dimensions from the actuating element,

wherein the actuating element is adapted to move in response to application of an electrical signal to the at least one electrode and the electrical signal is adapted to form a non-uniform electric field in the cavity.

29. A micro-actuator according to claim 17, wherein the dielectrophoretic microemulsion is adapted to increase an actuation force on the actuating element as generated by a given activation energy.

30. A method of using a dielectrophoretic microemulsion in a micro-actuator including an actuator element adapted to move between a first position and at least one second position, the method comprising:

disposing the dielectrophoretic microemulsion in a cavity of the micro-actuator, including at least one of positioning the actuator element above and submerging the actuator element in the dielectrophoretic microemulsion; and

moving the actuator element between the first position and the least one second position, including applying an electrical signal to the micro-actuator,

wherein the dielectrophoretic microemulsion has a continuous oil phase, and

wherein the dielectrophoretic microemulsion exhibits movement when the electrical signal is applied to the micro-actuator and the movement contributes to the moving of the actuator element between the first position and the at least one second position.

31. A method of using a dielectrophoretic microemulsion according to claim 30, wherein the dielectrophoretic microemulsion is thermodynamically stable and substantially transparent.

32. A method of using a dielectrophoretic microemulsion according to claim 30, wherein the dielectrophoretic microemulsion comprises at least one surfactant.

33. A method of using a dielectrophoretic microemulsion according to claim 30, wherein the dielectrophoretic microemulsion comprises an anionic surfactant.

34. A method of using a dielectrophoretic microemulsion according to claim 33, wherein the anionic surfactant is 1,4Bis(2-ethylhexyl)sulfosuccinate sodium salt

35. A method of using a dielectrophoretic microemulsion according to claim 30, wherein the dielectrophoretic microemulsion includes no more than about 5 percent water.

36. A method of using a dielectrophoretic microemulsion according to claim 30, wherein the dielectrophoretic microemulsion has a particle size of less than about 100 nanometers.

37. A method of using a dielectrophoretic microemulsion according to claim 30, wherein the dielectrophoretic microemulsion includes at least one oil component.

38. A method of using a dielectrophoretic microemulsion according to claim 37, wherein the oil component comprises from about 30 percent to about 95 percent of the dielectrophoretic microemulsion.

39. A method of using a dielectrophoretic microemulsion according to claim 30, wherein the dielectrophoretic microemulsion is a bi-continuous microemulsion.

40. A method of using a dielectrophoretic microemulsion according to claim 30, wherein the dielectrophoretic microemulsion has a viscosity of about 0.5 centipoises to about 50 centipoises.