Dual axis micro-machined mirror device

• US 20020012180A1
• Filed: 06/01/2001
• Published: 01/31/2002
• Est. Priority Date: 07/13/1999
• Status: Active Grant

• Current Assignee: Input/Output Incorporated
• Original Assignee: Input/Output Incorporated
• Inventors: Schmidt, Martin, Yu, Duli, Yu, Lianzhong, Goldberg, Howard
• Granted Patent: US 6,454,421 B2
• Time in Patent Office: Days
• US Class Current: 359/872
• CPC Class Codes: G02B 26/0841 the reflecting element being moved or deformed by electrostatic means
• CPC Class Codes: G02B 7/1821 for rotating or oscillating mirrors

Abstract

A micro machined mirror assembly is provided that includes a micro machined top cap, mirror, and bottom cap mounted onto a ceramic substrate. The micro machined mirror is resiliently supported by a pair of T-shaped hinges. At least two electrostatic force application pads are disposed to rotate the mirror about a primary axis and about a secondary axis.

Claims

1. An apparatus for supporting a mass, comprising;

(a) a mass having having a first axis and a second axis of rotation;

(b) a pair of T-shaped hinges attached to a support structure supporting said mass, each T-shaped hinge having a first leg member attached to the mass and a T-member attached to the leg and to the support structure at opposite ends of the T-member, said T-member and leg member capable of torsional and translational movement;

(c) at least two devices operatively associated with the mass and located to apply force to the mass, the force capable of rotating the mass about the first and second axes,

wherein the T-shaped hinges allow for the mass vertical movement, movement along a first planar direction and movement along a second planar direction, wherein said vertical, first and second planar directions are orthogonal to each other.

2. The apparatus of claim 1, wherein the mass further comprises a reflective surface.

3. The apparatus of claim 1 further comprising at least one x-travel stop limiting movement of the mass in the first planar direction.

4. The apparatus of claim 3, wherein the at least one x-travel stop includes a first member carried by the support structure and a second member carried by the mass.

5. The apparatus of claim 4, wherein the mass has a plurality of sides and wherein the at least one x-travel stop includes a separate travel stop corresponding to each said side of the mass.

6. The apparatus of claim 3 further comprising at least one y-travel stop limiting movement of the mass in the second planar direction.

7. The apparatus of claim 6, wherein at least one y-travel stop includes a member carried by the support structure that limits the movement of the mass in the second planar direction.

8. The apparatus of claim 6, wherein the mass has a plurality of sides and at least one y-travel stop includes a separate member carried by the support structure to limit movement of the mass along each said side of the mass.

9. The apparatus of claim 1 further comprising a first planar stop to limit movement of the mass in the first planar direction and a second planar stop to limit the movement of the mass in the second planar direction.

10. The apparatus of claim 9, wherein the first planar stop includes a first member carried by the support structure and a second member carried by the mass which cooperate with each other to limit travel of the mass in the first planar direction and the second planar stop includes a member carried by the mass that limits travel of the mass in the second planar directions.

11. The apparatus of claim 1 further comprising a vertical travel stop that limits the movement of the mass in the vertical direction that is perpendicular to the a surface of the mass.

12. The apparatus of claim 11, wherein the vertical travel stop includes a separate finger member placed a predetermined distance from each said T-shaped hinge, each said finger member having length greater than a planar dimensions of the T-shaped hinges.

13. The apparatus of claim 1, wherein each said hinge has a predetermined rotational spring constant and a translational spring constant wherein the torsional spring constant is decoupled from the translational spring constant.

14. The apparatus of claim 1, wherein the leg member is perpendicular to the T-member in one or more of the T-shaped hinges.

15. The apparatus of claim 1, wherein leg member is serpentine in one or more of the T-shaped hinges.

16. The apparatus of claim 1, wherein the leg member is offset from the center of the T-member in one or more of the T-shaped hinges.

17. The apparatus of claim 1, wherein the leg member intersects the T-member at an acute angle in one or more of the T-shaped hinges.

18. A method for supporting a mass, comprising;

(a) supporting the mass with a pair of T-shaped hinges attached to a support structure, each T-shaped hinge having a first leg member attached to the mass and a T-member attached to the leg and to the support structure at opposite ends of the T-member, said T-member and leg member capable of torsional and translational movement, wherein the T-shaped hinges allow for the mass vertical movement, movement along a first planar direction and movement along a second planar direction, wherein said vertical, first and second planar directions are orthogonal to each other; and

(b) oscillating the mass about a first axis with at least two devices capable of applying force to the mass; and

(c) oscillating the mass about a second axis with the at least two devices.

19. The method of claim 18, wherein the mass further comprises a reflective surface.

20. The method of claim 18 further comprising limiting movement of the mass in the first planar direction using at least one x-travel stop.

21. The method of claim 20, wherein the at least one x-travel stop includes a first member carried by the support structure and a second member carried by the mass.

22. The method of claim 20 further comprising limiting movement of the mass in the second planar direction using at least one y-travel stop.

23. The method of claim 22, wherein the mass has a plurality of sides and the at least one y-travel stop includes a separate member carried by the support structure, the method further comprising limiting movement of the mass along each said side of the mass using the plurality of sides and the separate member.

24. The method of claim 18, wherein the support structure further comprises a vertical travel stop, the method further comprising limiting movement of the mass in the vertical direction that is perpendicular to a surface of the mass using the vertical stop.

25. The method of claim 18, wherein the first axis is perpendicular to the second axis.