Optical routing elements

• US 6,785,039 B2
• Filed: 06/03/2002
• Issued: 08/31/2004
• Est. Priority Date: 06/03/2002
• Status: Expired due to Fees

• Current Assignee: Altera Corporation (Intel Corporation)
• Original Assignee: PTS Corporation
• Inventors: Wendland, Ronald G. Jr.
• Primary Examiner(s): Epps, Georgia
• Assistant Examiner(s): HASAN, MOHAMMED A
• Application Number:
  US10/161,838
• Publication Number:
  US 20030223677A1
• Time in Patent Office: 820 Days
• Field of Search: 359/223, 359/290, 359/291, 359/298, 359/295, 359/292, 359/225, 359/229, 359/224, 345/84, 345/85
• US Class Current: 359/290
• CPC Class Codes: G02B 6/3518 the reflective optical element being an intrinsic part of a MEMS device, i.e. fabricated together with the MEMS device MEMS devices in general B81B; manufacture of MEM devices in general B81C; micromechanical devices controlling the direction of light G02B26/0833
• CPC Class Codes: G02B 6/356 in an optical cross-connect device, e.g. routing and switching aspects of interconnecting different paths propagating different wavelengths to (re)configure the various input and output links switching polarized beams G02B6/3594; power equalizers G02B6/356 and G02B6/3594; path selecting means H04Q11/0001
• CPC Class Codes: G02B 6/357 Electrostatic force electrostatic forces controlling reflecting elements in general G02B26/0841
• CPC Class Codes: G02B 6/3584 constructional details of an associated actuator having a MEMS construction, i.e. constructed using semiconductor technology such as etching MEMS per se B81B, B81C

Abstract

The present invention provides improved MEMS devices and methods for use with fiber-optic communications systems. In one embodiment, an apparatus (100) for steering light has a base layer (110), a beam layer (114) and a folded flexure assembly (120) coupled therebetween. The folded flexure assembly complete underlies the beam layer, and facilitates rotation of the beam layer relative to the base layer. The flexure assemblies further provide a counter rotation force to help prevent the beam layer from sticking in an actuated position. In one aspect, the base layer includes raised portions (140, 142) which operate as mechanical stops for the beam layer. In this manner, the counter rotation force helps prevent the beam layer from sticking to the base layer or the raised portions.

Claims

1. An apparatus for steering light, comprising:

a base layer;

a folded flexure assembly coupled to said base layer and completely underlying a beam layer;

said beam layer overlying and coupled to said folded flexure assembly, said beam layer adapted to rotate relative to said base layer; and

wherein said folded flexure further comprises;

a first arm coupled to said base layer; and

a second arm coupled to said beam layer;

wherein said first and second arms are coupled together, with said coupled portion of said first and second arms disposed between said beam layer and said base layer.

2. The apparatus as in claim 1 wherein said base layer further comprises first and second electrically conductive portions that are physically and electrically isolated from each other.

3. The apparatus as in claim 2 wherein said first electrically conductive portion is coupled to a voltage source, said beam layer adapted to rotate when a voltage is applied to said first electrically conductive portion.

4. The apparatus as in claim 1 wherein said beam layer comprises a substantially planar upper surface adapted to reflect electromagnetic energy.

5. The apparatus as in claim 1 wherein said first and second arms are substantially parallel to each other when said beam layer is in a non-rotated state.

6. The apparatus as in claim 1 wherein said first and second arms are in a non-parallel alignment when said beam layer is in a rotated state.

7. The apparatus as in claim 1 wherein said folded flexure assembly further comprises a second pair of said first and second arms.

8. The apparatus as in claim 1 wherein said beam layer comprises an electrically conductive material.

9. The apparatus as in claim 1 wherein the beam layer is adapted to rotate about an axis of rotation, and wherein the coupled portion of the first and second arms is disposed on a first side of the axis of rotation.

10. The apparatus as in claim 9 wherein the first arm is coupled to the base layer and the second arm is coupled to the beam layer on a second side of the axis of rotation.

11. An apparatus for steering light, comprising:

a base layer;

a folded flexure assembly coupled to said base layer and completely underlying a beam layer;

said beam layer overlying and coupled to said folded flexure assembly, said beam layer adapted to rotate relative to said base layer; and

further comprising spaced apart first and second raised portions coupled to said base layer, said beam layer adapted to contact said first raised portion when rotated in a first direction and adapted to contact said second raised portion when rotated in a second direction.

12. The apparatus as in claim 11 wherein said first and second raised portions each extend substantially a full width of said base layer.

13. The apparatus as in claim 11 wherein said first and second raised portions are positioned to define the maximum angle of rotation in said first direction and in said second direction, respectively.

14. The apparatus as in claim 11 wherein said folded flexure assembly is adapted to provide a restoring force to said beam layer when said beam layer is in a rotated state, said restoring force of sufficient strength to prevent said beam layer from sticking to said first and second raised portions.

15. An apparatus for steering light, comprising:

a base layer;

a folded flexure assembly coupled to said base layer and completely underlying a beam layer;

said beam layer overlying and coupled to said folded flexure assembly, said beam layer adapted to rotate relative to said base layer; and

wherein said folded flexure assembly is adapted to provide a restoring force to said beam layer when said beam layer is in a rotated state.

16. The apparatus as in claim 15 wherein said restoring force is of sufficient strength to prevent said beam layer from sticking to said base layer.

17. An apparatus for steering light, comprising:

a base layer;

a folded flexure assembly coupled to said base layer and completely underlying a beam layer;

said beam layer overlying and coupled to said folded flexure assembly, said beam layer adapted to rotate relative to said base layer; and

wherein said beam layer has a non-rotated state and a rotated state defining an angle therebetween, said angle ranging between about ±

1 degree and about ±

30 degrees.

18. An apparatus for steering light, comprising:

a base layer comprising an electrode;

a reflective layer;

a flexure assembly coupled to and between said base layer and said reflective layer;

wherein said reflective layer rotates relative to said base layer; and

wherein said flexure assembly comprises;

a first arm coupled to said base layer; and

a second arm coupled to said beam layer;

wherein said first and second arms are coupled together, with said coupled portion of said first and second arms disposed between said beam layer and said base layer;

wherein said flexure assembly is adapted to permit an electrode-induced rotation of said beam layer when a voltage is applied to said electrode, said flexure assembly further providing a counter-rotation force generally opposite said electrode-induced rotation.

19. The apparatus as in claim 18 wherein said counter-rotation force prevents said beam layer from remaining in a rotated state when said voltage is removed.

20. An apparatus for steering light, comprising:

a base layer;

a flexure assembly coupled to said base layer; and

a beam layer overlying and coupled to said flexure assembly, said beam layer adapted to rotate relative to said base layer;

wherein said flexure assembly is adapted to impart a counter rotation force when said beam layer rotates.

21. The apparatus as in claim 20 further comprising a conductive layer overlying a portion of said base layer, said conductive layer having first and second portions that are physically and electrically isolated.

22. The apparatus as in claim 20 wherein said beam layer comprises a substantially planar upper surface adapted to reflect electromagnetic energy.

23. The apparatus as in claim 20 wherein said beam layer rotates about an axis of rotation, and said flexure assembly further comprises:

a first arm coupled to said base layer on a first side of said axis of rotation and coupled to said beam layer on a second side of said axis of rotation; and

a second arm coupled to said base layer on said second side of said axis of rotation and coupled to said beam layer on said first side of said axis of rotation.

24. The apparatus as in claim 23 wherein said arms are substantially parallel to each other when said beam layer is in a non-rotated state.

25. The apparatus as in claim 23 wherein said flexure assembly further comprises a second pair of said first and second arms.

26. The apparatus as in claim 20 wherein said conductive layer first portion is coupled to a voltage source, said beam layer adapted to rotate when a voltage is applied to said conductive layer first portion.

27. The apparatus as in claim 20 wherein said beam layer comprises an electrically conductive material.

28. The apparatus as in claim 20 wherein said beam layer has a non-rotated state and a rotated state defining an angle therebetween, said angle ranging between about one (1) degree and about thirty (30) degrees.

29. The apparatus as in claim 20 wherein said flexure assembly is entirely underlying said beam layer.

30. The apparatus as in claim 20 wherein the beam layer rotates about an axis of rotation, and the flexure assembly further comprises:

a first arm coupled to the base layer on a first side of the axis of rotation; and

a second arm coupled to the beam layer on the first side of the axis of rotation;

wherein the first and second arms are coupled together, the coupled portion disposed on a second side of the axis of rotation.

31. An apparatus for steering light, comprising:

a base layer;

first and second spaced apart electrodes overlying said base layer;

a flexure assembly coupled to said base layer;

a beam layer coupled to said flexure assembly and overlying said electrodes;

wherein said flexure assembly is adapted to permit an electrode-induced rotation of said beam layer when a voltage is applied to one of said electrodes, said flexure assembly further providing a counter-rotation force generally opposite said electrode-induced rotation; and

wherein said counter-rotation force prevents said beam layer from remaining in a rotated state when said voltage is removed,

wherein said counter-rotation force prevents said beam layer from remaining in a rotated state when said voltage is removed.

32. An apparatus for steering light, comprising:

a base layer;

first and second spaced apart electrodes overlying said base layer;

a flexure assembly coupled to said base layer;

a beam layer coupled to said flexure assembly and overlying said electrodes;

wherein said flexure assembly is adapted to permit an electrode-induced rotation of said beam layer when a voltage is applied to one of said electrodes, said flexure assembly further providing a counter-rotation force generally opposite said electrode-induced rotation; and

wherein said flexure assembly comprises first and second arms coupled to said base layer and said beam layer.

33. The apparatus as in claim 32 wherein said beam layer rotates about an axis of rotation, and wherein:

said first arm is coupled to said base layer on a first side of said axis of rotation and coupled to said beam layer on a second side of said axis of rotation; and

said second arm is coupled to said base layer on said second side of said axis of rotation and coupled to said beam layer on said first side of said axis of rotation.

34. A structure for steering light, comprising:

a base;

an electrode overlying said base;

a flexure assembly; and

a reflective layer coupled to said flexure assembly;

wherein said flexure assembly is adapted to permit said reflective layer to move into a rotated state when a voltage is applied to said electrode, said rotated state having a portion of said reflective layer contacting said base, and said flexure assembly further preventing said reflective layer from remaining in said rotated state when said voltage is removed.

35. The structure as in claim 34 wherein said flexure assembly comprises first and second arms, said arms being generally parallel to each other when said reflective layer is in a non-rotated state.

36. The structure as in claim 34 wherein said flexure assembly comprises first and second arms, said arms defining a generally X-shaped configuration when said reflective layer is in said rotated state.

37. The structure as in claim 34 wherein said reflective layer rotates about an axis of rotation, said flexure assembly further comprising:

a first arm coupled to said base on a first side of said axis of rotation and coupled to said reflective layer on a second side of said axis of rotation; and

a second arm coupled to said base on said second side of said axis of rotation and coupled to said reflective layer on said first side of said axis of rotation.