Two-by-two optical routing element using two-position mems mirrors

• US 20030174941A1
• Filed: 03/13/2002
• Published: 09/18/2003
• Est. Priority Date: 03/13/2002
• Status: Active Grant

• Current Assignee: Altera Corporation (Intel Corporation)
• Original Assignee: Network Photonics, Inc.
• Inventors: Cizek, Nicholas Charles
• Granted Patent: US 7,177,498 B2
• Time in Patent Office: Days
• US Class Current: 385/31
• CPC Class Codes: G02B 6/04 formed by bundles of fibres G02B6/24 takes precedence
• CPC Class Codes: G02B 6/266 the optical element being an attenuator
• CPC Class Codes: G02B 6/29307 components assembled in or forming a solid transparent unitary block, e.g. for facilitating component alignment
• CPC Class Codes: G02B 6/2931 Diffractive element operating in reflection
• CPC Class Codes: G02B 6/352 the reflective optical element having a shaped reflective surface, e.g. a reflective element comprising several reflective surfaces or facets that function together
• CPC Class Codes: G02B 6/3546 NxM switch, i.e. a regular array of switches elements of matrix type constellation
• 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 6/3568 characterised by the actuating force
• CPC Class Codes: G02B 6/357 Electrostatic force electrostatic forces controlling reflecting elements in general G02B26/0841

Abstract

Retroreflecting elements adapted for use in two-by-two optical routing elements. Each retroreflecting element is configured to selectively retroreflect two optical rays. A first reflective surface, such as may be provided by a mirror, is inclined with respect to a reference plane. A second reflective surface, such as may also be provided by a mirror, is opposed to and inclined with respect to the first reflective surface. The two surfaces are configured for rotation about an axis to multiple positions such that in a first position, a first ray is retroreflected along a first path and second ray is reflected along a second path, and in a second position, the first ray is reflected along the second path and the second ray is reflected along the first path.

Claims

1. A device for selectively retroreflecting two input rays, the device, comprising:

a first reflective surface inclined with respect to a plane; and

a second reflective surface opposed to the first surface, thereby forming an included angle α

;

wherein the two surfaces are configured for rotation together about an axis to a plurality of positions, including at least a first position and a second position, and wherein the surfaces are disposed such that when the surfaces are in the first position, a first ray is retroreflected along a first path, and when the surfaces are in the second position, the first ray is retroreflected along a second path.

2. The device recited in claim 1 wherein the surfaces are further disposed such that when the surfaces are in the first position, a second ray is retroreflected along the second path, and when the surfaces are in the second position, the second ray is retroreflected along the first path.

3. The device recited in claim 1 wherein the first and second surfaces are formed on a common mass.

4. The device recited in claim 1 wherein α

is substantially equal to 90°

.

5. The device recited in claim 1 wherein at least one of the reflective surfaces has optical power.

6. The device recited in claim 2 wherein the paths are parallel.

7. The device recited in claim 2 wherein at least one of the paths is parallel to the axis.

8. The device recited in claim 2 wherein the surfaces are disposed in the first position for the first ray to encounter the first reflective surface before the first ray encounters the second reflective surface, and for the second ray to encounter the second reflective surface before the second ray encounters the first reflective surface.

9. The device recited in claim 8 wherein the surfaces are disposed in the second position for the first ray to encounter the second reflective surface before the first ray encounters the first reflective surface, and for the second ray to encounter the first reflective surface before the second ray encounters the second reflective surface.

10. The device recited in claim 9 wherein the one of the rays retroreflected along the first path in either the first or second positions encounters the second reflective surface after it encounters the first reflective surface.

11. The device recited in claim 10 wherein the one of the rays retroreflected along the second path in either the first or second positions encounters the first reflective surface after it encounters the second reflective surface.

12. The device recited in claim 9 wherein the one of the rays retroreflected along the second path last encounters the same one of the first or second reflecting surfaces in the second position that the ray encounters in the first position.

13. The device recited in claim 12 wherein the one of the rays retroreflected along the first path last encounters the same one of the first or second reflecting surfaces in the second position that the ray encounters in the first position.

14. The device recited in claim 8 wherein the first and second reflective surfaces are disposed in the second position for the first ray to encounter the first reflective surface before the first ray encounters the second reflective surface, and for the second ray to encounter the second reflective surface before the second ray encounters the first reflective surface.

15. The device recited in claim 14 wherein the one of the rays retroreflected along the second path last encounters a different one of the first or second reflecting surfaces in the second position than the ray encounters in the first position.

16. The device recited in claim 15 wherein the one of the rays retroreflected along the first path last encounters a different one of the first or second reflecting surfaces in the second position than the ray encounters in the first position.

17. The device recited in claim 2 wherein the device has a circular projection on the plane.

18. The device recited in claim 1 wherein the axis is substantially perpendicular to the plane.

19. The device recited in claim 1 wherein the surfaces are configured for rotation to at least a third position wherein at least one of the rays is retroreflected along a path not coincident with either the first or second paths.

20. The device recited in claim 1 wherein the plurality of positions comprises a continuum of positions.

21. The device recited in claim 20 wherein the second position is chosen for selective attenuation of the first ray.

22. The device recited in claim 1 wherein the plurality of positions comprises a plurality of discrete positions.

23. A two-by-two optical routing element for receiving, at each of a pair of input ports, light having a plurality of spectral bands, and directing selected ones of the spectral bands to either of two output ports, the two-by-two optical routing element, comprising:

a free-space optical train disposed between the input ports and the output ports providing optical paths for routing the spectral bands, the optical train having a dispersive element disposed to intercept the light traveling from the input port; and

a routing mechanism having a plurality of dynamically configurable retroreflecting elements, each such dynamically configurable retroreflecting element including;

a first reflective surface inclined with respect to an axis; and

a second reflective surface opposed to the first surface, thereby forming an included angle α

;

wherein the two surfaces are configured for rotation together about the axis to a plurality of positions including at least a first position and a second position.

24. The two-by-two optical routing element recited in claim 23 wherein the surfaces are disposed such that when the surfaces are in the first position, a first ray is retroreflected along a first path, and when the surfaces are in the second position, the first ray is retroreflected along a second path.

25. The two-by-two optical routing element recited in claim 24 wherein the surfaces are further disposed such that when the surfaces are in the first position, a second ray is retroreflected along the second path, and when the surfaces are in the second position, the second ray is retroreflected along the first path.

26. The two-by-two optical routing element recited in claim 23 wherein the surfaces are formed on a common mass.

27. The two-by-two optical routing element recited in claim 23 wherein α

is substantially equal to 90°

.

28. The two-by-two optical routing element recited in claim 23, wherein at least one of the reflective surfaces has optical power.

29. The two-by-two optical routing element recited in claim 25 wherein the paths are parallel.

30. The two-by-two optical routing element recited in claim 25 wherein at least one of the path s is parallel to the axis.

31. The two-by-two optical routing element recited in claim 23 wherein the routing mechanism has a circular projection a plane.

32. The two-by-two optical routing element recited in claim 25 wherein the surfaces are configured for rotation to at least a third position wherein at least one of the rays is retroreflected along a path not coincident with either the first or second paths.

33. The two-by-two optical routing element recited in claim 23 wherein the plurality of positions comprises a continuum of positions.

34. The two-by-two optical routing element recited in claim 33 wherein the second position is chosen for selective attenuation of the first ray.

35. The two-by-two optical routing element recited in claim 23 wherein the plurality of positions comprises a plurality of discrete positions.

36. A method for directing optical rays, comprising:

reflecting a first optical ray from a first reflective surface inclined with respect to an axis;

thereafter reflecting the first optical ray from a second reflective surface along a first optical path, the second reflective surface being opposed to the first surface thereby forming an included angle α

, wherein the two surfaces are configured for rotation together about the axis to a plurality of position;

reflecting a second optical ray from the second reflective surface; and

thereafter reflecting the second optical ray from the first reflective surface along a second optical path.

37. The method recited in claim 36 further comprising rotating the surfaces to a position such that the first ray is reflected along the second path and the second ray is reflected along the first path.

38. The method recited in claim 36 wherein the surfaces are formed on a common mass.

39. The method recited in claim 36 wherein α

is substantially equal to 90°

.

40. The method recited in claim 37 wherein the position is chosen for selective attenuation of at least one of the rays.

41. The method recited in claim 37 further comprising rotating the surfaces to a third position wherein at least one of the rays is reflected along a path not coincident with either the first or second paths.

42. The method recited in claim 36 wherein the plurality of positions comprises a continuum of positions.

43. The method recited in claim 36 wherein the plurality of positions comprises a plurality of discrete positions.

44. A device for selectively retroreflecting two input rays, the device, comprising:

first reflective means inclined with respect to a plane; and

second reflective means opposed to the first reflective means, thereby forming an included angle α

;

wherein the first and second reflective means are configured for rotation together about an axis to a plurality of positions, including at least a first position and a second position, and wherein the first and second reflective means are disposed such that when the first and second reflective means are in the first position, a first ray is retroreflected along a first path, and when the surfaces are in the second position, the first ray is retroreflected along a second path.

45. The device recited in claim 44 wherein the first and second surfaces are formed on a common mass.

46. The device recited in claim 44 wherein α

is substantially equal to 90°

.