One-to-M wavelength routing element

• US 20030174958A1
• 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: Weaver, Samuel Paul, Cizek, Nicholas Charles
• Granted Patent: US 6,959,132 B2
• Time in Patent Office: Days
• US Class Current: 385/47
• CPC Class Codes: G02B 26/0816 by means of one or more reflecting elements
• CPC Class Codes: G02B 5/12 Reflex reflectors
• 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 6/3548 1xN switch, i.e. one input and a selectable single output of N possible outputs
• 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 one-to-M wavelength routing elements are provided. Each retroreflecting element is configured to retroreflect an optical ray that is orthogonal to a reference plane. A first reflective surface, such as may be provided by a mirror, is inclined with respect to the reference plane and is disposed to encounter the optical ray. The first reflective surface is also configured for rotation about an axis to multiple positions. A second reflective surface, such as may also be provided by a mirror, is inclined with respect to the first reflective surface. In at least one of the positions, the optical ray also encounters the second reflective surface.

Claims

1. An element for retroreflecting an optical ray incident orthogonal to a plane, the element comprising:

a first reflective surface inclined with respect to the plane and configured for rotation about an axis to a plurality of positions, the first reflective surface being disposed to encounter the optical ray; and

a second reflective surface inclined with respect to the first reflective surface for at least one of the plurality of positions.

2. The element recited in claim 1 wherein the first reflective surface and the second reflective surface define an included angle substantially equal to 90°

.

3. The element recited in claim 1 wherein the second reflective surface comprises a plurality of second reflective surfaces, each such second reflective surface being disposed, for the at least one of the plurality of positions, to encounter the optical ray.

4. The element recited in claim 3 wherein the axis is substantially orthogonal to the plane.

5. The element recited in claim 3 wherein each of the second reflective surfaces is inclined with respect to the plane at substantially the same angle.

6. The element recited in claim 3 wherein the first reflective surface has a circular projection on the plane.

7. The element recited in claim 3 wherein each of the plurality of second mirrors is fixed.

8. The element recited in claim 3 wherein the plurality of second reflective surfaces are arranged to define vertices of a polygon around the first reflective surface.

9. The element recited in claim 8 wherein the polygon is regular.

10. The element recited in claim 3 wherein in at least one of the plurality of positions the optical ray encounters none of the second reflective surfaces.

11. The element recited in claim 1 wherein the axis is substantially orthogonal to the plane and the second reflective surface is disposed in a fixed inclined relationship to the first reflective surface.

12. The element recited in claim 11 wherein the first and second reflective surfaces are comprised by a common structure.

13. The element recited in claim 1 wherein the second reflective surface comprises a frustoconical reflective surface disposed to surround the first reflective surface.

14. The element recited in claim 13 wherein the frustoconical reflective surface is concentric about the axis.

15. The element recited in claim 13 wherein the frustoconical reflective surface is disposed such that the optical ray is substantially focused upon encountering the if frustoconical reflective surface.

16. The element recited in claim 13 wherein the frustoconical reflective surface includes a gap through which the optical ray is directed in at least one of the plurality of positions.

17. The element recited in claim 13 wherein the frustoconical reflective surface includes an absorptive portion to which the optical ray is directed in at least one of the plurality of positions.

18. The element recited in claim 1 wherein the plurality of positions comprises a continuum of positions.

19. The element recited in claim 18 wherein the at least one of the plurality of positions is chosen for selective attenuation of the optical ray.

20. The element recited in claim 1 wherein the plurality of positions comprises a plurality of discrete positions.

21. A method for directing an optical ray, the method comprising:

reflecting the optical ray from a first reflective surface towards a second reflective surface, wherein both the first and second reflective surfaces are inclined with respect to a plane orthogonal to a propagation direction of the optical ray; and

rotating the first reflective surface about an axis orthogonal to the plane to one of a plurality of positions.

22. The method recited in claim 21 further comprising thereafter reflecting the optical ray from a third reflective surface.

23. The method recited in claim 21 wherein the second and third reflective surfaces are inclined with respect to the plane at substantially the same angle.

24. The method recited in claim 21 wherein the second reflective surface is disposed in a fixed inclined relationship to the first reflective surface.

25. The method recited in claim 24 wherein the first and second reflective surfaces are comprised by a common structure

26. The method recited in claim 21 wherein the second reflective surface comprises a frustoconical reflective surface disposed to surround the first reflective surface.

27. The method recited in claim 26 further comprising focusing the optical ray on the frustoconical reflective surface.

28. The method recited in claim 21 wherein the plurality of positions comprises a continuum of positions.

29. The method recited in claim 28 wherein the one of the plurality of positions is chosen for selective attenuation of the optical ray.

30. The method recited in claim 21 wherein the plurality of positions comprises a plurality of discrete positions.

31. An element for retroreflecting an optical ray incident orthogonal to a plane, the element comprising:

first reflecting means inclined with respect to the plane and configured for rotation about an axis to a plurality of position, the first reflecting means being disposed to encounter the optical ray; and

second reflecting means inclined with respect to the first reflecting means for at least one of the plurality of positions.

32. The element recited in claim 31 wherein the second reflecting means comprises a plurality of reflective surface means, each such reflective surface means being disposed, for the at least one of the plurality of positions, to encounter the optical ray.

33. The element recited in claim 31 wherein the second reflecting means is disposed in a fixed inclined relationship to the first reflecting means.

34. The element recited in claim 33 wherein the first and second reflecting means are comprised by a common structural means.

35. The element recited in claim 31 wherein the second reflecting means comprises a frustoconical reflecting means disposed to surround the first reflecting means.

36. A one-to-M wavelength routing element for receiving, at an input port, light having a plurality of spectral bands, and directing selected ones of the spectral bands to one or more of M output ports, the one-to-M wavelength routing element comprising:

a free-space optical train disposed between the input port and the M 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 a plane and configured for rotation about an axis to a plurality of positions; and

a second reflective surface inclined with respect to the first reflective surface for at least one of the plurality of positions,

wherein M≧

2.

37. The wavelength routing element recited in claim 36 wherein M>

2.

38. The wavelength routing element recited in claim 36 wherein each dynamically configurable retroreflecting element includes a plurality of second reflective surfaces inclined with respect to the first reflective surface for at least one of the positions.

39. The wavelength routing element recited in claim 36 wherein the first and second reflective surfaces are comprised by a common structure such that the second reflective surface is disposed in a fixed inclined relationship to the first reflective surface.

40. The wavelength routing element recited in claim 36 wherein the second reflective surface comprises a frustoconical reflective surface disposed to surround the first reflective surface.

41. The wavelength routing element recited in claim 36 wherein, for each of the plurality of dynamically configurable retroreflecting elements, at least one of the plurality of positions causes a corresponding spectral band to be directed to none of the M output ports.

42. The wavelength routing element recited in claim 36 wherein:

the input port is at the end of an input fiber;

each of the output ports is at the end of an output fiber; and

the output fibers are disposed circumferentially about the input fiber.

43. The wavelength routing element recited in claim 36 wherein the at least one of the plurality of positions is chosen for selective attenuation of a respective spectral band.