Variable blazed grating

• US 20050099692A1
• Filed: 11/19/2004
• Published: 05/12/2005
• Est. Priority Date: 02/02/2001
• Status: Active Grant

• Current Assignee: Cheetah Omni LLC
• Original Assignee: Cheetah Omni Incorporated A Texas Limited Liability Company
• Inventors: Islam, Mohammed N., Kuditcher, Amos
• Granted Patent: US 6,972,886 B2
• Time in Patent Office: Days
• US Class Current: 359/573
• CPC Class Codes: G02B 26/0808 by means of one or more diffracting elements
• CPC Class Codes: G02B 6/12009 comprising arrayed waveguide grating [AWG] devices, i.e. with a phased array of waveguides
• CPC Class Codes: G02B 6/2932 comprising a directional router, e.g. directional coupler, circulator
• CPC Class Codes: G02B 6/29322 Diffractive elements of the tunable type G02B6/02195 takes precedence; optical modulation devices based on a change of the optical properties of the medium G02F1/00
• CPC Class Codes: Y10S 359/90 Methods

Abstract

In one aspect of the invention, an apparatus operable to provide optical signal processing includes an inner conductive layer including an at least substantially conductive material and a plurality of at least partially reflective mirror strips disposed outwardly from the inner conductive layer and operable to receive an input optical signal, wherein none of the plurality of strips has a width greater than 40 microns. At least some of the strips are operable to undergo a partial rotation in response to a control signal, the partial rotation resulting in a diffraction of the input optical signal wherein a majority of the diffracted input signal is communicated in one direction.

Claims

1. A light processing system, comprising:

an optical tap operable to receive an unmodulated optical signal and to separate the unmodulated optical signal into a first signal part and a second signal part;

a light pipe operable to communicate at least the first signal part for processing;

an optical signal separator operable to receive at least the first signal part and to direct a portion of the first signal part for modulation;

an array of optical signal processing devices located on one or more semiconductor substrates, the array of optical signal processing devices operable to receive at least some of the portion of the first signal part and to modulate that portion of the first signal part based at least in part on a control signal received from a controller; and

an optical reflector operable to receive at least some of the modulated first signal part and to communicate the at least some of the modulated first signal part to an output;

wherein at least some of the optical signal processing devices comprise;

an inner conductive layer comprising an at least substantially conductive material and a plurality of electrically coupled first conductors; and

a plurality of at least partially reflective mirrors disposed outwardly from the inner conductive layer and operable to receive at least some of the first signal part, wherein none of the plurality of mirrors has a width greater than 40 microns and wherein at least some of the mirrors are operable to undergo a partial rotation in response to the control signal, the partial rotation resulting in a reflection of the at least some of the first signal part wherein a majority of the reflected first signal part is communicated in one direction;

wherein each of the plurality of electrically coupled first conductors is associated with a separate one of at least some of the plurality of at least partially reflective mirrors and disposed approximately inwardly from a first edge of the associated mirror;

wherein each of the plurality of electrically coupled first conductors is coupled to the same drive source; and

wherein the control signal comprises a voltage operable to create one of a plurality of selectable non-zero voltage differentials between the inner conductive layer and at least the first edges of the associated mirrors to create a force tending to rotate the first edges of the mirrors toward the associated first conductor resulting in one of a plurality of selectable angles of rotation of the mirrors.

2. The light processing system of claim 1, wherein the unmodulated optical signal comprises a multiple wavelength optical signal and wherein at least some of the wavelengths comprise a different center wavelength.

3. The light processing system of claim 1, wherein the optical tap comprises a fiber optic tap.

4. The light processing system of claim 1, wherein the first signal part and the second signal part are substantially similar copies.

5. The light processing system of claim 1, wherein the first signal part and the second signal part comprise unequal quantities of wavelengths.

6. The light processing system of claim 1, wherein the optical tap is a reflective surface that reflects at least some of the unmodulated optical signal.

7. The light processing system of claim 1, wherein the light pipe comprises a delay line.

8. The light processing system of claim 1, wherein the light pipe comprises a single-mode optical fiber.

9. The light processing system of claim 1, wherein the first signal part communicated by the light pipe comprises a bandwidth of 100 nm or more.

10. The light processing system of claim 1, wherein the optical signal separator is selected from the group consisting of a beam splitter, a fiber optic tap, a demultiplexer, and a circulator.

11. The light processing system of claim 1, wherein the optical signal separator comprises a wavelength division demultiplexer that separates the first signal part into a plurality of optical signals, each optical signal carrying one or more wavelengths of light.

12. The light processing system of claim 1, wherein the mirrors are operable to undergo a maximum rotation that is greater than 2 degrees.

13. The light processing system of claim 1, wherein the one or more semiconductor substrates comprise silicon.

14. The light processing system of claim 1, wherein the controller is located on one of the one or more semiconductor substrates.

15. The light processing system of claim 1, wherein the optical reflector is selected from the group consisting of a reflective surface, a mirror, and a wavelength division multiplexer.

16. The light processing system of claim 1, wherein the optical reflector receives the at least some of the modulated first signal part from a first direction and communicates the at least some of the modulated first signal part to the output in a second direction.

17. The light processing system of claim 16, wherein an angle between the first direction and the second direction is less than ninety (90) degrees.

18. The light processing system of claim 1, wherein the optical reflector is a substantially flat mirror.

19. The light processing system of claim 1, wherein the optical reflector receives the majority of the reflected first signal part when the majority of the reflected first signal part is communicated in the one direction and communicates the majority of the reflected first signal part to the output, and wherein the optical reflector does not receive the majority of the reflected first signal part when the majority of the reflected first signal part is communicated in another direction.

20. The light processing system of claim 1, further comprising a collecting device to multiplex at least a portion of the modulated first signal part with other modulated signal parts into a multiple wavelength output signal.

21. A light processing system operable to receive and process one or more optical signals, the light processing system comprising:

an optical tap operable to receive an optical signal and to separate the optical signal into a first signal part and a second signal part;

a light pipe operable to communicate at least the first signal part of the optical signal for processing;

an optical signal separator operable to receive at least the first signal part and to direct a portion of the first signal part for processing;

an array of optical signal processing devices located on one or more semiconductor substrates, the array of optical signal processing devices operable to perform an optical signal processing operation on at least the portion of the first signal part;

an electronic processor coupled to the array of optical signal processing devices, the electronic processor operable to perform a processing operation on at least some of the portion of the first signal part; and

an optical reflector operable to receive at least some of the processed first signal part and to direct the at least some of the processed first signal part to an output;

wherein at least some of the optical signal processing devices comprise;

an inner conductive layer comprising an at least substantially conductive material and a plurality of electrically coupled first conductors; and

a plurality of at least partially reflective mirrors disposed outwardly from the inner conductive layer and operable to receive at least some of the first signal part, wherein none of the plurality of mirrors has a width greater than 40 microns and wherein at least some of the mirrors are operable to undergo a partial rotation in response to one or more control signals, the partial rotation resulting in a reflection of the at least some of the portion of the optical signal wherein a majority of the reflected optical signal is communicated in one direction;

wherein each of the plurality of electrically coupled first conductors is associated with a separate one of at least some of the plurality of at least partially reflective mirrors and disposed approximately inwardly from a first edge of the associated mirror;

wherein each of the plurality of electrically coupled first conductors is coupled to the same drive source; and

wherein the one or more control signals comprise a voltage operable to create one of a plurality of selectable non-zero voltage differentials between the inner conductive layer and at least the first edges of the associated mirrors to create a force tending to rotate the first edges of the mirrors toward the associated first conductor resulting in one of a plurality of selectable angles of rotation of the mirrors.

22. The light processing system of claim 21, wherein the optical signal comprises a multiple wavelength optical signal and wherein at least some of the wavelengths comprise a different center wavelength.

23. The light processing system of claim 21, wherein the optical tap comprises a fiber optic tap.

24. The light processing system of claim 21, wherein the first signal part and the second signal part comprise substantially similar copies.

25. The light processing system of claim 21, wherein the first signal part and the second signal part comprise unequal quantities of wavelengths.

26. The light processing system of claim 21, wherein the tap is a reflective surface that reflects at least some of the optical signal.

27. The light processing system of claim 21, wherein the light pipe comprises a delay line.

28. The light processing system of claim 21, wherein the light pipe comprises a single-mode optical fiber.

29. The light processing system of claim 21, wherein the first signal part communicated by the light pipe comprises a bandwidth of 100 nm or more.

30. The light processing system of claim 21, wherein the optical signal separator is selected from the group consisting of a beam splitter, a fiber optic tap, a demultiplexer, and a circulator.

31. The light processing system of claim 21, wherein the optical signal separator is a wavelength division demultiplexer that separates the optical signal into a plurality of wavelength signals, each wavelength signal carrying one or more wavelengths of light.

32. The light processing system of claim 21, wherein the mirrors are operable to undergo a maximum rotation that is greater than 2 degrees.

33. The light processing system of claim 21, wherein the one or more semiconductor substrates comprise silicon.

34. The light processing system of claim 21, wherein the optical signal processing operation performed on the one or more optical signals is selected from the group consisting of variable attenuation, optical switching, and add/drop multiplexing.

35. The light processing system of claim 21, wherein the optical reflector is selected from the group consisting of a reflective surface, a mirror, and a wavelength division multiplexer.

36. The light processing system of claim 21, wherein the optical reflector receives the at least some of the processed first signal part from a first direction and communicates the at least some of the processed first signal part to the output in a second direction.

37. The light processing system of claim 36, wherein an angle between the first direction and the second direction is less than ninety (90) degrees.

38. The light processing system of claim 21, wherein the optical reflector comprises a substantially flat mirror.

39. The light processing system of claim 21, wherein the optical reflector receives the majority of the reflected first signal part when the majority of the reflected first signal part is communicated in the one direction and communicates the majority of the reflected first signal part to the output, and wherein the optical reflector does not receive the majority of the reflected first signal part when the majority of the reflected first signal part is communicated in another direction.

40. The light processing system of claim 21, further comprising a collecting device to multiplex at least a portion of the modulated first signal part with other modulated signal parts into a multiple wavelength output signal.

41. A method of processing one or more optical signals, the method comprising:

separating an optical signal into a first signal part and a second signal part;

communicating at least the first signal part of the optical signal for processing;

separating the first signal part into at least a first portion and a second portion;

receiving at least the first portion of the first signal part at an array of optical signal processing devices, the array of optical signal processing devices located on one or more semiconductor substrates and comprising a plurality of at least partially reflective mirrors disposed outwardly from an inner conductive layer, the inner conductive layer comprising an at least substantially conductive material and a plurality of electrically coupled first conductors, wherein none of the plurality of mirrors has a width greater than 40 microns;

performing an optical signal processing operation on at least the first portion of the first signal part, the optical signal processing operation comprising;

receiving at least some of the first portion of the first signal part at the at least partially reflective mirrors;

rotating at least some of the mirrors in response to one or more control signals, the partial rotation resulting in a reflection of the at least some of the portion of the optical signal wherein a majority of the reflected optical signal is communicated in one direction, wherein rotating at least one of the plurality of mirror strips comprises applying one of a plurality of selectable non-zero voltage differentials between the inner conductive layer and at least a first edge of the associated mirror to create a force tending to rotate the first edge of the associated mirror toward the associated first conductor resulting in one of a plurality of selectable angles of rotation of the associated mirror;

wherein each of the plurality of electrically coupled first conductors is associated with a separate one of at least some of the plurality of at least partially reflective mirrors and disposed approximately inwardly from the first edge of the associated mirror;

wherein each of the plurality of electrically coupled first conductors is coupled to the same drive source; and

communicating at least some of the processed first portion of the first signal part to an output.

42. The method of claim 41, wherein the optical signal comprises a multiple wavelength optical signal and wherein at least some of the wavelengths comprise a different center wavelength.

43. The method of claim 41, wherein the first signal part and the second signal part comprise substantially similar copies.

44. The method of claim 41, wherein the first signal part and the second signal part comprise unequal quantities of wavelengths.

45. The method of claim 41, wherein the at least partially reflective mirrors are operable to undergo a maximum rotation that is greater than 2 degrees.

46. The method of claim 41, wherein the optical signal processing operation performed on the one or more optical signals is selected from the group consisting of variable attenuation, optical switching, add/drop multiplexing, and modulating the first portion of the first signal part.