Device and method for micro-electro-mechanical-system photonic switch

Patent metadata

Field	Value
Publication number	US-9612432-B2
Application number	US-201615333930-A
Country	US
Kind code	B2
Filing date	Oct 25, 2016
Priority date	Nov 21, 2013
Publication date	Apr 4, 2017
Grant date	Apr 4, 2017

Abstract

In one embodiment, a micro-electro-mechanical-system (MEMS) photonic switch includes a first plurality of collimators including a first collimator configured to receive a first traffic optical beam having a traffic wavelength and a first control optical beam having a control wavelength, where a first focal length of the first collimators at the traffic wavelength is different than a second focal length of the first collimators at the control wavelength. The MEMS photonic switch also includes a first mirror array optically coupled to the first plurality of collimators, where the first mirror array including a first plurality of first MEMS mirrors integrated on a first substrate and a first plurality of first photodiodes integrated on the first substrate, where the photodiodes are disposed in interstitial spaces between the MEMS mirrors.

First claim

What is claimed is:

1. A method of aligning a first mirror and a second mirror of a micro-electro-mechanical system (MEMS) photonic switch, the method comprising:
receiving, by a first collimator of a first plurality of collimators, a first optical control signal having a control wavelength;
receiving, by the first collimator, a first optical traffic signal having a traffic wavelength;
reflecting, by the first mirror on a first mirror array, the first optical control signal to produce a first optical control beam;
reflecting, by the first mirror, the first optical traffic signal to produce a first optical traffic beam; and
detecting, by a first photodiode having a first location on a second mirror array, a first intensity of a first control beam spot of the first optical control beam to produce a first detected optical signal, wherein the second mirror array comprises the second mirror, and wherein a first diameter of the first control beam spot is larger than a second diameter of a first traffic beam spot of the first optical traffic beam at the second mirror array.

2. The method of claim 1 , further comprising:
receiving, by a second collimator of a second plurality of collimators, a second optical control signal;
reflecting, by the second mirror, the second optical control signal to produce a second optical control beam;
detecting, by a second photodiode of the first mirror array, a second beam spot of the second optical control beam to produce a second detected signal;
adjusting a first angle of the first mirror; and
adjusting a second angle of the second mirror.

3. The method of claim 1 , wherein the first optical control beam is coaxial with the first optical traffic beam.

4. The method of claim 1 , wherein the first diameter of the first control beam spot is larger than a third diameter of the second mirror.

5. The method of claim 4 , and wherein the second diameter of the first traffic beam spot is smaller than the third diameter of the second mirror.

6. The method of claim 5 , further comprising:
detecting, by a second photodiode having a second location on the second mirror array, a second intensity of the first control beam spot to produce a second detected optical signal;
detecting, by a third photodiode having a third location on the second mirror array, a third intensity of the first control beam spot to produce a third detected optical signal; and
triangulating a center of the first control beam spot in accordance with the first detected optical signal, the second detected optical signal, and the third detected optical signal.

7. The method of claim 6 , further comprising:
determining a correction vector in accordance with the center of the first control beam spot and a center of the second mirror; and
adjusting the first mirror in accordance with the correction vector.

8. An apparatus configured to align mirrors of a micro-electro-mechanical system (MEMS) photonic switch comprising:
a first collimator configured to receive a first optical control signal having a control wavelength, and to receive a first optical traffic signal having a traffic wavelength;
a first mirror array comprising a first mirror, the first mirror configured to reflect a first optical control signal to obtain a first optical control beam, and to reflect the first optical traffic signal to obtain a first optical traffic beam; and
a second mirror array comprising a second mirror and a first photodiode, the first photodiode having a first location on the second mirror array, the first photodiode configured to detect a first intensity of a first control beam spot of the first optical control beam to obtain a first detected optical signal, wherein the second mirror array comprises the second mirror, and wherein a first diameter of the first control beam spot is larger than a second diameter of a first traffic beam spot of the first optical traffic beam at the second mirror array.

9. The apparatus of claim 8 , further comprising:
a second collimator configured to receive a second optical control signal, wherein the second mirror is configured to reflect the second optical control signal to produce a second optical control beam;
a second photodiode of the first mirror array, the second photodiode configured to detect a second beam spot of the second optical control beam to obtain a second detected signal; and
one or more processors configured to adjust a first angle of the first mirror, and adjust a second angle of the second mirror.

10. The apparatus of claim 8 , wherein the first optical control beam is coaxial with the first optical traffic beam.

11. The apparatus of claim 8 , wherein the first diameter of the first control beam spot is larger than a third diameter of the second mirror.

12. The apparatus of claim 11 , and wherein the second diameter of the first traffic beam spot is smaller than the third diameter of the second mirror.

13. The apparatus of claim 12 , further comprising:
a second photodiode having a second location on the second mirror array, the second photodiode configured to detect a second intensity of the first control beam spot to obtain a second detected optical signal; and
a third photodiode having a third location on the second mirror array, the third photodiode configured to detect a third intensity of the first control beam spot to produce a third detected optical signal; and
one or more processors configured to triangulate a center of the first control beam spot in accordance with the first detected optical signal, the second detected optical signal, and the third detected optical signal.

14. The apparatus of claim 12 , wherein the one or more processors are further configured to determine a correction vector in accordance with the center of the first control beam spot and a center of the second mirror, and to adjust the first mirror in accordance with the correction vector.

15. An apparatus comprising:
a processor; and
a non-transitory computer readable storage medium storing programming for execution by the processor, the programming including instructions to:
receive a first optical control signal having a control wavelength at a first collimator;
receive a first optical traffic signal having a traffic wavelength at the first collimator;
reflect, via the first mirror on a first mirror array, the first optical control signal to produce a first optical control beam;
reflect, via the first mirror, the first optical traffic signal to produce a first optical traffic beam; and
detect, via a first photodiode having a first location on a second mirror array, a first intensity of a first control beam spot of the first optical control beam to produce a first detected optical signal, wherein the second mirror array comprises the second mirror, and wherein a first diameter of the first control beam spot is larger than a second diameter of a first traffic beam spot of the first optical traffic beam at the second mirror array.

16. The apparatus of claim 15 , wherein the programming further includes instructions to:
receive a second optical control signal at a second collimator of a second plurality of collimators;
reflect, via a second mirror, the second optical control signal to produce a second optical control beam;
detect, via a second photodiode of the first mirror array, a second beam spot of the second optical control beam to produce a second detected signal;
adjust a first angle of the first mirror; and
adjust a second angle of the second mirror.

17. The apparatus of claim 15 , wherein the first optical control beam is c

Assignees

• Huawei Tech Co Ltd

Inventors

• Graves Alan Frank
• Goodwill Dominic John

Classifications

• G01J2001/446

  Photodiode · CPC title

• G01J1/44

  Electric circuits {(for command of an exposure part G03B7/02)} · CPC title

• G02B6/3518 Primary

  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 title

• G01B11/272

  using photoelectric detection means · CPC title

• G02B26/0833 Primary

  the reflecting element being a micromechanical device, e.g. a MEMS mirror, DMD (G02B26/0825 takes precedence; micromechanical devices in general B81B) · CPC title