Fiber-attached optical devices with in-plane micromachined mirrors

• US 20040076366A1
• Filed: 10/18/2002
• Published: 04/22/2004
• Est. Priority Date: 10/18/2002
• Status: Active Grant

• Current Assignee: Analog Devices, Inc.
• Original Assignee: Analog Devices, Inc.
• Inventors: Harney, Kieran P., Judy, Michael W., Martin, John R., Felton, Lawrence E., Reznichenko, Yakov, Yun, Chang-Han, Bhattacharya, Shanti, Swift, Jeffrey
• Granted Patent: US 6,931,170 B2
• Time in Patent Office: Days
• US Class Current: 385/18
• CPC Class Codes: G02B 6/266 the optical element being an attenuator
• CPC Class Codes: G02B 6/3512 the optical element being reflective, e.g. mirror
• CPC Class Codes: G02B 6/3556 NxM switch, i.e. regular arrays of switches elements of matrix type constellation

Abstract

A fiber-attached optical device with in-plane micromachined mirrors includes a cover having at least one reflector formed on one side and a substrate having a plurality of micromachined optical mirrors formed substantially on a single plane on a side facing toward the mirrored side of the cover. The micromachined optical mirrors are controllable to reflect optical signals between a plurality of optical fiber segments via the at least one reflector. The plurality of optical fiber segments can be attached to either the cover or the substrate so as to form an integrated package including the substrate, the cover, and the plurality of optical fiber segments. The mirrors can be controlled to variably attenuate the optical signals.

Claims

1. An apparatus comprising:

a cover having at least one reflector formed on one side;

a substrate having a plurality of micromachined optical mirrors formed substantially on a single plane on a side facing toward the mirrored side of the cover, the micromachined optical mirrors controllable to reflect optical signals between a plurality of optical fiber segments via the at least one reflector;

said plurality of optical fiber segments attached to one of the cover and the substrate so as to form an integrated package including the substrate, the cover, and the plurality of optical fiber segments.

2. The apparatus of claim 1, wherein the micromachined optical mirrors are further controllable to selectively attenuate the optical signals.

3. The apparatus of claim 1, wherein the plurality of optical fiber segments are attached using at least one of:

a fiber fusion technique;

an adhesive bonding technique;

a drilling and attachment technique;

a soldering technique; and

a glass frit technique.

4. The apparatus of claim 1, wherein the cover is plastic, and wherein the plurality of optical fiber segments are molded into the cover.

5. The apparatus of claim 1, wherein the cover is metal, and wherein each optical fiber segment penetrates through the cover.

6. The apparatus of claim 5, wherein each optical fiber segment comprises a fiber tip and a collimating lens attached to the fiber tip.

7. The apparatus of claim 5, wherein each optical fiber segment comprises a fiber tip shaped to provide collimation.

8. The apparatus of claim 1, further comprising a plurality of collimating lenses integral to said one of the cover and the substrate, wherein the plurality of optical fiber segments are attached in such a way that they align respectively with the plurality of collimating lenses.

9. The apparatus of claim 8, wherein the plurality of collimating lenses comprises at least one microlens array.

10. The apparatus of claim 1, wherein the substrate further comprises integrated electronics.

11. The apparatus of claim 1, wherein the integrated package is hermetically sealed.

12. A method for assembling an optical switching apparatus having a metal cap with an integral microlens array, the method comprising:

forming holes in the metal cap;

forming a mirror on a front side of the microlens array;

bonding the microlens array to the metal cap with the lenses aligned to the holes;

bonding the metal cap with microlens array to a substrate having a plurality of micromachined optical mirrors; and

mounting a plurality of optical fiber segments respectively into the holes.

13. The method of claim 12, wherein bonding the microlens array to the metal cap with the lenses aligned to the holes comprises:

metallizing a back side of the microlens array to produce a solderable surface; and

soldering the back side of the microlens array to the metal cap with the lenses aligned to the holes.

14. The method of claim 12, further comprising:

attaching strain relief to the capped substrate to reduce strain on the plurality of optical fiber segments during use of the optical switching apparatus.

15. An optical switching system comprising:

a substrate having a surface including a first plurality of movable mirrors and a second plurality of movable mirrors; and

a cover having at least one reflector, a plurality of input fiber collimators, and a plurality of output fiber collimators, wherein each of the first plurality of movable mirrors is controllable to direct an optical signal from an input fiber collimator to a selected one of the second plurality of movable mirrors via the at least one reflector and each of the second plurality of movable mirrors is controllable to direct an optical signal to a selected output fiber collimator.

16. The optical switching system of claim 15, wherein each input fiber collimator is positioned to direct an optical signal to a predetermined one of the first plurality of movable mirrors.

17. The optical switching system of claim 15, wherein each mirror of the first plurality of mirrors is positioned relative to the at least one reflector and to the second plurality of mirrors so as to direct an optical signal to a selected mirror of the second plurality of mirrors via the at least one reflector.

18. The optical switching system of claim 15, wherein each output fiber collimator is substantially positioned so as to receive the optical signal from a predetermined one of the second plurality of mirrors.

19. The optical switching system of claim 15, wherein the cover is substantially flat, and wherein the plurality of input fiber collimators and the plurality of output fiber collimators are positioned substantially perpendicular to a plane of the first and second plurality of movable mirrors.

20. The optical switching system of claim 15, wherein the cover is substantially flat, and wherein the plurality of input fiber collimators and the plurality of output fiber collimators are positioned at an angle to a plane of the first and second plurality of movable mirrors.

21. The optical switching system of claim 15, wherein the cover is shaped like an inverted “

V,” and

wherein the plurality of input fiber collimators and the plurality of output fiber collimators are positioned at an angle to a plane of the first and second plurality of movable mirrors.

22. The optical switching system of claim 15, wherein the cover is shaped like a four-sided pyramid, and wherein the plurality of input fiber collimators and the plurality of output fiber collimators are positioned substantially perpendicular to a plane of the first and second plurality of movable mirrors.

23. The optical switching system of claim 15, wherein the movable mirrors are controllable electronically.

24. The optical switching system of claim 15, wherein:

the plurality of input fiber collimators consists of a pair of input fiber collimators;

the first plurality of movable mirrors consists of a first pair of movable mirrors;

the second plurality of movable mirrors consists of a second pair of movable mirrors; and

the plurality of output fiber collimators consists of a pair of output fiber collimators.

25. The optical switching system of claim 15, further comprising:

control logic operably coupled to position each movable mirror for switching the optical signals between the input fiber collimators and the output fiber collimators.

26. The optical switching system of claim 25, wherein the control logic is operably coupled to further position each movable mirror for selectively attenuating each optical signals by a predetermined amount.

27. A variable optical attenuator comprising:

an optical input;

an optical output;

a movable mirror; and

control logic operably coupled to position the movable mirror so that an optical signal is directed from the optical input to the optical output with a selected amount of attenuation due to the mirror position.