Optical switch for reciprocal traffic

• US 6,650,804 B2
• Filed: 01/03/2002
• Issued: 11/18/2003
• Est. Priority Date: 07/31/2000
• Status: Expired due to Fees

• Current Assignee: Tellabs Operations Incorporated (Infinera Corp.)
• Original Assignee: Tellabs Operations Incorporated (Infinera Corp.)
• Inventors: Holmstrom, Roger P., Mills, James D., Lin, Philip J.
• Primary Examiner(s): Palmer, Phan T. H.
• Application Number:
  US10/037,054
• Publication Number:
  US 20020057864A1
• Time in Patent Office: 684 Days
• Field of Search: 385/16-18, 385/20, 385/21, 385/24, 359/117, 359/119, 359/128, 359/139, 398/108, 398/110, 398/119, 398/130
• US Class Current: 385/17
• CPC Class Codes: G02B 6/3512 the optical element being reflective, e.g. mirror
• CPC Class Codes: G02B 6/3542 Non-blocking switch, e.g. with multiple potential paths between multiple inputs and outputs, the establishment of one switching path not preventing the establishment of further switching paths
• CPC Class Codes: G02B 6/3546 NxM switch, i.e. a regular array of switches elements of matrix type constellation
• CPC Class Codes: H04Q 11/0005 Switch and router aspects
• CPC Class Codes: H04Q 2011/0024 using space switching
• CPC Class Codes: H04Q 2011/003 using switches based on microelectro-mechanical systems [MEMS]
• CPC Class Codes: H04Q 2011/0039 Electrical control
• CPC Class Codes: H04Q 2011/0056 Clos
• CPC Class Codes: H04Q 2011/0058 Crossbar; Matrix

Abstract

A reduced component optical switch module includes a plurality of ports wherein each port includes an optical input and an optical output. A plurality of switchable deflectors in combination with a plurality of non-switchable deflectors can be used to establish transmission paths between pairs of ports to support traffic reciprocity. In one embodiment, the ports and switchable elements are configured so as to provide substantially constantly transmission paths within the respective module. In another embodiment, additional deflector elements can be provided to implement loop-back functionality at one or more of the ports.

Claims

1. An optical switch comprising:

a module;

a plurality of input/output ports on the module, wherein each port can receive an optical input and can provide an optical output;

a plurality of diagonally disposed, fixed, optical path altering elements wherein each element alters an optical path within the module which path extends to a respective port; and

a plurality of multi-state optical path altering elements disposed on respective optical paths wherein each such element has a location between a respective port and a respective fixed element and wherein a transmission path is establishable between first and second ports in a selected direction and between the same two ports in an opposite direction.

2. A switch as in claim 1 which includes at least one non-diagonally disposed, fixed element located on a selected optical path.

3. A switch as in claim 2 wherein the diagonally disposed fixed elements are oriented on the order of ninety degrees relative to a non-diagonally disposed fixed element.

4. A switch as in claim 1, wherein members of a plurality of transmission paths between respective pairs of ports each have a substantially common length.

5. A switch as in claim 1 wherein at least one of the elements comprises a multi-point deflector of at least one optical path.

6. A switch as in claim 1 wherein the number of multi-state elements is on the order of one-half the total of the number of ports squared minus one.

7. A switch as in claim 1 wherein the multi-state elements comprise at least one of switchable reflectors, optical bubbles, and holographic gratings.

8. A switch as in claim 1 which has N ports and wherein the plurality of multi-state elements comprises {N* (N−

1)/2}−

1 elements.

9. A system of interconnected switches wherein at least some of the switches comprise:

a plurality of input/output ports wherein each port can receive an optical input and can provide an optical output;

a plurality of diagonally disposed fixed optical path defining elements carried within a respective switch wherein an optical path extends within the switch in part between a respective port and a respective element; and

a plurality of multi-state path defining elements disposed on respective optical paths located within a respective switch wherein each such element has a location between a respective port and a respective fixed element and wherein a transmission path is establishable between first and second ports in a selected direction and between the same two ports in an opposite direction.

10. An optical switch comprising:

a plurality of ports, some ports can at least receive an optical input and others can at least provide an optical output; and

a plurality of multi-state, optical path altering elements disposed on a plurality of respective optical paths establishable between pairs of ports, the paths comprise a substantially common length, selected pairs of ports support reciprocal traffic.

11. A switch as in claim 10 which includes:

a plurality of diagonally disposed, fixed, optical path altering elements, each element alters an optical path within the module which path extends to a respective port; and

each multi-state element has a location between a respective port and a respective fixed element.

12. A switch as in claim 11 which includes at least one non-diagonally disposed, fixed element located on a selected optical path.

13. A switch as in claim 12 with the diagonally disposed fixed elements oriented on the order of ninety degrees relative to a non-diagonally disposed fixed element.

14. A switch as in claim 11, at least some of the ports have an associated deflecting only element.

15. A switch as in claim 11, the number of multi-state elements is on the order of one-half the difference of the number of ports squared minus one.

16. A switch as in claim 11, at least some of the ports are staggered relative to one another and including at least one optical reversing element associated with at least one of the ports for providing a bi-directional transmission path to and from the respective port.

17. A switch as in claim 10, the multi-state elements comprise at least one of switchable reflectors, optical bubbles, and holographic gratings.

18. A switch as in claim 10 which has N ports and wherein the plurality of multi-state elements comprises {N*(N−

1)/2}−

1 elements.

19. A switch as in claim 10, at least some of the ports are displaced relative to others so as to establish the common path length.

20. A switch as in claim 10, the optical paths are bounded in part by at least a multi-state element and a deflecting only element.