Apparatus and Manufacturing Method for an Integrated Multicast Switch, For Use in Reconfigurable Optical Add-Drop Networks

• US 20150244492A1
• Filed: 09/25/2014
• Published: 08/27/2015
• Est. Priority Date: 02/21/2014
• Status: Active Grant

• Current Assignee: DiCon Fiber Optics Incorporated
• Original Assignee: DiCon Fiber Optics Incorporated
• Inventors: Lee, Ho-Shang
• Granted Patent: US 9,998,252 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G02B 2006/1215 Splitter
• CPC Class Codes: G02B 6/30 for use between fibre and thin-film device
• CPC Class Codes: G02B 6/3512 the optical element being reflective, e.g. mirror
• CPC Class Codes: G02B 6/3546 NxM switch, i.e. a regular array of switches elements of matrix type constellation
• CPC Class Codes: G02B 6/3636 the mechanical coupling means being grooves G02B6/3652 takes precedence
• CPC Class Codes: H04J 14/0212 using optical switches or wavelength selective switches [WSS]
• CPC Class Codes: H04Q 11/0005 Switch and router aspects
• CPC Class Codes: H04Q 2011/0015 using splitting combining
• CPC Class Codes: H04Q 2011/003 using switches based on microelectro-mechanical systems [MEMS]
• CPC Class Codes: H04Q 2011/0035 using miscellaneous components, e.g. circulator, polarisation, acousto/thermo optical
• CPC Class Codes: H04Q 2011/0047 Broadcast; Multicast

Abstract

In one embodiment, each of the output/input ports of each one of a plurality of optical splitters is connected to one of a plurality of optical switches by means of optical fibers without any fusion splicing in a majority of the optical fibers, and each of the input/output ports of each one of the switches is connected to one of the optical splitters by means of the optical fibers without any fusion splicing in a majority of the optical fibers. Each of the output/input ports of each one of the optical splitters may be directly connected to the ferrule and one of the input/output ports of one of the switches by the optical fibers. The optical splitters may be implemented in at least one planar lightwave circuit (PLC) chip. Optionally, at least one fiber holder defining a plurality of channels therein may be used to hold the optical fibers each of which is aligned with a corresponding output/input port of one of the optical splitters.

Claims

1. A multicast optical switching device comprising:

M optical splitters, each having one input/output port and N output/input ports, and thereby designated as an 1×

N optical splitter, M and N being integers greater than 1;

N optical switches, each having a ferrule, M input/output ports and one output/input port, and thereby designated as a M×

1 optical switch;

a first set of optical fibers, each of the fibers in the first set connecting one of the N output/input ports of one of the optical splitters to the ferrule and one of the input/output ports of one of the N switches, wherein each of the N output/input ports of each one of the optical splitters is connected to one of the N switches by means of the optical fibers in the first set without any fusion splicing in a majority of said optical fibers in the first set, and each of the M input/output ports of each one of the switches is connected to one of the M optical splitters by means of the optical fibers in the first set without any fusion splicing in a majority of said optical fibers in the first set; and

a second set of N optical fibers;

said ferrule of each of said N optical switches housing the M optical fibers in the first set connected to the M input/output ports of such switch and an optical fiber in the second set connected to the one output/input port of such switch.

2. The device of claim 1, each of said N optical switches further comprising a lens and a movable MEMS mirror that are aligned with the ferrule of such optical switch.

3. The device of claim 2, wherein said ferrule of each of the N switches is fixed in position relative to the lens of such switch.

4. The device of claim 2, further comprising a third set of M optical fibers each connected to the input/output port of one of the M optical splitters, wherein by controlling a position of the MEMS mirror in each of the optical switches, radiation from any one of the M optical fibers in the third set is transmitted to a selected one of the optical fibers in the second set in a forward direction, and radiation from any one of the N optical fibers in the second set is transmitted to a selected one of the M optical fibers in the third set in a reverse direction.

5. The device of claim 1, further comprising an anti-reflection coating on an end face of the ferrule of at least one of the switches.

6. A multicast optical switching device comprising:

at least one planar lightwave circuit (PLC) chip that contain(s) M optical splitters, each splitter having one input/output port and N output/input ports, and thereby designated as an 1×

N optical splitter, M and N being integers greater than 1;

N optical switches, each having M input/output ports and one output/input port and thereby designated as a M×

1 optical switch;

at least one fiber holder defining a plurality of channels therein; and

a first set of optical fibers, each of the optical fibers in the first set being held in one of the fiber holder channels and aligned with a corresponding output/input port of one of the optical splitters, each of the optical fibers and the corresponding output/input port defining there between a corresponding optical path,

wherein each of the N output/input ports of each one of the optical splitters is connected to one of the N switches by means of the optical fibers in the first set and through the corresponding optical path, without any fusion splicing in a majority of said optical fibers in the first set, and each of the M input/output ports of each one of the switches is connected to one of the M optical splitters by means of the optical fibers in the first set and through the corresponding optical path, without any fusion splicing in a majority of said optical fibers in the first set.

7. The device of claim 6, wherein each channel of said M fiber holders includes a V-groove for holding an optical fiber.

8. The device of claim 6, said device comprising M planar lightwave circuit (PLC) chips and M fiber holders, each of the PLC chips containing one of the M optical splitters, each of the fiber holders holding the N optical fibers that are connected to an input/output port of each of the N switches and to the N output/input ports of a corresponding one of the M optical splitters.

9. The device of claim 8, each of said PLC chips including a waveguide structure comprising a cascaded series of 1×

2 splitter elements.

10. The device of claim 8, wherein each of the M fiber holders is bonded to the corresponding one of the M optical splitters to form a sub-assembly.

11. The device of claim 8, further comprising an anti-reflection coating on an end face of at least one of the M fiber holders and an anti-reflection coating on an end face of the optical splitter corresponding to said at least one M fiber holder.

12. The device of claim 8, each of said N switches further comprising a lens and movable MEMS mirror that are aligned with a ferrule containing the M input/output ports and one output/input port of such switch.

13. The device of claim 12, wherein by controlling a position of the MEMS mirror in each of the optical switches, radiation from the output/input port of a selected one of the M splitters is transmitted to the output/input port of any one of the N switches in a forward direction, and radiation from the output/input port of a selected one of the N switches is transmitted to the output/input port of any one of the M splitters in a reverse direction, through the first set of optical fibers.

14. The device of claim 6, wherein at least some of the output/input ports of the M optical splitters are spaced apart by a distance in between adjacent output/input ports, and at least some of the channels are spaced apart by substantially said distance in between adjacent channels.

15. A method for making a multicast optical switching device comprising:

providing M optical splitters, each having one input/output port and N output/input ports, designated as an 1×

N optical splitter, M and N being integers greater than 1;

providing N optical switches, each having a ferrule, M input/output ports and one output/input port, designated as a M×

1 optical switch; and

directly connecting each one of the N output/input ports of each one of the optical splitters to the ferrule and one of the input/output ports of one of the N switches by means of an optical fiber in a set of optical fibers, so that each of the N output/input ports of each one of the optical splitters is connected to one of the N switches by means of optical fibers without any fusion splicing in the majority of said optical fibers in the set, and each of the M input/output ports of each one of the switches is connected to one of the M optical splitters without any fusion splicing in the majority of said optical fibers in the set.

16. The method of claim 15, further comprising aligning the ferrule of each of the switches with a corresponding lens and a corresponding movable MEMS mirror after the output/input ports of the M optical splitters are connected to the ferrules of the N optical switches.

17. A method for making a multicast optical switching device comprising:

providing at least one planar lightwave circuit (PLC) chip that contains M optical splitters, each splitter having one input/output port and N output/input ports, and thereby designated as an 1×

N optical splitter, M and N being integers greater than 1;

providing N optical switches, each having M input/output ports and one output/input port and thereby designated as a M×

1 optical switch, and M optical fibers each connected to one of the M input/output ports of such switch;

providing at least one fiber holder defining a plurality of channels therein;

causing each of said optical fibers of the N optical switches to be held in one of the plurality of channels;

aligning each of the optical fibers held in one of the channels with a corresponding output/input port of one of the optical splitters, each of the optical fibers and the output/input port aligned with such optical fiber defining there between a corresponding optical path;

wherein each of the N output/input ports of each one of the optical splitters is connected to one of the N switches by means of an optical fiber and through its corresponding optical path without any fusion splicing in the majority of said optical fibers, and each of the M input/output ports of each one of the switches is connected to one of the M optical splitters by means of an optical fiber and through its corresponding optical path without any fusion splicing in the majority of said optical fibers.

18. The method of claim 17, wherein said at least one planar lightwave circuit (PLC) chip is made by forming waveguide structures on a surface of a substrate to implement the M optical splitters formed by a cascaded series of 1×

2 splitters.

19. The method of claim 17, wherein said at least one fiber holder is made by forming V groove structures on a surface of a substrate to implement the channels, each of the V groove structures suitable for holding an optical fiber.

20. The method of claim 19, wherein at least some of the output/input ports of the M optical splitters are spaced apart by a distance in between adjacent output/input ports, and at least some of the V groove structures are spaced apart by substantially said distance in between adjacent V groove structures.