Fiber optic drop terminals for multiple dwelling units

• US 20080205843A1
• Filed: 02/28/2007
• Published: 08/28/2008
• Est. Priority Date: 02/28/2007
• Status: Active Grant

• Current Assignee: Corning Optical Communications LLC (Corning Incorporated)
• Original Assignee: Corning Cable Systems LLC (Corning Incorporated)
• Inventors: Rodriguez, Diana, Castonguay, Guy, Cox, Terry Dean, Prevratil, Karyne Poissant, Liggett, Thomas Shaw, Clapp, Donnie Ray
• Granted Patent: US 7,499,622 B2
• Time in Patent Office: Days
• US Class Current: 385/135
• CPC Class Codes: G02B 6/3897 Connectors fixed to housings, casing, frames or circuit boards G02B6/44528 takes precedence
• CPC Class Codes: G02B 6/4442 Cap coupling boxes
• CPC Class Codes: G02B 6/4452 Distribution frames
• CPC Class Codes: H04Q 1/021 using pivoting mechanisms for accessing the interior of the apparatus
• CPC Class Codes: H04Q 1/023 using sliding mechanisms for accessing the interior of the apparatus
• CPC Class Codes: H04Q 1/028 Subscriber network interface devices

Abstract

There is provided fiber drop terminals (“FDTs”) and related equipment for providing selective connections between optical fibers of distribution cables and optical fibers of drop cables, such as in multiple dwelling units. The FDTs require relatively little area and/or volume while providing convenient connectivity for a relatively large number of optical connections. The FDTs include adapters for optically connecting the connectors, and the adapters of some FDTs are adapted to rotate, move, or otherwise be removed to provide convenient access for technicians. Some FDTs and the related equipment are adapted for use with microstructured optical fiber having preferred bend characteristics.

Claims

1. A fiber drop terminal (“

FDT”

) adapted for use in a fiber optic network of a multiple dwelling unit to selectively optically connect at least one connectorized optical fiber of a distribution cable to a connectorized optical fiber of at least one drop cable, the FDT comprising;

a base defining a back wall and at least one sidewall extending outwardly from the back wall, wherein the base defines at least one opening for passage of the distribution cable and the drop cable through at least one of the back wall and sidewall;

a cover adapted to selectively connect to the sidewall generally opposite the back wall; and

at least one plurality of adapters joined to at least one of the back wall and the sidewall of the base, wherein the adapters are adapted to receive a connector of the distribution cable and a connector of the drop cable to optically connect the connectorized optical fiber of the distribution cable to the connectorized optical fiber of the drop cable;

wherein the plurality of adapters is pivotably joined with a bracket mounted to the base.

2. An FDT according to claim 1, wherein the cover slideably engages the sidewall of the base.

3. An FDT according to claim 1, wherein the cover is rotatably connected to the sidewall of the base.

4. An FDT according to claim 1, wherein the plurality of adapters are connected with a vertical bar, and wherein the vertical bar comprises a horizontal hinge and a latch adapted to enable selective rotation of the plurality of adapters about a generally horizontal axis.

5. An FDT according to claim 4, wherein the horizontal hinge is provided at a bottom end of the vertical bar and the latch is provided at a top end of the vertical bar.

6. An FDT according to claim 1, wherein the plurality of adapters are connected with a vertical bar, and wherein the vertical bar is joined to the base by a bracket at each end of the vertical bar, and wherein the bracket defines a slot adapted to enable selective rotation of the plurality of adapters about a generally vertical axis.

7. An FDT according to claim 1, wherein the at least one plurality of adapters comprises a first plurality of adapters connected with a vertical bar and a second plurality of adapters connected with a vertical bar, and wherein the first plurality of adapters are provided a first distance from the back wall and the second plurality of adapters are provided a second distance from the back wall, the first distance being different than the second distance.

8. An FDT according to claim 1 further comprising a splice tray mounted to the base to enable splicing to a connectorized pigtail of at least one of an optical fiber of the distribution cable and an optical fiber of the drop cable.

9. An FDT according to claim 8, wherein the splice tray comprises a slot to selectively receive a tab protruding from the back wall of the base to enable selective mounting of the splice tray to the base.

10. An FDT according to claim 1, wherein the at least one opening of the base comprises an opening adapted to receive a multi-fiber adapter.

11. An FDT according to claim 10 further comprising a fanout device to optically connect the multi-fiber adapter to the plurality of adapters.

12. An FDT according to claim 1, wherein the at least one opening of the base comprises an opening adapted to receive a grommet comprising an opening for each of the drop cables.

13. An FDT according to claim 1, wherein the plurality of adapters define axes that are generally oriented along a plane generally parallel to the back wall of the base.

14. An FDT according to claim 1, wherein plurality of adapters define axes that are generally orthogonal to the back wall of the base.

15. An FDT according to claim 1, wherein the FDT is adapted to receive at least one optical fiber comprising a microstructured optical fiber comprising a core region and a cladding region surrounding the core region, the cladding region comprising an annular hole-containing region comprised of non-periodically disposed holes.

16. An FDT according to claim 15, wherein the microstructured fiber has an 8 mm macrobend induced loss at 1550 nm of less than 0.2 dB/turn.

17. A strain relief device adapted for use with microstructured optical fiber, the strain relief device comprising:

a body defining an axis generally aligned with the axis of the microstructured optical fibers to be strain relieved;

a plurality of slots adapted to receive the microstructured optical fibers; and

a compression device adapted for positioning around the body and the microstructured optical fibers received within the plurality of slots to apply a force upon the microstructured optical fibers to strain relieve the optical fibers.

18. A strain relief device according to claim 17, wherein the body defines a generally cylindrical shape.

19. A strain relief device according to claim 17, wherein the plurality of slots is defined along the perimeter of the body such that a portion of the microstructured optical fibers is positioned radially outward of the perimeter of the body.

20. A strain relief device according to claim 17, wherein the body defines a circumferential slot adapted to receive the compression device, wherein the slot defines at least one shoulder to prevent axial movement of the compression device.

21. A strain relief device according to claim 17, wherein the compression device comprises a wire tie device.

22. A strain relief device according to claim 17 further comprising a spring clip to selectively mount the strain relief device within a fiber optic enclosure.

23. A strain relief device according to claim 17, wherein the FDT is adapted to receive at least one optical fiber comprising a microstructured optical fiber comprising a core region and a cladding region surrounding the core region, the cladding region comprising an annular hole-containing region comprised of non-periodically disposed holes.

24. A strain relief device according to claim 23, wherein the microstructured fiber has an 8 mm macrobend induced loss at 1550 nm of less than 0.2 dB/turn.

25. A fiber drop terminal (“

FDT”

) adapted for use in a fiber optic network of a multiple dwelling unit to selectively optically connect at least one connectorized optical fiber of a distribution cable to a connectorized optical fiber of at least one drop cable, the FDT comprising;

a base defining a back wall and at least one sidewall extending outwardly from the back wall, wherein the base defines at least one opening for passage of the distribution cable and the drop cable through at least one of the back wall and sidewall;

a cover adapted to selectively connect to the sidewall generally opposite the back wall;

at least one plurality of adapters joined to at least one of the back wall and the sidewall of the base, wherein the adapters are adapted to receive a connector of the distribution cable and a connector of the drop cable to optically connect the connectorized optical fiber of the distribution cable to the connectorized optical fiber of the drop cable; and

a distribution cover provided between the back wall and the cover, wherein the distribution cover is adapted to provide limited access to the portion of the adapters that are adapted to receive a connector of the distribution cable.

26. An FDT according to claim 25, wherein the cover is rotatably attached to the base and the distribution cover is rotatably attached to the base.

27. An FDT according to claim 25 further comprising a fanout positioned between the distribution cover and the base and optically connecting the optical fiber of the distribution cable with the portion of the adapters that are adapted to receive a connector of the distribution cable.

28. An FDT according to claim 25, wherein the at least one opening of the base comprises an opening adapted to receive a multi-fiber adapter.

29. An FDT according to claim 25, wherein the at least one opening of the base comprises an opening adapted to strain relieve and seal the drop cables passing therethrough.

30. An FDT according to claim 25, wherein the FDT is adapted to receive at least one optical fiber comprising a microstructured optical fiber comprising a core region and a cladding region surrounding the core region, the cladding region comprising an annular hole-containing region comprised of non-periodically disposed holes.

31. An FDT according to claim 30, wherein the microstructured fiber has an 8 mm macrobend induced loss at 1550 nm of less than 0.2 dB/turn.

32. A fiber drop terminal (“

FDT”

) adapted for use in a fiber optic network of a multiple dwelling unit to selectively optically connect at least one connectorized optical fiber of a distribution cable to a connectorized optical fiber of at least one drop cable, the FDT comprising;

a base defining a back wall and at least one sidewall extending outwardly from the back wall, wherein the base defines at least one opening for passage of the distribution cable and the drop cable through at least one of the back wall and sidewall;

a cover adapted to selectively connect to the base; and

at least one plurality of adapters joined to a bracket attached to at least one of the back wall and the sidewall of the base, wherein the adapters are adapted to receive a connector of the distribution cable and a connector of the drop cable to optically connect the connectorized optical fiber of the distribution cable to the connectorized optical fiber of the drop cable;

wherein the bracket is selectively movable relative to the base.

33. An FDT according to claim 32, wherein the bracket is selectively detachable from the base.

34. An FDT according to claim 32, wherein the bracket is selectively rotatable relative to the base.

35. An FDT according to claim 34, wherein the bracket is selectively rotatable about a horizontal axis.

36. An FDT according to claim 32, wherein the at least one plurality of adapters comprises a first plurality of adapters and a second plurality of adapters joined to the bracket, and wherein the first plurality of adapters define axes that are angled relative to axes of the second plurality of adapters.

37. An FDT according to claim 32, wherein the cover generally defines a dome.

38. An FDT according to claim 32, wherein the cover comprises at least one latch device adapted to selectively retain the cover relative the base.

39. An FDT according to claim 32, wherein the at least one opening of the base comprises one opening for the distribution cable and a plurality of openings for the drop cables.

40. An FDT according to claim 32, wherein the at least one opening of the base comprises at least one slot adapted allow passage of two or more drop cables.

41. An FDT according to claim 40, wherein the slot defines at least one opened portion sized to allow passage of the connector of the drop cable and the slot further defines other portions sized to allow passage of the drop cable alone.

42. An FDT according to claim 32 further comprising a strain relief device adapted to be selectively received in the opening of the base and adapted to strain relieve and seal at least one of the distribution cable and the drop cable.

43. An FDT according to claim 42, wherein the strain relief device comprises a generally frustoconical device defining at least one rib along a frustoconical surface.