Preferential mode coupling for enhanced traceable patch cord performance

Patent metadata

Field	Value
Publication number	US-10107983-B2
Application number	US-201615142853-A
Country	US
Kind code	B2
Filing date	Apr 29, 2016
Priority date	Apr 29, 2016
Publication date	Oct 23, 2018
Grant date	Oct 23, 2018

Abstract

A traceable cable and method of forming the same. The cable includes at least one data transmission element, a jacket, and a side-emitting optical fiber. The side-emitting optical fiber includes a core having a first index of refraction and a cladding having a second index of refraction that is different than the first index of refraction. The cladding substantially surrounding the core and has an exterior surface with spaced apart scattering sites penetrating the exterior surface. The scattering sites are capable of scattering light so that the scattered light is emitted from the side-emitting optical fiber at discrete locations. The core also includes one or more mode coupling features capable of changing at least some low order mode light in the side-emitting optical fiber to high order mode light, thereby increasing light emitted from the scattering sites.

First claim

What is claimed is:

1. A traceable cable having a length, comprising:
at least one data transmission element;
a jacket at least partially surrounding the at least one data transmission element; and
a side-emitting optical fiber extending along at least a portion of the length of the cable, wherein the side-emitting optical fiber comprises:
a core having a first index of refraction; and
a cladding having a second index of refraction that is different than the first index of refraction, the cladding substantially surrounding the core, the cladding having an exterior surface,
wherein the cladding comprises spaced apart scattering sites, the scattering sites being capable of scattering light so that the scattered light is emitted from the side-emitting optical fiber at discrete locations,
wherein the core further comprises one or more mode coupling features capable of changing at least some low order mode light in the side-emitting optical fiber to high order mode light,
wherein, when light is transmitted through the side-emitting optical fiber, light scattered from the side-emitting optical fiber allows the cable to be traced along at least a portion of the length thereof,
wherein the high order mode light has an effective refractive index between a cladding refractive index and an average of the cladding refractive index and a core refractive index, while low order mode light has an effective refractive index between the core refractive index and the average of the cladding refractive index and the core refractive index.

2. The traceable cable of claim 1 , wherein the one or more mode coupling features comprises an index perturbation.

3. The traceable cable of claim 1 , wherein the index perturbation is an ellipsoidal index perturbation.

4. The traceable cable of claim 1 , wherein the one or more mode coupling features comprises a deformation of a geometry of the core of the side-emitting optical fiber.

5. The traceable cable of claim 1 , wherein the one or more mode coupling features comprises an index perturbation and a deformation of a geometry of the core of the side-emitting optical fiber.

6. The traceable cable of claim 1 , wherein the side-emitting optical fiber comprises a plurality of mode coupling features and at least one mode coupling feature of the plurality of mode coupling features is located between each pair of scattering sites.

7. The traceable cable of claim 6 , wherein the plurality of mode coupling features are periodically spaced along the length of the traceable cable between about 4 cm and about 1 m apart.

8. The traceable cable of claims 6 , wherein a distance between adjacent mode coupling features varies as a function of the distance from an end of the side-emitting optical fiber.

9. The traceable cable of claim 1 , wherein the one or more mode coupling features is capable of changing at least some of the low order mode light into the high order mode light.

10. The traceable cable of claim 1 , wherein the side-emitting optical fiber is at least partially embedded in the jacket.

11. The traceable cable of claim 1 , wherein the side-emitting optical fiber is a step-index optical fiber.

12. The traceable cable of claim 1 , further comprising a first connector at a first end of the traceable cable and a second connector at a second end of the traceable cable.

13. A method of forming a traceable cable that includes at least one data transmission element and a jacket at least partially surrounding the at least one data transmission element, the method comprising:
forming a side-emitting optical fiber by:
adding a cladding around a core to create an exterior surface, the cladding having a different index of refraction than the core;
creating scattering sites in the exterior surface configured to allow the side-emitting optical fiber to scatter light therefrom;
and modifying portions of the core to create mode coupling features capable of changing at least some low order mode light in the side-emitting optical fiber to high order mode light, and

at least partially embedding the side-emitting optical fiber within the jacket so that the side-emitting optical fiber extends along at least a portion of a length of the cable;
wherein modifying portions of the core to create mode coupling features comprises exposing the portions of the core to UV light;
wherein the portions of the core are exposed to UV light to create the mode coupling features after the cladding is added around the core and after portions of the cladding have been selectively ablated to create the scattering sites.

14. The method of claim 13 , wherein modifying portions of the core to create mode coupling features comprises deforming a diameter of an outer surface of the core.

15. The method of claim 13 , wherein modifying portions of the core to create mode coupling features comprises both exposing the portions of the core to UV light and deforming a diameter of an outer surface of the core of the side-emitting optical fiber.

16. The method of claim 13 , further comprising securing a first connector at a first end of the traceable cable and securing a second connector at a second end of the traceable cable.

17. A traceable cable having a length, comprising:
at least one data transmission element;
a jacket at least partially surrounding the at least one data transmission element; and
a side-emitting optical fiber incorporated with and extending along at least a portion of the length of the cable, wherein the side-emitting optical fiber is at least partially embedded in the jacket, the side-emitting optical fiber comprising:
a core having a first index of refraction; and
a cladding having a second index of refraction that is different than the first index of refraction, the cladding substantially surrounding the core, the cladding having an exterior surface,
wherein the cladding comprises spaced apart scattering sites penetrating the exterior surface, the scattering sites being capable of scattering light so that the scattered light is emitted from the side-emitting optical fiber at discrete locations,
wherein the core further comprises spaced apart mode coupling features capable of changing at least some low order mode light in the side-emitting optical fiber to high order mode light, wherein each mode coupling feature is located between a pair of the scattering sites,
wherein, when light is transmitted through the side-emitting optical fiber, light scattered from the side-emitting optical fiber allows the cable to be traced along at least a portion of the length thereof,
wherein the high order mode light has an effective refractive index between a cladding refractive index and an average of the cladding refractive index and a core refractive index, while low order mode light has an effective refractive index between the core refractive index and the average of the cladding refractive index and the core refractive index.

Assignees

• Corning Optical Communications LLC

Inventors

• Modavis Robert Adam

Classifications

• G02B6/4495

  Physics · mapped topic

• G02B6/447 Primary

  Physics · mapped topic

• G02B6/14

  Mode converters · CPC title

• G02B6/001

  the light being emitted along at least a portion of the lateral surface of the fibre · CPC title

• G02B6/562 Primary

  locatable, e.g. using magnetic means · CPC title