Cables with Bend Insensitive Optical Fibers

• US 20110142403A1
• Filed: 12/11/2009
• Published: 06/16/2011
• Est. Priority Date: 12/11/2009
• Status: Active Grant

• Current Assignee: Corning Optical Communications LLC (Corning Incorporated)
• Original Assignee: Corning Cable Systems LLC (Corning Incorporated)
• Inventors: Hurley, William C.
• Granted Patent: US 8,224,140 B2
• Time in Patent Office: Days
• US Class Current: 385/102
• CPC Class Codes: B29D 11/00663 Production of light guides
• CPC Class Codes: G02B 6/02395 Glass optical fibre with a protective coating, e.g. two layer polymer coating deposited directly on a silica cladding surface during fibre manufacture G02B6/02052, G02B6/02057, G02B6/024, G02B6/032, G02B6/105, G02B6/14 take precedence; coating on fibre gratings G02B6/02104; multilayer core or cladding G02B6/036; reinforcing splice joints G02B6/2558; optical cables, i.e. comprising protective structures external to the protective coating such as a jacket or plural coated optical fibres G02B6/44; coating of glass to obtain optical fibres C03C25/104
• CPC Class Codes: G02B 6/0281 Graded index region forming part of the central core segment, e.g. alpha profile, triangular, trapezoidal core G02B6/0288, G02B6/0286 take precedence
• CPC Class Codes: G02B 6/0365 arranged - - +
• CPC Class Codes: G02B 6/4411 Matrix structure
• CPC Class Codes: G02B 6/4429 Means specially adapted for strengthening or protecting the cables
• CPC Class Codes: G02B 6/4431 with provision in the protective covering, e.g. weak line, for gaining access to one or more fibres, e.g. for branching or tapping break-out terminations G02B6/4471
• CPC Class Codes: G02B 6/4432 with fibre reinforcements

Abstract

Fiber optic cables and methods of manufacturing fiber optic cables are disclosed herein. According to one embodiment, a fiber optic cable includes a plurality of optical fibers having a lay length of greater than 160 mm. The fiber optic cable also includes strength material surrounding the plurality of optical fibers and a polymer jacket surrounding the strength material. Each of the optical fibers is configured to exhibit a bend-induced optical attenuation of less than or equal to about 0.6 dB when wrapped one turn around a 7.5 mm mandrel.

Claims

1. A fiber optic cable comprising:

a plurality of optical fibers, wherein any lay length of the optical fibers is greater than or equal to about 160 mm;

strength material surrounding the plurality of optical fibers, wherein any lay length of the strength material is greater than or equal to about 130 mm; and

a polymer jacket surrounding the strength material;

wherein each of the optical fibers is configured to exhibit a bend-induced optical attenuation of less than or equal to about 0.6 dB when wrapped one turn around a 7.5 mm mandrel.

2. The fiber optic cable of claim 1, wherein the strength material comprises strength members that are substantially parallel to one another.

3. The fiber optic cable of claim 1, wherein the strength material is stranded around the plurality of optical fibers, so that the lay length of the strength material is greater than or equal to about 500 mm.

4. The fiber optic cable of claim 2, wherein the strength material has a lay length greater than or equal to about 1000 mm.

5. The fiber optic cable of claim 1, wherein the plurality of optical fibers are substantially parallel to one another.

6. The fiber optic cable of claim 1, wherein the plurality of optical fibers is stranded, so that the lay length of the plurality of optical fibers is greater than or equal to about 500 mm.

7. The fiber optic cable of claim 6, wherein the lay length of the plurality of optical fibers is greater than or equal to about 1000 mm.

8. The fiber optic cable of claim 1, wherein each of the optical fibers is configured to exhibit a bend-induced optical attenuation of less than or equal to about 0.2 dB when wrapped one turn around a 7.5 mm mandrel.

9. The fiber optic cable of claim 1, wherein each of the optical fibers is a configured to exhibit a bend-induced optical attenuation of less than or equal to about 0.08 dB when wrapped one turn around a 7.5 mm mandrel.

10. The fiber optic cable of claim 1, wherein each of the optical fibers is tight buffered optical fiber.

11. The fiber optic cable of claim 1, wherein the strength material comprises aramid fibers.

12. A fiber optic cable comprising:

a plurality of tight buffered optical fibers having a lay length of greater than 160 mm;

strength material surrounding the plurality of tight buffered optical fibers; and

a polymer jacket surrounding the strength material;

wherein each of the tight buffered optical fibers is configured to exhibit a bend-induced optical attenuation of less than or equal to about 0.6 dB when wrapped one turn around a 7.5 mm mandrel.

13. The fiber optic cable of claim 12, wherein the plurality of tight buffered optical fibers are substantially parallel to one another.

14. The fiber optic cable of claim 12, wherein the lay length of the plurality of tight buffered optical fibers is greater than or equal to about 500 mm.

15. The fiber optic cable of claim 12, wherein each of the tight buffered optical fibers is configured to exhibit a bend-induced optical attenuation of less than or equal to about 0.2 dB when wrapped one turn around a 7.5 mm mandrel.

16. The fiber optic cable of claim 12, wherein each of the tight buffered optical fibers is configured to exhibit a bend-induced optical attenuation of less than or equal to about 0.08 dB when wrapped one turn around a 7.5 mm mandrel.

17. The fiber optic cable of claim 12, wherein the strength material comprises strength members that are substantially parallel to one another.

18. The fiber optic cable of claim 12, wherein the strength material has a lay length greater than or equal to about 500 mm.

19. The fiber optic cable of claim 12, wherein the strength material has a lay length greater than or equal to about 1000 mm.

20. The fiber optic cable of claim 19, wherein the strength material comprises aramid fibers.

21. The fiber optic cable of claim 12, wherein:

a first group of the tight buffered optical fibers resides within an inner layer and a second group of the tight buffered optical fibers resides within an outer layer; and

the first group is immediately adjacent to the second group.

22. The fiber optic cable of claim 12, wherein each of the tight buffered optical fibers exhibits an intrinsic optical attenuation of less than or equal to about 3.0 dB/km.

23. The fiber optic cable of claim 12, wherein there are at least 24 of the tight buffered optical fibers in the fiber optic cable.

24. A method of manufacturing a fiber optic cable, the method comprising:

stranding a plurality of optical fibers with a lay length of greater than 160 mm, wherein each optical fiber exhibits a bend-induced attenuation of less than or equal to about 0.6 dB when wrapped one turn around a 7.5 mm mandrel;

surrounding the plurality of optical fibers with strength material; and

extruding a polymer jacket around the strength material.

25. The method of claim 24, wherein the stranding of the optical fibers comprises positioning at least one optical fiber within an inner layer and at least one optical fiber within an outer layer, and arranging the outer layer immediately adjacent to the inner layer.

26. The method of claim 24, comprising performing the stranding, surrounding, and extruding at a line speed of at least 30 meters per minute.