Reduced diameter multimode optical fiber cables

Patent metadata

Field	Value
Publication number	US-9541723-B2
Application number	US-201314771910-A
Country	US
Kind code	B2
Filing date	Mar 4, 2013
Priority date	Mar 4, 2013
Publication date	Jan 10, 2017
Grant date	Jan 10, 2017

Abstract

Described are new cable designs for indoor installations wherein the cable comprises a dual-layer optical fiber buffer encasement of acrylate resin. The buffer encasement has an acrylate compliant inner layer that protects the fiber and minimizes stress transfer to the fiber; and a hard, tough acrylate outer layer that provides crush resistance. The dual-layer optical fiber buffer encasement is wrapped with reinforcing yarn and encased in an outer protective jacket. The protective jacket is relatively thick and rigid, having a thickness of 0.7-3.0 mm, and a modulus greater than 240 MPa.

First claim

The invention claimed is:

1. An optical fiber cable comprising:
(a) at least one optical fiber buffer encasement, each encasement comprising:
i. at least two 50 micron multimode optical fibers encased in a polymer matrix, the polymer matrix comprising a UV cured acrylate having a modulus in the range 0.5 to 10 MPa,
ii. a UV cured acrylate polymer encasement, with a modulus in the range 200 MPa to 1000 MPa encasing the polymer matrix, the acrylate polymer encasement and the polymer matrix having a round cross section,

(b) a yarn wrap strength layer surrounding a grouping of the at least one optical fiber buffer encasements,
(c) a cable jacket surrounding the yarn wrap strength layer, the first cable jacket consisting essentially of polymer material having:
i. a round cross section,
ii. a thickness of 0.7-3.0 mm,
iii. a modulus greater than 240 MPa,

(d) sufficient flame retardant to meet one or more industry fire protection standards.

2. The optical fiber cable of claim 1 wherein the optical fiber cable comprises more than one encasement.

3. The optical fiber cable of claim 2 wherein the optical fiber cable comprises 2-12 encasements.

4. The optical fiber cable of claim 2 wherein the glass transition temperature of the polymer encasement is greater than 40 degrees C.

5. The optical fiber cable of claim 2 wherein the yarn wrap is polyaramid yarn.

6. The optical fiber cable of claim 2 wherein the modulus of the cable jacket is in the range of 300-500 MPa.

7. The optical fiber cable of claim 2 wherein the thickness of the cable jacket is in the range 1.0-2.0 mm.

8. The optical fiber of claim 2 wherein the standard of limitation (d) is the National Fire Protection Association NFPA 202-2011 standard.

9. The optical fiber of claim 2 wherein the standard of limitation (d) is selected from the group consisting essentially of NFPA 262-2011, IEC 60332-3-24, IEC 61034-2, Class D, Class C, and Class B2 of the EN 50399.

10. The optical fiber cable of claim 2 wherein the optical fiber cable is a non-halogen cable.

Assignees

• Ofs Fitel Llc

Inventors

• Ly Heng
• Weimann Peter A

Classifications

• G02B6/4432 Primary

  with fibre reinforcements · CPC title

• G02B6/4436

  Heat resistant · CPC title