COATED OPTICAL FIBER, OPTICAL FIBER RIBBON, AND OPTICAL CABLE

• US 20150293325A1
• Filed: 06/04/2014
• Published: 10/15/2015
• Est. Priority Date: 02/17/2012
• Status: Active Grant

• Current Assignee: Furukawa Electric Company Limited
• Original Assignee: Furukawa Electric Company Limited
• Inventors: KASAHARA, Minoru, SAITO, Minoru, ARASHITANI, Yoshihiro
• Granted Patent: US 9,846,292 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• 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 6/4403 with ribbon structure G02B6/4429, G02B6/4439, G02B6/4479 take precedence
• CPC Class Codes: G02B 6/4404 Multi-podded
• CPC Class Codes: G02B 6/44384 the means comprising water blocking or hydrophobic materials G02B6/4439, G02B6/4479 take precedence

Abstract

The purpose of the present invention is to provide, by a configuration or method different from conventional art, a coated optical fiber enabling reduced interface delamination between a glass fiber and a primary coating layer when the coated optical fiber is immersed in water, and a reduction of transmission loss increase. A coated optical fiber according to one embodiment of the present invention is provided with a glass fiber, a primary coating layer coated on the glass fiber, a secondary coating layer coated on the primary coating layer, and a colored layer coated on the secondary coating layer. The coated optical fiber is configured so that small water bubbles are generated substantially evenly within the primary coating layer when the coated optical fiber is immersed for 200 days in warm water of 60° C.

Claims

1. A coated optical fiber comprising:

an optical fiber including a glass fiber, a primary coating layer coating an outer periphery of the glass fiber, and a secondary coating layer coating an outer periphery of the primary coating layer; and

a tertiary coating layer coating an outer periphery of the optical fiber and having an elastic modulus of 100 MPa or higher, wherein

when the coated optical fiber is immersed in hot water at 60°

C. for 200 days, water bubbles are formed substantially evenly inside the primary coating layer,

a number of the water bubbles present per unit area in the primary coating layer on a cross-section taken along a longitudinal direction of the coated optical fiber is one or more, the unit area being defined with a thickness of the primary coating layer being taken as one unit, and

the water bubbles have diameters of 10 μ

m or less.

2. The coated optical fiber according to claim 1, wherein

a first load which causes delamination at a 50% probability when applied to the coated optical fiber in a direction perpendicular to the longitudinal direction of the coated optical fiber is larger than a second load which causes tearing at a 50% probability when applied to the coated optical fiber in the direction perpendicular to the longitudinal direction of the coated optical fiber.

3. The coated optical fiber according to claim 2, wherein

the first load is 500 g or more, and

the second load is 200 g or more.

4. The coated optical fiber according to claim 1, wherein

the tertiary coating layer is a colored layer.

5. An optical fiber ribbon comprising:

a plurality of the coated optical fibers according to claim 4 arranged in parallel to each other and coated together.

6. An optical fiber cable comprising:

a plurality of the optical fiber ribbons according to claim 5 stacked on each other; and

a slot in which the optical fiber ribbons are housed.

7. An optical fiber ribbon comprising:

a plurality of optical fibers each of which includes a glass fiber, a primary coating layer coating an outer periphery of the glass fiber, and a secondary coating layer coating an outer periphery of the primary coating layer and which are arranged in parallel to each other; and

a ribbon coating layer being a tertiary coating layer having an elastic modulus of 100 MPa or higher and coating the optical fibers together, wherein

when the optical fiber ribbon is immersed in hot water at 60°

C. for 200 days, water bubbles are formed substantially evenly inside the primary coating layer,

a number of the water bubbles present per unit area in the primary coating layer on a cross-section taken along a longitudinal direction of the optical fiber ribbon is one or more, the unit area being defined with a thickness of the primary coating layer being taken as one unit, and

the water bubbles have diameters of 10 μ

m or less.

8. An optical fiber cable comprising:

a plurality of the optical fiber ribbons according to claim 7 stacked on each other; and

a slot in which the optical fiber ribbons are housed.