Optical fiber cable
AssigneesSumitomo Electric Industries, Ltd., Nippon Telegraph and Telephone Corporation
InventorsTomoyuki Yokokawa, Yoshiyuki Suetsugu, Hideyuki Iwata
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Abstract
An optical fiber cable in which optical fiber ribbon stack can be accommodated in a cylindrical space efficiently and which has excellent loss characteristic. A plurality of optical fiber ribbons 1 are stacked. Cushioning fillers 2 are disposed around the optical fiber ribbon stack 1. The optical fiber ribbon stack 1 and the cushioning fillers 2 are accommodated in a cylindrical member 3. The space factor of the cushioning fillers in the inner space of the cylindrical member as a remainder after removal of the optical fiber ribbon stack from the inner space is from 10 to 60%. Consequently, the optical fiber cable becomes excellent both in initial transmission loss and in loss increasing characteristic at a low temperature.
Claims11
An optical fiber cable comprising:
- a plurality of optical fiber ribbon successively stacked to form an optical fiber ribbon stack;
- cushioning fillers made of stack of strings or yarns and disposed so as to surround said optical fiber ribbon stack;
- and
- an outer tube forming a cylindrical inner space so as to surround said cushioning fillers,
- wherein a space factor S of said cushioning fillers in a remaining space after removal of said optical fiber ribbon stack from said inner space of said outer tube is set to be in a range of 10% to 60% when the space factor S is given by the following expression:
- S={B/(πr2−A)}×100
- in which A is a total sectional area of said optical fiber ribbon stack, r is the inner radius of said tube, and B is a total sectional area of the cushioning fillers and given by the following expression:
- B=(denier value×total amount of the cushioning fillers)/(9000×specific gravity of the cushioning fillers).
Dependencies are inferred from the claim text.