US 4,729,627 A · Optical fiber cable for detecting low temperature

Abstract

An optical fiber cable for detecting a low temperature comprising a center member made of a material having a low coefficient of linear expansion and one or more longitudinally extending grooves in each of which at least one optical fiber is placed, (i) wherein at least one optical fiber comprising a core and a cladding both made of silica glass is placed in each of said grooves and the interior space of the groove which is not occupied by the optical fiber or fibers may be filled with a resin which has a low glass transition temperature; or (ii) wherein each of the optical fibers placed in each of said grooves, have different coating structures from each other and/or different fiber structures from each other so as to detect a low temperature in different temperature ranges.

Claims14

Dependent claims

An optical fiber cable for detecting a low temperature, comprising:

a center member having a longitudinally extending groove in the outer surface thereof, said center member being made of a material having a low coefficient of linear expansion;
an optical fiber, contained in said groove, said optical fiber including a core and a cladding about said core, both said core and said cladding being made of silica glass;
a resin having a low glass transition temperature filling in the interior space of said groove not occupied by said optical fiber, said resin being in direct contact with said cladding such that changes in the physical properties of the resin due to temperature induce microbending in the optical fiber, thereby altering optical characteristics of said fiber;
and
a protective covering surrounding the periphery of said center member containing said optical fiber and said resin.

2 more elements

Dependencies are inferred from the claim text.

Optical fiber cable for detecting low temperature

Life of this patent

Optical fiber cable for detecting low temperature

Life of this patent

Abstract

Claims14