Optical fiber sensor and optical fiber sensor multi-point measurement system

摘要

PROBLEM TO BE SOLVED: To provide an optical fiber sensor, using a small and cheap bending type optical fiber which is hardly affected by temperature and is capable of measuring physical quantities such as strain, force, stress, displacement, etc., and an optical fiber sensor multiple point measuring system, capable of multiple point measurement of strain and the like by using the optical fiber sensors and use the system for detecting danger such as caving-in and collapse in a tunnel. ;SOLUTION: An optical fiber type strain gauge 1 has a gauge base 10, having on the whole a square shape formed by an H-shape space 13, a first groove 12 and a second groove 14 formed almost linearly without eccentricity, by providing a specific interval G in the H-shape space 13 along the longitudinal direction of the gauge base 10 and an optical fiber 16 arranged in the first and the second grooves 12 and 14 and having a bend part 16A in the interval G. The width dimensions of the first and the second grooves 12 and 14 are formed 3.2 times as large as the outer diameter dimension(d) of the optical fiber.;COPYRIGHT: (C)2001,JPO