STRAIN ISOLATED OPTICAL FIBER BRAGG GRATING SENSOR

摘要

PROBLEM TO BE SOLVED: To provide an optical fiber Bragg grating sensor that isolates a strain and is capable of being used to correct a change of a similar non-strain isolated optical fiber Bragg grating sensor affected by a temperature. SOLUTION: A sensor 1 has an optical fiber 2 with a Bragg grating 3 provided at one end 2a thereof. A cap 4 surrounds the end 2a of the optical fiber 2 and the circumference of the Bragg grating by taking a space from the optical fiber, fiber end and Bragg grating so as not to contact thereto directly. The cap 4 is sealed to the fiber 2 at an opening at a side of the Bragg grating away from the optical fiber 2. The cap 4 is made from a material having a low Young's modulus and is operable to isolate the Bragg grating 3 from strain.