Patent ID: 7997792
Filing Date: 2011-08-16
Classification: G01K

Abstract:
1. An optical fiber temperature sensor, comprising: an optical fiber including a first domain installed in an object, and a second domain set as a specified temperature; an optical frequency difference adjusting section for sweeping a difference between each center frequency of probe light and pumping light to be inputted into the optical fiber; a light source system for outputting the probe light into one end of the optical fiber, while outputting the pumping light into the other end of the optical fiber, each center frequency of the probe light and the pumping light being set by an indication of the optical frequency difference adjusting section; a spectrum measuring section for receiving, as an outputted light from the optical fiber, the probe light having acquired a gain by Brillouin scattering generated with propagation of the probe light and the pumping light from the light source system, and for measuring data relevant to a shape of a Brillouin gain spectrum, the Brillouin gain spectrum being the spectrum of the gain acquired by the received probe light by the Brillouin scattering; a temperature calculating section for computing a temperature distribution of the first domain in the optical fiber based on a measurement data relevant to the shape of the Brillouin gain spectrum of the first domain measured by the spectrum measuring section; and a correcting section for instructing correction of at least one of optical frequencies of the pumping light and the probe light outputted to the optical fiber to the light source system so as to make known reference data relevant to the shape of the Brillouin gain spectrum set up in advance as the reference value of the Brillouin gain spectrum of the second domain at the specified temperature be in agreement with the measurement data relevant to the shape of the Brillouin gain spectrum of the second domain.