Patent ID: 7576840

Claim:
A Brillouin spectrum measuring method of measuring a physical amount relating to a measurement target, by utilizing a Brillouin spectrum as a spectrum of Brillouin scattered light that is generated in accordance with an input of pumping light with a predetermined wavelength from inside an optical fiber installed in the vicinity of the measurement target, said method comprising the steps of: preparing an optical fiber section including a first optical fiber and a second optical fiber for which the difference between the peak frequencies of the Brillouin spectra obtained in a predetermined temperature and predetermined strain-applied state for which the respective usage environments are assumed is equal to or more than a predetermined frequency difference, said first and second optical fibers being serially connected via a connection portion; measuring the Brillouin spectrum obtained in accordance with the pump light that is supplied to said optical fiber section; and confirming the point of connection between said first and second optical fibers on the basis of measurement data for the measured Brillouin spectrum.