OPTICAL FIBER DISTRIBUTED SENSOR AND OPTICAL FIBER DISTRIBUTED SENSING METHOD

摘要

PPROBLEM TO BE SOLVED: To improve the efficiency of a temperature distribution measurement or a strain distribution measurement. PSOLUTION: An optical fiber distributed sensor 1 is provided, wherein probe light and pump light which are output from a light source 14, enter an optical fiber 11 in the normal direction which is set to an object to be measured M, and a BGS of the probe light gained by Brillouin scattering light generated in the optical fiber 11 is measured by a spectrum measuring section 18. When a temperature change or a strain change occurs in a portion of the object to be measured, and its location is sensed, the length of a segment generating the BGS is set shorter by a segment control section 13. Accordingly, the BGS can be generated at a finer spacing near the location where the temperature change or the strain change occurs. Consequently, the location where the temperature change or the strain change occurs, can be specified precisely. If no temperature change nor strain change is sensed, the measurement is carried out with comparatively low accuracy, thereby enabling the measurement time to be shortened. PCOPYRIGHT: (C)2008,JPO&INPIT