Distortion measuring apparatus and distortion measuring method using this apparatus

摘要

The present invention is provided for obtaining an apparatus and a method for accurately measuring a variation of a distortion of an optical fiber by excluding an apparent variation of the distortion of the optical fiber which is generated by a drift of a BOTDR waveform. The distortion measuring apparatus of the present invention comprises a sensor cable and a reference fiber which is connected with the sensor cable in series. The measured variation of the distortion of the sensor cable is corrected by subtracting the apparent variation of the distortion of the reference fiber from the measured variation of the distortion of the sensor cable. It is preferable that the reference fiber be housed in an thermostatic chamber and temperature of the reference fiber be maintained in a predetermined value within a range of 10 to 40° C. with an error of ±2° C.