Method and apparatus which for safety applications reflection measurement of optical polarized waves used in the time domain

摘要

A preferred apparatus and methods are, in which a distributed light waves sensor is used, a disturbance along its length in order to detect. A pulse of polarized light is s into an optical fiber; during the progress of the pulse along the optical fiber by rayleigh loses surface backscatter continuously a small amount of its energy. The rayleigh scattering light is surface feedback by means of a polarisation sensitive element, such as a light fibers - polarizer, is analyzed. The dynamics of the time dependency of the polarization of the analyzed, back-scattered light is used in order to determine whether a disturbance along the light fibers piece has been present. This technique can be used in areas of application, such as optical fiber, - telecommunication, precaution zone, fire and pipelines.