公开(公告)号：US20170350735A1

公开(公告)日：2017-12-07

申请号：US15538789

申请日：2015-12-23

申请人： Nederlandse Organisatie voor toegepast-natuurwetenschappelijk onderzoek TNO

发明人： Lun Kai CHENG ,  Erwin Johannes Martinus GILING

IPC分类号： G01D5/353

CPC分类号： G01D5/35358 ,  G01D5/35329

摘要： Local strain and optionally other properties of an optical sensing fiber are detected as a function of position along the optical sensing fiber. A light pulse with a plurality of simultaneous laser modes at mutually different wavelengths is transmitted into the optical sensing fiber. Light produced by backscattering of the light pulse in the optical fiber is fed to a multi-way coupler, via a first and second optical path with different optical path lengths. Intensities of different phase combinations of light from the paths are detected by detectors at the outputs of the multiway coupler. A data processing system computes relative phase values of light from the first and second paths for a series to time points with time delays corresponding to scattering at different positions along the fiber. In an embodiment, inelastically scattered light such as due to Brillouin scattering and/or Raman scattered light is selective passed to the detectors and detected.