POLARIMETRIC FIBER PHOTOSENSOR

摘要

PURPOSE: To find physical phenomenon interfering with an optical fiber in a space by using an optical sensor with a polarization maintaining fiber having light propagation modes. CONSTITUTION: A reference light signal emitted from a light source 10 is propagated to an optical fiber 12 via a light connector 11 and is propagated to an optical fiber 15 via a light connector 14. Power coupling is induced between two propagation modes at a point A of the optical fiber 15 owing to the deformation of the optical fiber determined by a first ring 16. Power coupling is induced again between the two propagation modes due to the deformation of the optical fiber determined by the second ring 16 at a point B of the optical fiber 15, an a second measurement light signal is generated and propagated by the propagation mode of the first measurement light signal at a smaller speed than the propagation speed of a reference light signal. Similarly, another power coupling is induced owing to the deformation of the optical fiber determined by the third ring 16 at a point C of the fiber 15 so that a generated signal is propagated.