LOW COHERENT REFLECTOMETER

摘要

PROBLEM TO BE SOLVED: To provide a low coherent reflectometer with high spatial resolution capable of keeping the high spatial resolution even in the case a spatial optical path length of a local emission light is varied. SOLUTION: A low coherent light from a low coherent light source 1 branches away at an optical coupler 3, and one branching light is emitted as a measuring light toward an optical circuit 6 to be measured through a dispersion-shifted fiber 5. The optical coupler 3 also emits another branching light toward a reflective mirror 9 as a local emission light KL. Then, the optical coupler 3 combines a reflecting light RL reflected at a reflection point of the optical circuit 6 to be measured and the local emission light KL reflected by the reflective mirror 9. The optical path length of the dispersion-shifted fiber 5 is set so as to be approximately equal to the length of an optical path that is the distance the local emission light propagates in the space.