[8p-Z19-1~24] 3.8 Optical measurement, instrumentation, and sensor

△ [8p-Z19-22] Measurement method of spatial distribution of birefringence in optical fibers by coherent heterodyne detection

〇(M1C)Nanako Takei¹, Shiro Ryu¹ (1.Meiji Univ.)

Keywords:optical fiber, birefringence, local birefringence

The coherent heterodyne detection technique can directly observe the phase information of light inside the optical fiber. We have shown that this technique can be used to observe backscattered light in an optical fiber and measure the distribution of optical fiber birefringence in the longitudinal direction of the fiber. In this paper, the above measurement method is extended to measure the local birefringence of an optical fiber. In the conventional method using POTDR, it took time to measure the local birefringence, but this method can be measured in a short time of about 1 ms.