Analysis and measurement of macrobend losses and retardance in single-mode optical fiber.

摘要

In this thesis macrobend losses and retardance suffered by a Single mode optical fiber due to application of pressure are analyzed. This study attempts to pave way for usage of normal fiber in polarimetric sensors, which utilize the State of Polarization of light due to measurand as transduction mechanism. Hence polarization effects, mode coupling and losses of the fiber are analyzed theoretically and experimentally.; The experimental set up presented here consists of a Single-Mode Fiber bend at its radius of curvature acting as a pressure sensing device. The end of the fiber is connected to a Polarization Analyzer, which records the Retardance variation and power output of the sensor. The bent fiber is exposed to varying pressure to observe the polarization effects and the mode coupling capabilities of the fibers.; Theoretical and Experimental analysis reveals that in this set up the fiber has good polarization capability and negligible mode coupling effects. This clearly shows that this set up in future could be utilized as a polarimetric pressure sensor. Finally, the theoretical and experimental data are compared with each other and a correction factor for the theoretical values is obtained.