Measurement sensitivity characteristics investigation of an optical fiber sagnac interferometer through strain sensing

Abstract

This report encloses the author’s attempts in the investigation of the measurement sensitivity characteristics of an Optical Fiber Sagnac Interferometer (OFSI) through strain sensing. As many literatures have shown that OFSIs are extensively investigated for various sensing applications, efforts were put in to theoretically analyze and experimentally verify certain parameters. The parameters used are to realize how the optical phase difference of the Sagnac loop would affect the measurement sensitivity characteristics of the OFSI as defined through the birefringence and length of the optical fiber, along with the fringe order of the interference transmission spectra.

Several sets of OFSIs were configured and strain sensing was carried out to determine the sensitivity characteristics of each OFSI. Experimental data of each experiment were stored in a portable storage device and stringently analyzed through the plotting of graphs using the data points generated. Mathematical calculations were performed to study and compare the results of each graph to gain an understanding and realize the sensitivity characteristics of an OFSI.

This report concludes with the achieved objectives of this final year project. Each theoretical parameter and predictions were well-supported by the experimental results. In addition, the experience and understanding of the OFSI the author gained through research and the hands-on experiments of this final year project, as well as future directions are also included.