الفهرس | Only 14 pages are availabe for public view |
Abstract The present study aims to investigate polarization maintaining (PM) optical fibres using optical interference methods. A historical introduction was presented in the first chapter on fibre optics in general, and specifically on PM optical fibres. The historical overview dealt with the developments in the methods and applications of optical interference since 1952. We highlighted the evolution of the methods of calculating the refractive index of optical fibers since 1974 until now. In the second chapter, a theoretical model was developed to measure the refractive index of PM optical fibres based on the sample cross-section image. This theoretical model was programmed using the Matlab programming environment. This model enables us to obtain the optical phase difference (theoretically). Another program was developed to identify the phase difference (experimentally) by analyzing the interference images. Connecting the two programs, we were able to compare the experimental and theoretical phases effectively and quickly. The experimental techniques, discussion and demonstration of the results were presented in chapter three. An experimental technique for obtaining the cross-sectional images of PM optical fibres was described. The two-beam Mach-Zehnder interference system was introduced and used in the study of two types of PM fibres PANDA and Bow-tie samples. Feeding the previously developed program by the cross-sectional interference images, we were able to compare the experimental and theoretical phase differences. The refractive indices were changed until the phase differences become in coincidence, and then the refractive index values for each sample were retrieved. All other parameters corresponds to refractive index were also calculated for each sample. The calculated values were compared with the values given by the fibre manufacturer and the published ones. |