Abstract
There have been many studies on model characteristics of optical fibers since 1970. In the past twenty years we have seen changes in the index profiles and operating parameters (such as the carrier wavelength and fiber dispersion) of the fibers. We shall expect some change in the future as well. In this thesis we propose a 2nd-order coupled transverse magnetic field ordinary differential equations and associated boundary conditions for analyzing fiber modes with complex index profiles. Using finite-difference approximation, we convert the equations into matrix eigenvalue-eigenvector equations. These are then numerical solved (suing many commercial numerical softwares such as Matlab) to obtain propagation constants and field distribution inside the fibers.
We shall show that our method do not require the use of cylindrical functions nor will the computation increase due to the increase of complexity in the index profile. In addition to finite-difference approximation, we may expand the model solutions in terms of elementary functions. In this thesis we computed many commercially available optical fibers such as 8/125, 9/125 step index fibers and 50/125, 62.5/125 graded index fibers. We compared our results against exact solution (the step index case) and found that we have converging solutions as we reduce the fiber sampling grid size £Gx. The difference in propagation constant is less than 0.1% when £Gx is < £f/6 .
| Identifer | oai:union.ndltd.org:NSYSU/oai:NSYSU:etd-0703102-204632 |
| Date | 03 July 2002 |
| Creators | Fang, Ching-Wei |
| Contributors | none, none, none, Hung-Wen Chang |
| Publisher | NSYSU |
| Source Sets | NSYSU Electronic Thesis and Dissertation Archive |
| Language | Cholon |
| Detected Language | English |
| Type | text |
| Format | application/pdf |
| Source | http://etd.lib.nsysu.edu.tw/ETD-db/ETD-search/view_etd?URN=etd-0703102-204632 |
| Rights | withheld, Copyright information available at source archive |
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