Optical fiber Fabry-Perot cavities side-polished fibers and related applications
Abstract
Presented in this thesis are optical fiber Fabry-Perot (FP) sensors and side-polished fibers. By vacuum deposition, aluminum films are formed directly onto the single mode fibers to serve as mirrors. FP cavities with Al mirrors are used in the experimental investigations. Typical finesse is about 4. However, finesse as high as 14 has been achieved. The transfer functions and polarization characteristics of single-mode fiber FP cavities are studied. To use optical fiber FP cavities as temperature and stress sensors, ways must be found to discern the direction of the change of the optical path length. Such a scheme has been developed and demonstrated. Theoretical study also shows two polarization modes are supported by FP cavities containing birefringent fibers, and the retardation between two polarization modes is varied when the fiber is stressed laterally. Taking advantage of the stress dependent retardation, optical fiber polarimetric sensors without using analyzers are proposed and demonstrated. The theoretical results are confirmed with the experimental investigations. The main objectives of side-polished fiber research are to develop techniques to form and to characterize low-loss side polished single mode fibers. Theoretical calculations show that the polished surface has to be within 12 to 2 $\mu$m of the core if significant interaction with the fields guided by a single-mode fiber is desired. The study also reveals that the polishing depth must be determined accurately to within fractions of a micron for most applications. Therefore, stringent dimensional control is necessary if the polishing is to be successful. In this thesis, a reliable technique of fabricating side-polished fibers is established. Single mode fibers are embedded in the V grooves of silicon wafers and polished with 0.05 $\mu$m colloidal silica slurries. A nondestructive method to estimate the polishing depth has been demonstrated.
Degree
Ph.D.
Advisors
Chen, Purdue University.
Subject Area
Electrical engineering
Off-Campus Purdue Users:
To access this dissertation, please log in to our
proxy server.