OpticalFiberSensors

Abstract

PolarizationMaintainingfibers(PMFs)aregainingmoreinterestinfiberopticsensors suchascurrent,rotationrate ... etc aswellashighperformance optical links. Thus accurate hands oncharacterizationofPMFs isrequired forthe evaluationofits per- formance. Optical Coherence Domain Polarimetry(OCDP)isthe main method for measuring not onlythepolarizationmodecouplingdistributedalongPMFs under test but alsothegroupbirefringenceandgroupbirefringencedispersion.

This thesis presents an all PM fiber Michelson interferometerusing singlePM fiber loopmirror (FLM) instead offreespacemirrors forOCDP applications.Thesystemin this thesis offerssimpler setup realization and lowercost compared to freespaceone. ThermalvariationofthetwofiberarmsdelaydifferenceoftheMichelsoninterferometer ispartiallyovercomebyfitting onearm with Piezo-electric fiberstretcherdriven near resonance. TheanalyticalmodelofthePMfiberinterferometerisdevelopedaswellas asetofexperimentalresults todemonstrateitsoperation.

Also, in this thesis an all-fiber OCDP setup isbuilt forpolarizationmode coupling measurementsinPMFs. PMF parameterssuchasgroupbirefringence andgroupbire- fringence dispersion are alsomeasured using the proposed system. The performance limitationsofthe new setup are estimatedtheoreticallyand verified experimentally. The limitationsofthis proposed system aredeviation ofthe splitting ratio ofthe PM couplersfrom50/50 and finitepolarizationextinctionratio (PER)ofthe fibercompo- nentsused.