Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1987 · 33 citations · 0 references
EngineeringChemical EngineeringMaterials ScienceOptical MaterialsPhotonicsSensorsChemical SensorsFiber OpticsOptical FibersOptical SensingOptical SensorsRefractive IndexChemical Optical SensorsFiber SensorsFiber-optic SensingFiber-optic SensorsOptical Chemical SensingOptical Fiber SensorsSingle-mode FibersSingle-mode Optical Fibers
Fiber Optic intensity sensors based on the interaction between an external medium and t he evanescent wave of unclad and tapered multimode and single mode fibers have been developed to measure refractive index, temperature and liquid level. Here we describe an intensity bio-chemical fiber optic sensor (BCFOS) where absorption of t he evanescent wave by a dye-labeled solution is used to modulate, attenuate, t he intensity of t he signal in t he core of the fiber. The fabrication and performance is described for laboratory prototype sensors using etched multimode and tapered single mode fibers.