Optical fiber humidity sensor based on evanescent-wave scattering

Optical fiber humidity sensor based on evanescent-wave scattering.

The phenomenon of evanescent-wave scattering (EWS) is used to design an optical-fiber humidity sensor. Porous solgel silica (PSGS) coated on the surface of a silica optical-fiber core scatters evanescent waves that penetrate the coating layer. Water molecules in the gas phase surrounding the optical fiber can be absorbed into the inner surface of the pores of the porous silica. The absorbed wat...

Temperature-independent polymer optical fiber evanescent wave sensor

Although the numerous advantages of polymer optical fibers have been exploited in the fields of sensors and telecommunications, such fibers still experience a critical problem: the temperature dependency. Therefore, we explored the temperature-independent operation of a polymer fiber-optic evanescent wave sensor immersed in distilled water. We investigated variations in the surface morphology, ...

Esa Based Fiber Optical Humidity Sensor

Optical Fiber Humidity Sensor Based on Lossy Mode Resonances

A novel optical fiber humidity sensor based on lossy mode resonances (LMR) has been developed. LMRs are supported here by a thin Indium Tin Oxide (ITO) coating fabricated onto an optical fiber core via a sol-gel dip coating. ITO coated optical fiber devices present a resonant maximum absorption peak in the infra-red region which is shifted to higher wavelengths when the refractive index of the ...

Perfluorinated Plastic Optical Fiber Tapers for Evanescent Wave Sensing

In this work we describe the fabrication and the characterization of perfluorinated plastic-cladded optical fiber tapers. The heat-and-pull procedure has been used to fabricate symmetric tapers. Devices with different taper ratio have been produced and the repeatability of the process has been verified. The very low refractive indexes of the core-cladding perfluorinated polymers (n = 1.35-1.34)...