Etched and Nanocoated SMS Fiber Sensor for Detection of Salinity Concentration
Cardona-Maya, Y.;Villar, Ignacio Del;Socorro, Abian Bentor;Corres, Jesus Maria;Arregui, Francisco Javier;Botero-Cadavid, J. F.;
proceedings2017Vol. 1pp. 333-
282
cardonamaya2017etchedproceedings
Abstract
An optical fibre refractometer has been developed by etching and deposition of a thin film of indium tin oxide (ITO) on a single-mode-multimode-single-mode (SMS) fibre structure. The interference between modes in this structure is sensitive to the refractive index changes of the surrounding medium, achieving sensitivities of up to 7000 nm/RIU in the 1.333–1.338 RIU range. A salinity sensor has been implemented as a practical application of this proposed structure. Fast Fourier transform (FFT) analysis and tracking of an interference dip were used to monitor the interference between modes obtaining sensitivities of 0.99 nm/PSU and 0.025 rad/PSU, respectively.