RT Journal Article T1 A fibre-optic temperature sensor based on the deposition of a thermochromic material on an adiabatic taper A1 Díaz Herrera, Natalia A1 Navarrete Fernández, María Cruz A1 Esteban Martínez, Óscar A1 González Cano, Agustín AB A fibre-optic sensor has been developed for the measurement of temperature, especially of liquids. The device is conceived as part of an all-optical CTD probe for the control of the physical parameters of a marine medium. The dependence on temperature of the optical properties (specifically, absorbance) of a thermochromic material, namely lophine (2,4,5-triphenylimidazole), is the basis of the sensor. The sensor presents some significant differences with respect to other similar sensors proposed in the literature: the use of adiabatic, long, tapered optical fibres with adjustable geometric parameters; the use of LED illumination in the 800 nm range; improvements in the deposition technique, etc. The sensors show a linear behaviour over the desired temperature range, and their sensitivity is high. Also, the dependence of the response of the sensor with variations of the geometry of the tapers is discussed. Specifically, we have performed measurements with different diameters of the taper waist, and we show the dependence of the slope of the response curve with that parameter. PB IOP Publishing Ltd. SN 0957-0233 YR 2004 FD 2004-02 LK https://hdl.handle.net/20.500.14352/50968 UL https://hdl.handle.net/20.500.14352/50968 LA eng NO [1] Esteban Ó, Navarrete M C, González-Cano A and Bernabeu E 1999 Measurement of the degree of salinity of water with a fiber-optic sensor Appl. 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Lett. 77 1654-6 NO © 2004 IOP Publishing Ltd.This work has been partially supported by European Project MISPEC, contract number EVK3-CT2000-00519 and Spanish Project OPTIMA, Programa Nacional de Recursos Naturales, MCYT, ref. REN2001-1495. We are indebted to C. Fernández-Valdivielso, F J Arregui and I. Matías of the Universidad Pública de Navarra (Spain) for their help and support. NO European Union NO Ministerio de Ciencia y Tecnología (MCYT), España DS Docta Complutense RD 29 abr 2024