Optical sensor based on difracu00c7u00c3o networks for monitoring of temperature, relative humidity and ethanol level

摘要

Temperature sensor, relative humidity and ethanol based on Bragg gratings (20) recorded in the optical fiber (30) associated with a coating (10) of an organic - inorganic hybrid material.Organic - inorganic hybrid material provides ease and low processing cost, improved interaction with the optical fiber due to the presence of a skeleton inorganic based su00cdlica, providing greater sensitivity and efficiency, so that the coating is select transducer Ivo in the monitoring of relative humidity or ethanol.The organic - inorganic hybrid material acts as a transducer to absorb water, because volumetricamente dilates or ethanol. This variation of volume induces a disorder (elongamento) in the optical fiber which causes a displacement of the spectrum reflected by the Bragg grating.The monitoring of ethanol in the liquid phase or vapor is particularly useful in industrial areas for the production of ethanol, water transport or even the qualitative determination of alcohol in mixtures containing water.