high sensitivity optical sensor for fuel adulteration assessment employing long period networks and tuned optical fibers

摘要

High Sensitivity Optical Sensor for Fuel Adulteration Assessment Employing Long Period Networks and Tuned Optical Fibers The present patent application relates to an optical system capable of measuring refractive index variations of high sensitivity liquid solutions. The sensor device is constructed from fiber optics which have their dimensions reduced and which record two long period networks arranged in series. The sensitivity for this device is 22 times higher than the situation where there was no tuned region between the two lpgs in series. The measurement of refractive index variations using optical fibers is very useful in identifying the concentration of a given solute in a given solution of interest. In particular, because optical fibers are electrically passive and represent an alternative to absorption measurements, fiber optic sensors that are based on the interaction of the evanescent field of light with the medium of interest become potentially interesting with respect to fuel monitoring.