A digital liquid level transducer based on optical fiber

The paper proposes a digital level transducer based on an optical fiber from which the cladding was removed in n zones at fixed distances from one another. A theoretical analysis of the propagation in this type of modified fiber was carried out, highlighting the good potentiality of the proposed sensor. A 1 m full-scale, 25 mm resolution prototype was then designed using the results of a numerical simulation, and set up by optimizing both the sensing element and the conditioning hardware. The static and dynamic characterization tests carried out show high repeatability, good accuracy, and acceptable dynamic performance.