MULTIPLE BEDIG FIBER SESOR FOR MEASUREMET OF LIQUID LEVEL.

In this paper we present a liquid level sensor based on multiple curves, U-shaped, using a single plastic optical fiber. In each of the curvatures of the fiber has a polished side of the region corresponding to the transition losses affecting the cladding and core of the fiber. This action increases the propagation loss but improves the sensitivity of the sensor. Using an 8 mm radius of curvature generated about 1dB loss in the fiber than 1 mm in diameter. With the polished side the transition region at an angle of inclination of 70 º to the axis of the fiber, corresponding to approximately the critical angle of the fiber, the losses increase by 0.1 dB when in contact with air and 0.4 dB when in contact with water. We present experimental results of 16 measurement points, each separated by 1.5 m, between air and water. [ABSTRACT FROM AUTHOR]