Novel Fiber-Optical Refractometric Sensor Employing Hemispherically-Shaped Detection Element
We present the theoretical and experimental data on the performance of the novel fiber-optic refractometric sensor that employs the hemispherical optical detection element. We exploit the sensitivity of internal reflection of light on the element’s spherical surface to the refractive index of the surrounding medium, several internal reflections in series, and the focussing properties of the concave spherical surface to achieve the enhanced sensitivity and reduce the intrinsic optical loss in the sensor. We show that the transmission function of the new sensor can easily be modified in the wide interval of the refractive index of the surrounding medium. This new sensor may find applications in different instruments. Key-Words:Optoelectronics, instrumentation, refractive index measurement, liquid level measurement.
A Prototype Fiber-Optic Discrete Level-Sensor for Liquid Propane-Butane
This paper describes a fiber-optic level sensor designed to measure the level of liquid propane-butane in a relatively short range (60 cm) in the top part of storage tanks at oil refineries with the purpose of monitoring the level of this product in the filled or slightly underfilled or overfilled tanks during various measuring operations. A discrete multi-element device employing novel refractometric transducers was selected because it yields both a large measurement range and high resolution. Several innovations offer a competitive advantage to industrial users: 1) Special micro-optical refractometric transducer; 2) Efficient and economical sensor multiplexing scheme; 3) Fast leveltracking operational algorithm. The vertical resolution of the sensor −1 cm, the maximum excess pressure in the tank −40 atm (4 MPa). The sensor has the spark-proof and explosion-proof design and optical fiber interface for the transmission of the output data. The sensor successfully measured liquid propane-butane level in storage tanks during numerous cycles of measuring operations. key words: liquid level measurement, ber-optic sensor, liquid
FIBER SENSORS FOR INDUSTRIAL APPLICATIONS
Since 1983, BERTIN & Cie is involved into the development of fiber optic sensors which meet such requirements for many customers and this paper aims at providing with a description of some practical achievements in various industrial areas, like petroleum industry, water resources management, energy production or space and aeronautics. Intentionally, we have chosen to pass over the fields of energy transportation (current and voltage sensors) as well as aeronautics and civil engineering structure monitoring, since dedicated invited papers are devoted during this conference to the reviewing of such applications.