ASSESSMENT OF METROLOGICAL PARAMETERS BY MEANS OF FIBER-OPTIC SENSORS

Abstract

Fiber-optic sensors will get their share of the sensor market only if they can be made available at low prices or if they can solve metrological problems that have no suitable solutions within conventional sensor techniques. Since fiber-optic components are in general still high cost items, fiber-optic sensors are not likely to become competitive in this respect within the near future. These sensors do provide, however, important specific advantages such as isolation against high voltage, immunity against electromagnetic fields as well as explosive and/or corrosive environments, possibility of miniaturized and compact packaging of the sensing element, and application within a broad temperature range. Multimode fiber-optic sensors for parameters such as temperature, pressure, level , and refractive index are on the market already or very close to being commercialized. Monomode fiber-optic sensors are not yet on the market due to their more demanding technology and the corresponding higher cost level . They are expected, however to provide at acceptable costs in a forseeable future high precision solutions for metrological tasks under specific conditions (e.g. Sagnac gyroscopes, hydrophones, temperature measurement in a microwave field).