Temperature measurement by multifiber optical sensor

The paper deals with a new multifiber temperature sensor, based on the relationship between temperature and the refractive index of a suitable reference liquid, which replaces a part of the fiber cladding. The sensing element, the microcontroller-based hardware, and the artificial neural network (ANN)-based measurement software are described. The results of the tests carried out in the range 40°C-110°C showed good prototype accuracy and repeatability (both contained within ±0.5°C)