Fiber optic fluorescence temperature sensors using up-conversion from rare-earth polymer composites.

We demonstrate an optical fiber sensor based on the green up-conversion emission of rare-earth active ions hosted by a polymer matrix. The temperature sensitive composite material is fabricated by simple mixing of the rare-earth ions in powder form (NaYYbErF) with the polymer (polydimethylsiloxane). This fluorescent material is then incorporated on the tip of silica-glass optical fibers to obtain a point temperature sensor probe.