Strain independence of the fluorescence intensity ratio temperature sensing technique in neodymium-doped optical fiber

The effect of strain on the fluorescence intensity ratio technique has been investigated using Nd3-doped fibre as the sensing material. Measurements of the fluorescence intensity ratio for applied strain values up to approximately 2000 show a relatively small sensitivity of (1.5 1.4) x lO %/is while the temperature sensitivity was found to be 1.56 %/°C. This implies a strain-temperature cross-sensitivity of(1.O 0.9) x 1O °C/p., ie. an applied strain of 1000 would induce errors ofonly 0.10 0.09 °C.