Nd 3+ -doped optical fiber temperature sensor using the fluorescence intensity ratio technique

An optical fiber temperature sensor employing the fluorescence intensity ratio using ${\mathrm{Nd}}^{\mathrm{3+}}$ -doped silica fiber and exhibiting high sensitivity is presented. The development and construction of the sensor, which requires relatively simple electronics and data analysis, is described together with its calibration over the −50 to +500 °C temperature range.