High temperature sensing characteristics of erbium-doped fiber using fluorescence intensity ratio technology

The fluorescence intensity ratio (FIR) technique for optical fiber-based temperature sensing is discussed in many previous papers. But in the high temperature sensing the FIR technique has been researched a little. In this paper, the temperature dependence of fluorescence in erbium-doped fiber between ∼700 and ∼1300°C is discussed and experimentally demonstrated. 1450nm and 1530nm wavelengths are chosen to calculate the FIR, and the temperature coefficient could achieve ∼ 0.003dB/°C.