光纤布拉格光栅温度灵敏性的实验研究

Experimental investigation on temperature sensitivity of fiber Bragg gratings

在-150～550℃的温度范围内测量了光纤布拉格光栅中心反射波长的温度灵敏性。光栅波长的温度响应是非线性的。通过对试验数据的三次多项式进行拟合分析,结果表明:波长为1500nm左右的光栅具有相同的温度敏感性;波长对温度变化的响应(ΔλB/ΔT)主要是由折射率的变化(dn/dT)引起的,dn/dT随着温度的降低而减小;得到了温度灵敏系数关于温度的二次表达式,并给出了在-150～550℃温度范围内波长变化的快速估算。

The temperature dependence of the reflection wavelength of fiber Bragg gratings was measured at -150～550℃. The non-linear temperature dependence of the Bragg graings wavelength was demonstrated. Three-order polynomial curves were used to fit the experimental data. The result shows that the Bragg gratings with about 1500nm wavelength have the same temperature sensitivity. The wavelength dependence reflection （△λB/△T） corresponds to the refractive index dependence （dn/dT）, dn/dT decreases with lower temperature. The function of second degree of temperature sensitivity coefficient is obtained. The rapid estimative value for wavelength shift at -150～550℃ is provided.