光纤陀螺用保偏光纤温度敏感性测试与分析

摘要

针对高精度光纤陀螺的温度敏感性问题，重点研究了光纤陀螺用保偏光纤温度性能。利用具有高空间分辨率的脉冲预泵浦光时域分析技术，测量不同温度点光纤的长度变化量，再根据光纤长度随温度的变化量与折射率温度系数的关系，给出光纤的折射率温度系数。试验共测量了8种国内和国外主流保偏光纤的折射率温度系数，测试结果显示：8种光纤折射率温度系数的最大值与最小值之间相差14％；某型国内保偏光纤与某型国外保偏光纤的折射率温度系数最小，量值基本相同。这种不同类型的保偏光纤折射率温度系数的差异与光纤纤芯的掺杂元素及掺杂浓度是直接相关的。该项测试技术可在基础材料层面提升光纤陀螺的温度性能；通过折射率温度系数测试，优恒出更加适用于光纤环圈制作的保偏光纤，从而减小光纤陀螺温度Shupe效应误差，对于提高光纤陀螺的温度性能具有重要意义。%In view of the problem of temperature sensitivity in high-precision fiber optic gyroscope(FOG), the temperature performance of polarization maintaining fiber for FOG is studied. By using the pulse pre-pump Brillouin optical time domain analysis with high spatial resolution, the length variation of fiber in different temperature can be measured, then the temperature coefficient of refractive index of fiber can be obtained. Eight kinds of polarization maintaining fibers for FOG were measured. There is a difference of 14% between the maximum and minimum temperature coefficients of refractive index, in which the temperature coefficient of refractive index of a foreign polarization maintaining fiber is the smallest. The difference between temperature coefficients of refractive index is directly related to the doping elements and concentration. This technology can be used to improve the temperature performance of FOG by testing the temperature coefficient of refractive index to select more suitable polarization maintaining fiber for optical fiber coil and thereby reduce the Shupe effect error of FOG.