利用光纤光栅的偏振特性感知外界参量变化是光纤光栅传感的新研究热点。提出利用光纤光栅第一斯托克斯参量s1感知外界压力的新方法。推导了光纤光栅压力所致线双折射和s1参量的关系,建立了压力、线双折射和s1参量三者之间的关系模型,分析了线偏振光入射角度对s1参量的影响。仿真表明,偏振光入射角度影响s1曲线的基准值,同时也影响左右波长测量点的对称性和线性度。利用光纤光栅和高速在线检偏器搭建了实时压力测量系统,测量了不同偏振光入射角度下s1参量受压力所致线双折射的影响曲线,验证了理论仿真结果。 Using the polarization characteristics of fiber gratings to sense the change of external parameters is a new research focus of fiber grating sensing. A new method of sensing external pressure using the first Stokes parameter s1 of fiber grating is proposed. The relationship between the line birefringence and the s1 parameter induced by the fiber grating pressure is deduced. The relationship between the pressure, the line birefringence and the s1 parameter is established. The influence of the incident angle of the linearly polarized light on the s1 parameter is analyzed. The simulation shows that the incident angle of polarized light affects the reference value of s1 curve and affects the symmetry and linearity of the left and right wavelength measurement points. The real-time pressure measurement system was built by using fiber grating and high-speed on-line analyzer. The influence curve of the birefringence of s1 parameter under different incident angle of polarization was measured, and the theoretical simulation results were verified.