报道了利用光纤布拉格光栅反射波谱带宽展宽技术实现温度补偿的压强传感新方案。结合平面圆形膜片应变调谐的特点, 采用膜盒式结构, 将光纤光栅中心对准平面圆形膜片零应变半径并沿径向粘贴, 利用反射波谱带宽对应变敏感而对温度不敏感的特性解调压强, 成功地实现了温度补偿的压强传感测量。基于光谱分析仪0.05 nm的光谱分辨力, 实验测得带宽随压强响应灵敏度为0.34 nm/MPa, 压强精度为±0.15 MPa, 压强测量范围为0～7.5 MPa。实验结果与理论分析基本一致。

A novel temperature-insensitive pressure sensor based on fiber Bragg grating (FBG) broadened bandwidth technique using a plane round metal diaphragm is studied theoretically and experimentally. Considering the strain modulating trait of the diaphragm, the smart box structure is adopted and FBG is affixed radially, with the axis center of FBG aiming at the zero strain zone of the diaphragm. Temperature-independent pressure sensing is measured by bandwidth of FBG due to the bandwidth is sensitive to strain but temperature. This approach shows a pressure resolution of ±0.15 MPa and a pressure sensitivity of 0.34 nm/MPa in the range 0～0.75 MPa, with the spectral resolution of the spectral analyzer of 0.05 nm. The experimental results match the theoretical analysis well.