Ye Wenhao, Jiang Chao, Guo Xiaoshan, Chen Hailin, Wang Yuan, Zhu Xiping, Sun Simei, Liu Changning
College of Physics and Electronic Science, Hubei Normal University, Huangshi, Hubei 435002, China.
Rev Sci Instrum. 2022 Aug 1;93(8):085002. doi: 10.1063/5.0096163.
In this paper, a highly sensitive optical fiber gas pressure sensor is proposed and experimentally verified. The sensor is composed of two Fabry-Pérot (F-P) cavities, and two F-P cavities are fabricated by a single-mode fiber and two quartz capillaries with different inner diameters splicing. Among them, the small inner diameter capillary is used as a gas channel connecting the large inner diameter capillary and the external environment. The manufacturing process of the sensor only involves capillary cleaver and splicing and does not involve other complex manufacturing technologies. By correctly adjusting the length of the two quartz capillaries, when the free spectral range of the two F-P cavities is very close, the optical Vernier effect will be observed and used as a sensitive probe for detecting gas pressure. The experimental results show that, in the pressure range of 0-0.8 MPa, the gas pressure sensitivity of the sensor reaches -81.73 nm/MPa with a linearity of 99.7%, and the temperature cross-sensitivity is only 1.82 kPa/°C. Due to its easy manufacture, high sensitivity, compact structure, and small volume, the sensor has become one of the preferred structures for large-scale use in the field of gas sensing.
本文提出并通过实验验证了一种高灵敏度光纤气压传感器。该传感器由两个法布里-珀罗（F-P）腔组成，两个F-P腔由一根单模光纤和两根不同内径的石英毛细管拼接而成。其中，小内径毛细管作为连接大内径毛细管与外部环境的气体通道。该传感器的制造过程仅涉及毛细管切割和拼接，不涉及其他复杂制造技术。通过正确调整两根石英毛细管的长度，当两个F-P腔的自由光谱范围非常接近时，将观察到光学游标效应，并将其用作检测气压的灵敏探头。实验结果表明，在0-0.8MPa的压力范围内，该传感器的气压灵敏度达到-81.73nm/MPa，线性度为99.7%，温度交叉灵敏度仅为1.82kPa/°C。由于其易于制造、灵敏度高、结构紧凑、体积小，该传感器已成为气体传感领域大规模应用的首选结构之一。
