基于游标效应的级联腔法布里-珀罗干涉型气体压力传感器。

Cascaded-Cavity Fabry-Perot Interferometric Gas Pressure Sensor based on Vernier Effect.

机构信息

National Engineering Laboratory for Fiber Optic Sensing Technology, Wuhan University of Technology, Luoshi Road 122, Wuhan 430070, China.

出版信息

Sensors (Basel). 2018 Oct 29;18(11):3677. doi: 10.3390/s18113677.

An extrinsic Fabry-Perot interferometer (EFPI) composed of double fiber FP cavities in a glass capillary tube to generate Vernier effect has been fabricated and employed for gas pressure sensing. A lead-in single-mode fiber (LSMF) and a reflective single-mode fiber (RSMF) were inserted into the capillary tube to form a FP cavity. Femtosecond (fs) laser was used to ablate openings on a capillary tube for gas passage to the FP cavity. A fusion hole was also drilled on the end face of a SMF by fs laser. The sensitivity of the sensor is enhanced due to Vernier effect. Experimental results show that the sensitivity was as high as 86.64 nm/MPa in the range of 0~0.6 MPa, which is 32.8 times larger than that of an open-cavity EFPI sensor without Vernier effect. The temperature cross-sensitivity of the sensor was measured to be about 5.18 KPa/°C. The proposed sensor was characterized by its high sensitivity, compact structure and ease of fabrication, and would have extensive application prospects in gas sensing fields.

一种由玻璃毛细管中双光纤法布里-珀罗（FP）腔构成的外差法布里-珀罗干涉仪（EFPI），用于产生游标效应，可用于气体压力传感。将一根单模光纤（LSMF）和一根反射单模光纤（RSMF）插入毛细管中，形成一个 FP 腔。飞秒（fs）激光用于在毛细管上烧蚀开口，以便气体进入 FP 腔。通过 fs 激光在 SMF 的端面上也钻了一个熔接孔。由于游标效应，传感器的灵敏度得到了提高。实验结果表明，在 0~0.6 MPa 的范围内，传感器的灵敏度高达 86.64nm/MPa，比没有游标效应的开腔 EFPI 传感器的灵敏度高 32.8 倍。测量了传感器的温度交叉灵敏度，约为 5.18kPa/°C。该传感器具有灵敏度高、结构紧凑、易于制造等特点，在气体传感领域具有广阔的应用前景。