Wu Yongfeng, Zhang Yundong, Wu Jing, Yuan Ping
Opt Express. 2017 Apr 17;25(8):9443-9448. doi: 10.1364/OE.25.009443.
We experimentally demonstrate transverse load and strain sensing based on a fiber optic Fabry-Perot interferometer (FPI) with special air cavity, which was created by fusion splicing single mode fiber (SMF), hollow core fiber (HCF) and several electrical arc discharges. The cavity height of this structure is higher than the cladding diameter of SMF so that it can sense transverse load with high sensitivity. The transverse load sensitivity of this air cavity FPI sensor is 1.31 nm∕N and about 5 times more sensitive compared to the current fiber tip interferometer (0.2526 nm∕N). Meanwhile, this sensor also can measure strain and the strain sensitivity of 3.29 pm∕με is achieved. In addition, the low temperature sensitivity (1.08 pm/°C) of the sensor can reduce the temperature-induced measurement error. This novel air cavity FPI can be developed and used as high-sensitivity transverse load and strain sensor with temperature-insensitive.
我们通过实验证明了基于具有特殊空气腔的光纤法布里-珀罗干涉仪（FPI）的横向负载和应变传感，该空气腔由单模光纤（SMF）、空心光纤（HCF）的熔接以及多次电弧放电形成。这种结构的腔高高于单模光纤的包层直径，因此它能够以高灵敏度感知横向负载。这种空气腔FPI传感器的横向负载灵敏度为1.31 nm∕N，与当前的光纤尖端干涉仪（0.2526 nm∕N）相比，灵敏度约高5倍。同时，该传感器还能测量应变，实现了3.29 pm∕με的应变灵敏度。此外，该传感器的低温灵敏度（1.08 pm/°C）可减少温度引起的测量误差。这种新型空气腔FPI可被开发并用作对温度不敏感的高灵敏度横向负载和应变传感器。
