Zhu Zongda, Liu Lu, Liu Zhihai, Zhang Yu, Zhang Yaxun
Opt Lett. 2017 May 15;42(10):1982-1985. doi: 10.1364/OL.42.001982.
We propose and demonstrate a novel optical-fiber micro-displacement sensor based on surface plasmon resonance (SPR) by fabricating a Kretschmann configuration on graded-index multimode fiber (GIMMF). We employ a single-mode fiber to change the radial position of the incident beam as the displacement. In the GIMMF, the angle between the light beam and fiber axis, which is closely related to the resonance angle, is changed by the displacement; thus, the resonance wavelength of the fiber SPR shifts. This micro-displacement fiber sensor has a wide detection range of 0-25 μm, a high sensitivity with maximum up to 10.32 nm/μm, and a nanometer resolution with minimum to 2 nm, which transcends almost all of other optical-fiber micro-displacement sensors. In addition, we also research that increasing the fiber polishing angle or medium refractive index can improve the sensitivity. This micro-displacement sensor will have a great significance in many industrial applications and provide a neoteric, rapid, and accurate optical measurement method in micro-displacement.
我们通过在渐变折射率多模光纤（GIMMF）上制作Kretschmann结构，提出并演示了一种基于表面等离子体共振（SPR）的新型光纤微位移传感器。我们采用单模光纤来改变入射光束的径向位置作为位移。在GIMMF中，光束与光纤轴之间的角度与共振角密切相关，该角度会因位移而改变；因此，光纤SPR的共振波长会发生偏移。这种微位移光纤传感器具有0 - 25μm的宽检测范围、高达10.32nm/μm的高灵敏度以及低至2nm的纳米分辨率，几乎超越了所有其他光纤微位移传感器。此外，我们还研究发现增加光纤抛光角度或介质折射率可以提高灵敏度。这种微位移传感器在许多工业应用中将具有重要意义，并为微位移提供一种新颖、快速且准确的光学测量方法。
