Statkiewicz-Barabach G, Carvalho J P, Frazão O, Olszewski J, Mergo P, Santos J L, Urbanczyk W
Wroclaw University of Technology, Institute of Physics, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw, Poland.
Appl Opt. 2011 Jul 20;50(21):3742-9. doi: 10.1364/AO.50.003742.
We present a compact in-line fiber interferometric sensor fabricated in a boron doped two-mode highly birefringent microstructured fiber using a CO(2) laser. The intermodal interference arises at the fiber output due to coupling between the fundamental and the first order modes occurring at two fiber tapers distant by a few millimeters. The visibility of intermodal interference fringes is modulated by a polarimetric differential signal and varies in response to measurand changes. The proposed interferometer was tested for measurements of the strain and temperature, respectively, in the range of 20-700 °C and 0-17 mstrain. The sensitivity coefficients corresponding to fringe displacement and contrast variations are equal respectively for strain -2.51 nm/mstrain and -0.0256 1/mstrain and for temperature 16.7 pm/°C and 5.74×10(-5) 1/°C. This allows for simultaneous measurements of the two parameters by interrogation of the visibility and the displacement of interference fringes.
我们展示了一种紧凑的在线光纤干涉传感器，它是使用二氧化碳激光在掺硼双模高双折射微结构光纤中制造的。由于在相距几毫米的两个光纤锥处发生的基模和一阶模之间的耦合，在光纤输出端出现了模间干涉。模间干涉条纹的可见度由偏振差分信号调制，并随被测量的变化而变化。所提出的干涉仪分别在20 - 700°C和0 - 17 m应变的范围内进行了应变和温度测量测试。对应于条纹位移和对比度变化的灵敏度系数分别为：应变时为-2.51 nm/m应变和-0.0256 1/m应变，温度时为16.7 pm/°C和5.74×10(-5) 1/°C。这使得通过询问干涉条纹的可见度和位移能够同时测量这两个参数。
