We have proposed and experimentally demonstrated a compact strain sensor based on incline plane-shaped long period fiber grating (IPS-LPFG). This asymmetry structure enhances the sensitivity of strain and shortens the length of the sensor. The ultra-high sensitivity of the strain sensor is attributed to the stress micro bending introduced by the asymmetric thickness of the unique incline plane. Experimental results indicate that the applied axial strain has a good linear corresponding with the resonant wavelength shifts. The average sensitivity is 13.5 pm/με at a wide dynamic range of 0~1600 με. The temperature characteristic of the sensor is measured, which is 54.5 pm/°C in the range of 30-150°C, hence, the calculated temperature-strain crosstalk of the sensor is 4.03 με/°C. Additionally, the CO2 laser polishing method is employed to prepare the IPS-LPFG. Compared with the other methods, this method is flexible, low cost, and safe.

中文翻译：

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基于CO2激光抛光诱导斜面长周期光纤光栅的光纤应变传感器


我们提出并实验证明了一种基于倾斜平面形长周期光纤光栅（IPS-LPFG）的紧凑型应变传感器。这种不对称结构增强了应变灵敏度并缩短了传感器的长度。应变传感器的超高灵敏度归因于独特斜面的不对称厚度引入的应力微弯曲。实验结果表明，所施加的轴向应变与谐振波长位移具有良好的线性对应关系。在 0~1600 με 的宽动态范围内，平均灵敏度为 13.5 pm/με。测量传感器的温度特性，在30-150°C范围内为54.5 pm/°C，因此计算出传感器的温度-应变串扰为4.03 με/°C。此外，采用CO2激光抛光方法制备IPS-LPFG。与其他方法相比，该方法灵活、成本低、安全。