Abstract In this paper, a novel strain sensor based on Depth-Modulated Long Period Fiber Grating (DM-LPFG) is presented and demonstrated. One side polished deformations with different milling depth are fabricated by a high frequency CO2 laser, so the DM-LPFG possesses a staircase-shaped structure. This kind of structure provides the high strain sensitivity of DM-LPFG. Experimental results clearly demonstrate that the structure has excellent mechanical capacity and repeatability. The sensor has a considerable strain sensitivity, which can reach up to 27.4 pm/μe with the range of 0–450 μe, it is an order of magnitude higher than conventional CO2 laser induced LPFG. The temperature characteristic is 49 pm/°C with the range of 30–170 °C. Furthermore, the strain sensor possesses a compact structure, with a total length of 9 mm.

中文翻译：

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基于深度调制长周期光纤光栅的新型应变传感器

摘要 在本文中，提出并演示了一种基于深度调制长周期光纤光栅 (DM-LPFG) 的新型应变传感器。采用高频CO2激光制造不同铣削深度的一侧抛光变形，因此DM-LPFG具有阶梯状结构。这种结构提供了 DM-LPFG 的高应变敏感性。实验结果清楚地表明该结构具有优异的机械性能和可重复性。该传感器具有相当大的应变灵敏度，在 0-450 μe 范围内可达到 27.4 pm/μe，比传统的 CO2 激光诱导 LPFG 高一个数量级。温度特性为 49 pm/°C，范围为 30–170 °C。此外，应变传感器结构紧凑，总长度为9 mm。