激光微加工的光纤法布里-珀罗应变传感器

Optical Fiber Fabry-Pérot Strain Sensor Fabricated by Using Laser Micromachining

报道了一种在光纤内部通过采用157nm激光微加工一个自封闭法布里-珀罗(F-P)腔而形成的在线式全光纤标准具。实验研究了这种标准具的应变和温度特性,结果表明,在标准具两固定点相距1m的情况下,位移-相移系数和位移-谷值波长漂移系数分别为1mrad/μm和5.2pm/μm,曲线的线性度为99.92%;在18℃～500℃的温度范围内平均温度系数为0.13mrad/℃和0.64pm/℃,温度不敏感。实验证明该标准具有很好的传感特性,能满足各种应变测试的需要,如极好的条纹对比度(高达30dB)、低温度交叉敏感、大规模生产的极大潜能、低成本和耐恶劣环境能力强等。

An in-line all-fiber etalon,formed by a self-enclosed Fabry-Pérot（F-P）cavity inside an optical fiber fabricated by using 157 nm laser micromachining,is demonstrated.The strain and temperature characteristics of the etalon sensor are investigated.The results show that the strain sensitivity is 1 mrad/μm and 5.2 pm/μm,and the linearity is 99.92% with two fixed point at a distance of 1 m.Furthermore,the temperature sensitivity is 0.13 mrad/℃ and 0.64 pm/℃ at the range of 18 ℃ to 500 ℃.Experimental results show that the etalon can meet versatile applications for stain measurement because of its perfect sensor characteristics,such as excellent interferometric fringe contrast of up to 30 dB,low thermal cross-sensitivity,great potential to realize mass-production,low cost,and super capability to operate in harsh environments.