基于环行腔光纤激光器的应力传感器

Strain sensor based on ring cavity fiber laser

提出并演示了一种基于大直径光纤锥的马赫曾德尔干涉仪应力传感器。以锥形光纤马赫曾德尔干涉仪作为滤波器,对掺铒光纤的增益谱进行梳状滤波,最终在环行光纤谐振腔中实现激光的产生并输出。所采用的马赫曾德尔干涉仪在作为滤波器件的同时也能够对光纤轴向应力进行传感,最终实现激光器输出波长随应力增加而向短波长方向漂移,实验结果显示其在波长1 557 nm附近传感的敏感度达到了3 pm/με。基于该锥形光纤的马赫曾德尔干涉仪具有成本低、制作简便和机械强度高的优点,使其更有利于商业化规模制作。

An up-tapered fiber strain sensor based on Mach-Zehnder interferometer （MZI） was proposed and demonstrated. With the MZI as a filter, the laser was finally generated in the optical fiber ring resonator through comb filtering at the gain spectrum of erbium-doped fiber. The MZI could work as filter as well as carry on the sensor of optical fiber axial strain, and thus realize the output wavelength of the laser blue-shifts with the increase of strain. The experiment result shows that the sensor around the wavelength of 1 557 nm exhibits the axial strain sensitivity of 3 pm/με by monitoring the wavelength shift. Moreover, the up-tapered MZI fabrication process is very simple, cost effective and high mechanical strength.