基于可饱和吸收稳频技术的光纤激光应变传感特性研究  

Strain Sensing Characteristics of Fiber Laser Based on Saturable Absorption Frequency Stabilization Technology

作　　者：杨润涛[1,2] 祝连庆[1,2] 张钰民 刘锋[1,2] 娄小平[1,2] 

机构地区：[1]北京信息科技大学光电信息与仪器北京市工程研究中心,北京100192 [2]北京信息科技大学光电测试技术北京市重点实验室,北京100192

出　　处：《纳米技术与精密工程》2016年第3期201-205,共5页Nanotechnology and Precision Engineering

基　　金：教育部"长江学者和创新团队"发展计划资助项目(IRT1212);北京市科技计划资助项目(Z151100003615010);北京市教育委员会科技发展计划资助项目(KM201411232022)

摘　　要：提出了一种环形光纤激光用于光纤传感的方法,结合光纤可饱和吸收体稳频技术,获得稳定的激光输出,并成功将其应用于应变传感.使用980 nm激光二极管作为泵浦源,长度为2 m的掺铒光纤作为增益介质,通过光环形器引入未泵浦的掺铒光纤作为可饱和吸收体形成窄带滤波器,并选用高反射率光纤光栅作为波长选择元件.可饱和吸收体长度为4 m时获得了稳定的激光输出,输出3 dB带宽小于0.2 nm,边模抑制比大于70 dB,阈值电流为63.3 mA.通过选频光纤光栅对等强度梁应变的感知引起的光纤激光输出调谐,实现0~2100με应变传感检测,对这种掺铒光纤激光的应变特性进行了实验研究,得到了应变与激光峰值波长的线性关系.实验结果表明：该激光传感器获得了很好的线性度和重复度,线性拟合度高于0.999.A ring cavity Er-doped fiber laser sensor based on fiber Bragg grating （ FBG） was proposed, and stable laser output was acquired together with fiber saturable absorption frequency stabilization tech-nology, which has been successfully applied to the strain sensor. The laser sensor uses 980 nm LD as pump source and 2 m Er-doped fiber as gain medium. An un-pumped Er-doped fiber was employed as saturable absorber to form an optical narrow-bandwidth filter, and a FBG with high reflectivity as coarse wavelength selective component. In the experiment, a stable laser output was achieved when the optimum length of saturable absorber was 4 m, the 3 dB bandwidth of output spectrum was less than 0. 2 nm, the side-mode suppression ratio greater than 70 dB, and the threshold current of the fiber laser 63. 3 mA. The output of ring fiber laser was tunable with the wavelength change of frequency selective grating, sens-ing the strain of the uniform strength beam. The strain sensing characteristics of the laser were studied. Within the range of 0—2100 με, the output peak wavelength of Er-doped fiber laser sensor was meas-ured. Experimental results show that the laser sensor enjoys a good linearity and repeatability and that linear fitting of the laser sensor is higher than 0. 999 .

关 键 词：光纤光栅 环形腔 掺铒光纤 可饱和吸收体 灵敏度 

分 类 号：TN248[电子电信—物理电子学]