一种新型的高灵敏度光纤传感器的研究

Research on a New Optical Fiber Sensor with High Sensitivity

为了提高传感器的灵敏度和线性度,该文提出了改变光纤的表面粗糙度和探针类型。首先通过自主搭建轮式光纤侧面抛磨系统,将光纤的一端镀一层Ag膜作为反射镜面,制备得到表面较粗糙的D型光纤探针。通过检测探针的传感特性发现,被测溶液折射率的变化会引起不同能量的吸收,由此使光功率计接收的光功率发生改变。经测试,制备的D型光纤传感器稳定性及线性度均很好,尤其是抛磨损耗为18 dB的传感器的灵敏度和线性相关系数分别高达66.02 dB/RIU和99.58%。通过对折射率的精度进行测量和计算,得到其精度高达0.00004。结果表明,该传感结构具有广泛应用于生化传感(如新冠疫情等)及对环境污染程度进行实时监测的潜力。

In order to improve the sensitivity and linearity of the sensor,it is proposed to change the surface roughness of the optical fiber and the type of probe.Firstly,the D-type optical fiber with rough surface is prepared by the self-built wheel optical fiber side polishing system,and then one end of the optical fiber is coated with a layer of Ag film,which can be used as a mirror,so as to obtain the D-type optical fiber probe.Finally,when detecting the sensing characteristics of the probe,it is found that the change of the refractive index of the measured solution will cause the absorption of different energy,which will change the optical power received by the optical power meter.A series of experiments results show that the prepared D-type optical fiber sensor not only has very strong stability,but also has very good linearity.In particular,the sensitivity and linear correlation coefficient of the sensor with polishing loss of 18 dB are as high as 66.02 dB/RIU and 99.58%,respectively.The measurement and calculation of the accuracy of refractive index show that the accuracy can be as high as 0.00004.The results show that the sensing structure has the potential to be widely used in biochemical sensing(such as COVID-19 pandemic)and real-time monitoring of environmental pollution.