基于多模结构的光子晶体光纤应变传感器

Photonic crystal fiber strain sensor based on multimode structure

基于工程结构的应变传感器在结构受力和健康状况领域应用广泛,其中采用(mach-zehnder interferometer.MZI)的光纤传感器因其具有体积小、抗电磁干扰性强、灵敏度高等独特优势而在应用领域受到众多青睐。为了提高光纤折射率传感器的灵敏度和可操作性,设计了一种基于Mach-Zehnder干涉的新型应变传感器,并进行了实验验证。该传感器采用单模光纤(single-mode fiber,SMF)-分束器-光子晶体光纤(photonic crystal fiber,PCF)-合束器-SMF结构,其中分束器和合束器均使用多模光纤(multimode fiber,MMF)进行实验。从传感结构方面着手,以寻找操作简单、成本低、可重复性高并且具有高灵敏度的应变传感器。实验结果表明,当采用具有对称结构的MMF时,在0~800μm,该应变传感器应变的灵敏度最大为-2.87 pm·με^(-1)。该装置具有灵敏度高、体积小、可重复性高等优点,在应变测量领域具有实际应用价值。

Strain sensor based on engineering structures is widely used in the field of structural forces and health conditions,where MZI-based photonic crystal fiber(PCF)sensors are more favored in this field due to their unique advantages of small size,immunity to electromagnetic interference,and high sensitivity.To improve the sensitivity and operability of optical fiber refractive index sensors,a new strain sensor based on Mach-Zehnder interference is designed and implemented and verified by experiments.The sensors are composed of single-mode fiber(SMF)-beam splitter-photonic crystal fiber(photonic crystal fiber)-beam synthesizer-SMF.Multimode fiber(MMF)is used for the experiment of beam splitter and beam combiner.The sensing structure is approached to find a strain sensor with simple operation,low cost,high repeatability,and high sensitivity.The experimental results show that the strain sensor has a maximum sensitivity of-2.87 pm·με^(-1) in the strain range of 0~800μm when the MMF symmetric structure is used.This device has the advantages of high sensitivity,small size,and high repeatability,and has practical applications in the field of strain measurement.