Author Affiliations
Abstract
1 Xi’an Research Institute of High-Technology, Xi’an 710025, China
2 Department of Physics, Northwest University, Xi’an 710069, China
3 e-mail: zhongb_qin@163.com
A hybrid fiber interferometer sensing configuration for displacement and temperature measurements is proposed and experimentally demonstrated that is constructed by splicing a short section of polarization maintaining optical fiber to an end-cleaved single mode optical fiber with a tapering structure. The reflected spectrum changes with the variation of displacement and temperature. The sensing configuration uses the method of wavelength and intensity modulations for displacement and temperature measurements, respectively, to which the sensitivities are 0.01392 nm/μm, 0.0214 dBm/μm, 0.09136 nm/°C, and 0.15795 dBm/°C. Experimental results show that displacement and temperature can be measured simultaneously by demodulating the reflected spectrum.
060.0060 Fiber optics and optical communications 060.2310 Fiber optics 060.2370 Fiber optics sensors Chinese Optics Letters
2015, 13(5): 050603
提出并实验验证了一种基于马赫泽德干涉仪(MZI)的高灵敏度光纤折射率(RI)传感器。传感头由一段单模光纤(SMF)夹熔在两段较短的细芯光纤(TCF)中组成TCF-SMF-TCF结构，其总长度为9 mm。由于光纤纤芯失配导致的纤芯模和包层模发生干涉，干涉谱对传感头外部折射率的响应极其敏感。使用该传感器检测具有不同折射率的甘油水溶液，实验结果显示：传感器干涉谱的共振波长随环境折射率的增大向长波方向漂移，其折射率灵敏度在1.33 RIU～1.38 RIU范围内约为159 nm/RIU。该传感器具有结构简单、易于制造、成本较低、灵敏度高、抗电磁干扰能力强等优点，在生物化学与环境监测等领域具有较大的应用潜力。
光纤传感器 折射率 马赫泽德干涉仪 optical fiber sensor refractive index Mach-Zehnder interferometer
基于多模干涉效应的单模多模单模(SMS)结构光纤折射率传感器通常需要进行包层腐蚀来提高灵敏度，而且易受环境温度影响。为克服SMS结构的这些不足，提出了一种新型的基于纤芯失配多模干涉的光纤折射率传感器，由单模光纤色散补偿光纤单模光纤(SMF-DCF-SMF)级联光纤布拉格光栅(FBG)构成，长度不超过100 mm。对其灵敏度、线性范围和温度特性等进行了测试，实验结果显示在测量折射率为1.33~1.39的折射率液时，特征波长与折射率呈线性关系，灵敏度为232.8 nm，级联的FBG具有良好的温度校准功能。
光纤光学 光纤传感器 折射率传感器 色散补偿光纤
