摘要
A simple and compact optical fiber directional bending vector sensor with simultaneous measurement of temperature based on the Mach-Zehnder interferometer （MZI） is proposed and experimentally demonstrated. The device consists of a piece of photonic crystal fiber （PCF） sandwiched between two single mode fibers （SMFs） with a lateral offset splicing. It shows the capacity for recognizing positive and negative directions. Within a curvature range of-7.13m-1 to 7.13 m-1, the bending sensitivities of two resonant dips with opposite fiber orientations are obtained to be 0.484 nm/m-1 and 0.246 nm/m-1, respectively. This simple MZI is formed by invoking interference between LP01 and LP21 core modes, which leads to that the sensor is not sensitive to ambient refractive index （ARI）. The temperature sensitivity has also been investigated. Two dips have obviously different sensitivities on the temperature and bending, so two parameters of both curvature and temperature can be distinguished and measured simultaneously by constructing a matrix and using one simple model interferometer.
A simple and compact optical fiber directional bending vector sensor with simultaneous measurement of temperature based on the Mach-Zehnder interferometer （MZI） is proposed and experimentally demonstrated. The device consists of a piece of photonic crystal fiber （PCF） sandwiched between two single mode fibers （SMFs） with a lateral offset splicing. It shows the capacity for recognizing positive and negative directions. Within a curvature range of-7.13m-1 to 7.13 m-1, the bending sensitivities of two resonant dips with opposite fiber orientations are obtained to be 0.484 nm/m-1 and 0.246 nm/m-1, respectively. This simple MZI is formed by invoking interference between LP01 and LP21 core modes, which leads to that the sensor is not sensitive to ambient refractive index （ARI）. The temperature sensitivity has also been investigated. Two dips have obviously different sensitivities on the temperature and bending, so two parameters of both curvature and temperature can be distinguished and measured simultaneously by constructing a matrix and using one simple model interferometer.
基金
the National Natural Science Foundation of China （NSFC） （Grant Nos. 61275125, 61308055, and 61307097）, Shenzhen Science and Technology Project （Grant No. JCYJ20140509172609175）, and Specialized Research Fund for the Doctoral Program of Higher Education （SRFDP） （Grant No. 20124408120004）.
