Novel Microstructured Optical Fiber Sensor Based on Multi-Beam Interference

Recent progress in designing optimized microstructured optical fiber spreads an application scenario of optical fiber sensing. In this letter, we demonstrate a novel three-core microstructured optical fiber (TMOF) spliced with single mode fibers (SMFs). Due to low crosstalk and different effective refractive index between three cores in TMOF, multi-beam interference is achieved and verified based on both of experiments and theoretical analysis. In addition, the bending response could also be recorded by the transmission spectrum of TMOF because of the asymmetry of three core effective refractive index. Owing to the consistency of cores responding to temperature changes, the TMOF can effectively suppress the influence of temperature. Theses excellent sensing characteristics indicate the TMOF splicing with SMFs is promising in the field of bending, integrated Mach Zehnder devices and multi-parameter sensing measurement under different temperature.