提出一种基于2×2熔锥型光纤耦合器和磁流体薄膜的光纤磁光开关.理论分析和实验结果表明,当锥形耦合区外部磁流体薄膜折射率随外加磁场变化时,耦合器的输出光功率会发生相应的改变,可以实现光的开关功能.数值计算与实验测量结果基本一致,其开关隔离度大于26 dB. A fiber optic magneto-optic switch based on a 2 × 2 taper-type fiber coupler and a magneto-fluid film is proposed.Theoretical analysis and experimental results show that when the refractive index of the external magneto-rheological film changes with the applied magnetic field, The output optical power will be changed accordingly, which can realize the light switching function.The numerical calculation is basically consistent with the experimental measurement results, the switching isolation is greater than 26 dB.