基于表面等离子体共振效应, 设计一种锥形光纤探针折射率传感器。通过锥形结构理论模型与SPR共振模型, 利用MATLAB与FDTD Solutions软件进行理论计算与模拟仿真, 分析锥形光纤锥度比、传感区长度和银膜厚度对传感器发生共振时的共振深度的影响。通过对比所镀膜层的结构与厚度, 从灵敏度与品质因素角度对传感器性能进行优化。结果表明随着锥形光纤锥度比增大, 共振深度出现极值；传感区长度越长, 共振深度越深；银膜在50 nm处传感器性能较优, 银/二氧化钛复合膜结构的传感器灵敏度与品质因素高于单层膜结构传感器。

Based on the surface plasmon resonance effect, a tapered fiber probe refractive index sensor was designed. Using MATLAB and FDTD Solutions software to carry out theoretical calculations and simulations, and the effect of tapered fiber taper ratio, sensing zone length and silver film thickness on the resonance depth of the sensor were analyzed when it resonates. By comparing the structure and thickness of the coated layer, the sensor performance is optimized from the perspective of sensitivity and quality factors. The results show that with the increase of the taper ratio of the tapered fiber, the resonance depth appears extremely extreme; the longer the length of the sensing region, the deeper the resonance depth; the better the performance of the silver film at 50 nm. The sensor sensitivity and quality factor of the silver/titanium dioxide composite film structure is higher than that of the single layer film structure sensor.