共振相位调制型光纤SPR传感器理论分析与数值模拟

提出了一种基于表面等离子体渡共振(Surface plasmon resonance,SPR)相位调制的新型光纤传感模型.根据光波导理论和多层反射理论,构建了涉及多个共振激励参量的理论分析模型,并研究了共振相位调制型SPR效应激励机理和特性.模拟结果表明,入射光波长、纤芯折射率和金属膜介电常数实部绝对值增大,均会导致相位跃变所对应的液体折射率检测范围向高折射率方向发生偏移;而入射光角度和金属膜虚部逐渐增大,将会引起所对应的相位调制灵敏度逐渐退化.因此通过选择共振激励参量,可以实现对折射率检测范围和灵敏度的有效调节.

Theoretical Analysis and Numerical Simulation of Optical Fiber SPR Sensor Based on Phase Modulation

A novel optical fiber sensor model based on surface plasmon resonance phase modulation is presented. The theoretical model related to several resonance excitation parameters is established according to light waveguide theory and multi-layer reflection theory. The mechanism and characteristics of the phase modulation are studied. Simulation results indicate that with the increase of the incidence light wavelength. the refractive index of the fiber core and the absolute value of the dielectric constant real part of metal,the liquid refractive index measuring range corresponding to the phase change shifts towards the higher refractive index. With the increase of the incidence light angle and the void part of the metal,the sensitivity of phase modulation degrades gradually. Therefore, the liquid refractive index measuring range and the sensitivity can be adjusted by the selection of the resonance excitation parameter.