待测介质折射率对光纤SPR光谱的特性研究

为提高光纤传感器的灵敏度和检测精度,达到精确测量的目的。基于表面等离子体共振(SPR)理论及TFCalc软件,仿真研究光纤表面等离子体共振传感器的反射光谱特性,考查待测介质折射率在一定范围内变化对反射光谱特性的影响。研究结果表明,当入射角一定时,表面等离子体共振的最佳膜厚随待测介质折射率的减小而减小;当膜厚和入射角度不变时,表面等离子体共振波长随待测介质折射率的减小向短波长方向移动。共振吸收峰随待测介质折射率的减小移动的距离越小,且逐渐变窄,传感器的灵敏度逐渐提高。

Research on the measurement of the response of the medium the refractive index using optical fiber surface plasmon resonance spectrum

The work is to improve the sensitivity and accuracy of the optical fiber sensor and achieve accurate measurement. Based on the theory of surface plasmon resonance, the spectral reflectance characteristics of optical fiber surface plasmon resonance sensors were investigated by using TFCalc software simulation. The influence of the measurement of the refractive index of medium within a certain range change over the spectral reflectance characteristics is analyzed. The results show that, surface plasmon resonance of the best film thickness decreases with the decrease of the refractive index of medium. It is also found that the resonant wavelength shifts to the short-wave with the decrease of the refractive index of medium when the film thickness and the incident angle are constant. Resonance absorption peak increases with the reduction of the refractive index of medium. When the movement is gradually narrowed, the distance becomes short and the sensitivity of the sensor is gradually improved.