基于SPR角度调制技术的溶液折射率检测系统

摘要

In order to achieve real-time monitoring of solution concentration, a refractive index sensor was developed based on surface plasmon resonance.The sensor was carried out angle-interrogated using Kretschmann configuration,making the refractive index change into the change of resonance angle.Combined with photoelectric conversion,the system collected data with computer to achieve real-time monitoring of solu-tion refractive index.In the case of other optical parameters fixed,it was found that one refractive index corre-sponded to an optimal resonance angle and resonant wavelength.The refractive index was linearly related to the optimum resonance angle,expressed as:U =-1.206d-8.140.The experimental results showed that the sensitivity reached 0.208 V/(0.001n)(n was refractive index).The system had advantages of low cost and high sensitivity.%为了实现溶液浓度的实时监测,设计了基于表面等离子体共振(SPR)原理的溶液折射率传感器及其应用系统.采用Kretschmann棱镜耦合模型,用角度调制的方法对此传感器进行定标和测量,将折射率的变化与共振角的改变对应起来,经过光电转换,用计算机采集数据,实现溶液折射率的实时检测.实验结果表明:在其他光学参数固定的情况下,一个固定的折射率对应一个最佳的共振角度和共振波长,折射率与最佳共振角度成线性关系U=-1.206d-8.140.实验数据显示,灵敏度可达0.208 V/(0.001n)(n为折射率).该系统成本低,测量精度高,有推广应用价值.