High-Sensitivity Sensor Based on Surface Plasmon ResonanceEnhanced Lateral Optical Beam Displacements

Abstract

We present a new optical sensor based on surface plasmon resonance (SPR)enhanced lateral optical beam displacements. Compared with thetraditional SPR methods, the new method provides higher sensitivity tothe sensor system. Theoretical simulations show that the refractiveindex (RI) detection sensitivity of the SPR sensor based on thedisplacement measurement has a strong dependence on the thickness of themetal film. When the optimal thickness of the metal film is selected,the RI resolution of the SPR sensor is predicted to be2.2×10−7 refractive index units (RIU). Furthermore, it isfound that the incidence angle can be used as a parameter to adjust theoperating range of the sensor to different refractive index ranges.