表面等离子体共振传感是基于光学消逝波与金属表面等离子体波共振的一种高灵敏度、快速、无标记的测量方式。光纤的表面等离子体共振传感具有在线测量、体积小、抗电磁干扰等优点。为提高折射率传感灵敏度,采用轮式侧边抛磨法抛磨掉多模光纤的全部包层和部分纤芯,并采用溅射法在光纤抛磨区先镀高折射率的铬层然后镀金膜,制作了侧边抛磨光纤表面等离子体共振传感器。研究结果表明:该传感器可实现液体折射率在1.333~1.431 RIU范围的测试,平均光谱灵敏度为4.11×103 nm · RIU -1,在1.417~1.431 RIU折射率范围内光谱灵敏度达1.09×104 nm · RIU -1,折射率测量范围和光谱灵敏度均优于已报道的结果。此外,该传感器具有良好的稳定性与重复性实验测试,最小分辨率约为3.6×10-5 RIU。该传感器光谱灵敏度高、检测范围大、尺寸小及良好的稳定性与重复性等优点,可被用于食品检测、环境监测、生物医学检测等相关领域。
Surface plasmon resonance ,which utilizes the resonance of optical evanescent wave with the metal surface plasmon wave ,has been developed into a high sensitivity ,rapid ,label-less measurement method for chemical and biological analysis .In order to improve the spectral sensitivity in refractive index for a side polished fiber surface plasmon resonance sensor ,the whole cladding layer and part of core of a multimode fiber was polished off .Additionally ,an extra chrome layer with relatively high re-fractive index was coated on the polished zone before a gold film .The results showed that the sensor can measure the refractive index range from 1.333 to 1.431 RIU ,with the average spectral sensitivity of 4.11× 103 nm · RIU -1 ,which is better than the reported results .Especially ,in the refractive index range of 1.417-1.431 RIU ,the sensitivity reaches to 1.09 × 104 nm - RIU -1 .The minimum resolution of approximately 3.6 × 10-5 RIU was estimated by a combination analysis with the sensor sen-sitivity and stability .The superiorities possessed by the proposed sensor in high sensitivity ,wide detection range ,small size and good stability and reproducibility ,etc .,make it a good candidate for food testing ,environmental monitoring ,biomedical testing and other related fields .