基于色相算法的表面等离子体共振成像传感器

摘要

本文报道了一种基于色相算法的彩色表面等离子体共振(SPR)成像传感器,该传感器不仅能够对发生于SPR芯片表面的物理化学反应进行直观的图像观测,还能基于色相算法对这些表面反应进行定量分析.利用自制的波长/图像同步检测型SPR传感器,实验获得了不同共振波长对应的共振图像,然后借助色相算法求得每一幅共振图像对应的二维色相分布及其平均色相,建立了共振波长与图像平均色相的依赖关系,用于优化基于色相参数的SPR折射率灵敏度.实验选择起始共振波长为650 nm,测得基于色相的折射率灵敏度为3 338/RIU,是基于共振波长的折射率灵敏度的1.49倍.利用彩色SPR成像技术能够直观地观测到金膜表面涂布的聚四氟乙烯薄膜的不均匀性,再通过计算图像局部区间的平均色相,可以定量获得不同薄膜厚度对应的折射率灵敏度.实验结果证明了基于色相算法的彩色SPR成像传感器明显优于常规SPR传感器.%A Surface Plasmon Resonance Imaging sensor based on hue algorithm has been presented.The sensor can be used for observing the chemical or physical reactions on the surface of the SPR chip.What is more, the hue algorithm can be used to analyze these reactions on the surface of the SPR chip quantitatively.First of all, the wavelength/image synchronous detection SPR sensor was used to obtain the resonance spectra with different resonance wavelengths and the corresponding color images.And then, the hue algorithm was used to get the hue distribution of the image and determine the relationship between the resonance wavelengths and the average hue.Considering the relationship between the average hue and the resonance wavelengths, the initial resonance wavelength was set as 650 nm.Under this circumstance, the sensitivity of the hue is about 3 338/RIU, which is 1.49 times as the sensitivity of the resonance wavelength.The Teflon layer was fabricated on the gold film, and the thickness of the layer was analyzed by the color SPRI image.The hue of the local areas was calculated to determine the sensitivity of the different thicknesses of the Teflon layer quantitatively.The experimental results indicate that the SPRI sensor based on hue algorithm is better than the conventional SPR sensor distinctly.