| The dispersion characteristics of the metallic thin film is one of the essential factors for generating surface plasmon resonance. Surface plasmon resonance(SPR)is a physical optics phenomenon, The sensing technology based on the principle of SPR was widely applied to the field of optics, chemistry, biology, environment, food analysis, medical treatment and pharmacy, however, the performance of these sensors was closely related to the dispersion characteristics of the metallic thin film.In this paper, the dispersion characteristics of the metallic thin film was measured by the method of SPR based on the analysis of the principle of SPR and the dispersion of metallic thin film.On the theoretical side, the theory of SPR and the research of the dispersion of metallic thin film based on the theory of SPR was introduced in this paper, the resonance condition was deduced from the Maxwell equations and the boundary conditions, and the revise of the resonance condition was analyzed and calculated theoretically. The theory of the dispersion of metallic thin film was analyzed by the Drude model.On the experimental side, a angle scanning SPR measuring system which utilizes a Kretchmann configuration was constructed by using a elliptical reflector and a high-precision rotating platform which was electrically controlled, a zero position locating device based on a photoelectric switch was mounted and a photoelectric converting circuit was made, the system can run automatically by using the LabVIEW programs of driving and data acquisition.Basing on the principle of angular interrogation of SPR and the analysis of influence factors to the theoretical curves of the angular modulation of SPR, such as the center wavelength of light source, the thickness and dielectric constant of metallic thin film, the thickness and dielectric constant of gold thin film was calculated simultaneously by using the LabVIEW programs and the data measured. |
PDF Full Text Request