Аналитическое описание спектральных характеристик сенсора коэффициента преломления на основе отражательного интерферометра

The analytical formulas, describing spectral properties of sensor based on oblique incidence reflection interferometer in Kretschmann optical scheme. The sensor is designed for measuring the refractive index of analyte (liquid or gas) exploiting the effect of total internal reflection in multilayered metal-dielectric structure. The properties of comprised in the structure thin metal layer, that are necessary for optimization of sensor’s spectral profile, are defined. The spectral profile represents peaks with varying width. The oblique quaterwave dielectric layers are also used in the structure. The analytical properties of sensor depending on light polarization are given: resolution, sensitivity, contrast and figure of merit (FOM). It is shown in the paper, that sensor shows high grade parameters in both polarizations, but it is preferably to use S polarization to maximize FOM due to higher finesse in the sensor structure. The method of fabrication of such sensor structure with optical control during vacuum sputtering is proposed.