It was found from experiments with thin films that there are two modes in the absorption spectrum of SiO 2 : one is strongly expressed in reflection, i.e., it appears as a peak in R(λ ) when n is large, and the other is manifested as a strong peak in T (λ ). The mode corresponding to the peak in T is defined by the absorption, i.e., it has a good correspondence with the values of k and ε 2 (imaginary parts), which are the attenuation coefficients. The mode obtained in R is similar to the absorption mode, but it is not significantly coupled to the plasmon resonance of the metasurface. In other words, it did not show the anti-crossing phenomenon typical for the the strong coupling. The enhancement of the reflection peak intensity simultaneous with narrowing of the spectrum of the meta-surface were observed (Fig. ). This suggests that the plasmon resonance causes an optical interference with the scattered field. These results imply that it is essential to consider the absorption-derived peaks to understand the coupling phenomena in MIM metasurfaces.