Equivalent Thin Film Model with Complex Refractive Index of Resonant Micromesh

Resonant micromesh with a hexagonal periodic array of micrometer-sized circular apertures is an interesting alternative to non-resonant micromesh and has the potential for superior optical transmission, while providing adequate electromagnetic interference shielding for optical windows. This paper proposes an equivalent thin film model with complex refractive index for prediction of shielding effectiveness of resonant micromesh coating. Corrected equivalent reactance and sheet resistance are given considering the thickness and duty factor of resonant micromesh. And the effects on complex refractive index of resonant micromesh parameters are analyzed. The proposed equivalent thin film model can be used to evaluate shielding effectiveness of resonant micromesh coating for optical windows.