Interest of hybrid structures for thin-film design: multilayered subwavelength microgratings

The basic principles of guided mode resonance filters constituted by a high index modulated coating deposited on a classical glass substrate are presented. A rigorous method used to compute the reflection coefficients of this kind of structures is described. We show that in some cases, computation can be made by using an approximate method. These structures, which permit one to design narrowband inverse filters, are compared to solutions based on classical multidielectric coatings.