Various embodiments of the invention include an interferometric optical modulator comprising a substrate layer and a light direction layer. Such an interferometric modulator may be integrated with a diffuser layer in a display device in a way that physically integrates the diffuser layer into the light direction layer in a way where the diff-user layer does not interact with light propagating within the light direction layer. As a result, most of the light propagating within the light direction layer does not penetrate into the diffuser which would inhibit performance of the display. In some embodiments, the interface between the diffuser layer and the light direction layer has a lower index of refraction than the light direction layer and the transparent substrate so that total internal reflection occurs at the interface.