Stunning visual appearances of disordered optical metasurfaces

Nanostructured materials have recently emerged as a promising approach for material appearance design. Research has been focused so far on creating structural colours by wave interference, unfortunately leaving aside many of the important aspects that constitute the visual appearance of an object, like the respective weight of specular and diffuse reflectances, the object macroscopic shape, or the lighting and viewing conditions. Here, we unveil the high potential of disordered optical metasurfaces for harnessing visual appearance. Relying on a novel multiscale modelling platform for the predictive rendering of macroscopic objects covered by metasurfaces in realistic settings, we show how nanoscale resonances and mesoscale interferences can be used to engineer spectrally and angularly the reflected light and how these translate into unusual visual effects at the macroscale. Eventually, this leads us to discover new, stunning visual appearances that cannot be obtained with alternative structuring strategies.