All-Dielectric Metasurfaces for Reflection and Transmission-Mode Color Filter Arrays

We report all-dielectric metasurface color filters working in reflection and transmission mode. The reflection mode filters are made by a-Si cylindrical nanopillars on top of a silica substrate, whereas the transmission mode filter structures are complementary in nature, i.e. holes on the poly-Si layer. The experimental results show that in reflection mode, it is possible to design pixels of 0.5μm profile. Also the numerical study shows that going beyond conventional uniform shapes, it is possible to enhance the performance parameters of the spectral filters.