Reconstruction of optical images of graphene-based materials coated on dielectric substrates

The colors of thin and thick layers of graphene and graphene oxide films on either SiO₂ or Si₃N₄ grown silicon substrates were generated by a theoretical calculation procedure. The effects of the thicknesses of the material and the dielectric layers on the visibility of the graphenebased materials were investigated. The theoretical investigation was supplemented by measurements of the thicknesses of the material layers using either an atomic force microscope or a profilometer, depending on the thickness range. By combining the color calculation procedure with the measured thickness profiles, optical images of graphene-based materials on dielectric substrates can be reconstructed. The reconstructed image corresponds well to the real microscope image, which suggests that the image reconstruction procedure is a convenient way to investigate colors and determine the thickness of graphene-based materials.