Embodiments described herein provide for optical devices with methods of forming optical device substrates having at least one area of increased refractive index or scratch resistance. One method includes disposing an etch material on a discrete area of an optical device substrate or an optical device layer, disposing a diffusion material in the discrete area, and removing excess diffusion material to form an optical material in the optical device substrate or the optical device layer having a refractive index greater than or equal to 2.0 or a hardness greater than or equal to 5.5 Mohs.