Rendering Iridescent Colors of Optical Disks

Abstract: Iridescent colors of optical disks are caused by light diffraction from their surface microstructure. This paper proposes a diffractive illumination model for optical disks based on their physical structure and the superposition principle of light waves. This model includes contributions due to diffractive and non-diffractive factors. For the diffractive part, we first model the pit periodicity for optical disks by using identical spheres and then simplify their distribution by uniform ,groups of spheres. We also propose and prove the condition for highlights on illuminated ,gr ooved surfaces; this condition provides the non-diffractive contribution. The rendered images ,using this model achieve excellent agreement,with photographs,of real optical disks. Keywords: iridescent colors, optical disks, diffraction, illumination, spectral rendering.