For this project a modeling technique was devised to simulate opaque inks applied to a transparent polymer substrate. The method was based on a Neugebauer-type printing model, where the reflectance is weighted and summed to predict the color of the product. For this particular project, the materials were opaque printing inks on a transparent substrate.
The technique can be extended to be applied to a variety of materials and processes. For example, printing onto transparent plastic wrapping is a common method used in packaging. The base material can also be transparent, or both it and the substrate could be opaque. Additionally, other materials can be simulated, such as transparent inks, scattering inks, and inks applied with non-uniform thickness.
The schematic images below show the light paths of a few model extensions.
Opaque substrate and inks Opaque substrate and transparent inks Scattering substrate and transparent inks