Colors from polarizers and birefringent films

In this paper we analyze the interesting artwork of Austine W. Comarow that creates colored images from colorless birefringent films. This artwork consists of birefringent polymer films sandwiched between two polarizers, similar to a polariscope. We explain quantitatively the main features observed in Comarow's work. We derive the equations that predict the colors generated in the system as a function of the thickness and the angles between the films. We illustrate the phenomena with simple homemade devices.