Polarization experiment at home. Malus’s law and photoelasticity

Abstract

A polarization experiment is presented to verify Malus’s law and explain the phenomenon of photoelasticity. The experiment is carried out with an experimental setup at home, which includes to build up some holders for two polarizing acetate sheets, a white light led flashlight, a mobile phone photographic camera, and an acrylic rule. With the photographic camera, a sequence of images is recorded without the rule to verify Malus’s law and another sequence of images with the rule to see the color fringes of the photoelasticity phenomenon. The images are analyzed in their R-G-B color components and the formation of the color fringes is explained as an additive mixture of the primary colors and as an interference process.