Computerized Stokes analysis of optically active polymer films

TL;DR

This paper presents a computerized method for Stokes analysis of polarized light in polymer films, aiming to enhance optical education for students in chemistry and engineering by demonstrating the technique's application and effects on birefringence.

Contribution

It introduces a practical, computer-based Stokes analysis lab tailored for non-physics majors, facilitating understanding of optical properties in polymer samples.

Findings

Polymer orientation affects birefringence and polarization.

The lab effectively demonstrates molecular polarizability effects.

Students gain hands-on experience with optical analysis techniques.

Abstract

Optics labs are an integral part of the advanced curriculum for physics majors. Students majoring in other disciplines, like chemistry, biology or engineering rarely have the opportunity to learn about the most recent optical techniques and mathematical representation used in today's science and industry optics. Stokes analysis of polarization of light is one of those methods that are increasingly necessary but are seldom taught outside advanced physics or optics classes that are limited to physics majors. On the other hand biology and chemistry majors already use matrix and polarization techniques in the labs for their specialty, which makes the transition to matrix calculations seamless. Since most of the students in those majors postpone their enrollment in physics, most of the registered in those classes are juniors and seniors, enabling them to handle those techniques. We chose to study polymer samples to aid students majoring in other disciplines, especially chemistry and engineering, with understanding of the optical nature of some of the objects of their study. The argument in this paper is that it is advantageous to introduce Stokes analysis for those students and show a lab developed and taught for several years that has successfully, in our experience, done that. Measurements of oriented and unoriented polymer samples are discussed to demonstrate to students the effects of the molecular polarizability on the sample birefringence and the anisotropic Fletcher indicatrix in general.