Visualization of stokes parameters with the help of rotating–waveplate polarimeter and a liquid crystal on silicon microdisplay

Abstract

Mueller-Stokes formalism enable us to deal with polarized and unpolarized light. This formalism is hard to understand by the students because it is a new introduced concept and less intuitive than the Jones formalism. Because of that, we have designed some experiences that help students to understand and see how the Stokes parameters vary in real time. We use two commercially available optoelectronic devices. They are a Rotating Waveplate polarimeter and a Parallel Aligned Liquid Crystal on Silicon (PA-LCoS) microdisplay. The PA-LCoS acts as a variable linear retarder controlled by voltage, and the polarimeter allows us to measure the Stokes parameters in real time, and it shows the representation in the Poincaré Sphere, that it is the most intuitive representation for the Stokes parameters. Apart from the Stokes parameters, we can also use these experiences to introduce the students in a research laboratory, adding some knowledge about using LabView to automate experiments. In addition, we can use these devices and the measurements related to the light polarization to remark some basics concepts about the optical processing of information and the Fourier Transform. These experiences are suitable for different subjects, such as "Fundamentals of Engineering Optics", basic subject included in the second course of the Degree in Telecommunication, for "Photonic Devices and Optoelectronics" mandatory subject taught during the second year of the Master in Telecommunication, or the optative subject “Optical Image Acquisition and Processing” from the Master in Automation and Robotics in the University of Alicante too.