Application of Computer Vision and Lego Mindstorms in Measuring Brewster’s Angle and Refractive Index

Abstract

In this implementation, an innovative and automated measurement and educational-demonstrative resource is proposed that estimates Brewster’s angle and the index of refraction of semitransparent materials. The apparatus, built and programmed with LEGO Mindstorms model Ev3, utilizes a micro:bit board and a machine vision camera (Huskylens cam). This camera detects the intensity extinction of a reflected laser beam at the polarization angle. The Ev3 connection cables and general input/output electronic interfaces have been modified to establish communication with the intelligent brick. Upon completion, the Brewster’s angle and the index of refraction are displayed on the intelligent brick screen. It will also be shown that the percentage error corresponding to the measurement of the refractive index of a glass and acrylic sample is 1.92% and 0.47%, respectively. According to its characteristics, this resource is suitable for use in undergraduate or graduate physics and engineering laboratories/courses.

Keywords

• Brewster’s angle
• refractive index
• AI camera
• automation
• intelligent brick