Published In
European Journal of Physics
Document Type
Article
Publication Date
6-6-2025
Subjects
Physics -- pedagogy, Optics -- Experiments
Abstract
Interesting and pedagogically useful physics can be found in the halo produced by a laser pointer directed into a shallow body of water. We describe a simple model for this phenomenon using geometric optics and support this model with empirical evidence. We also discuss and verify extensions to this model that explain variations in the visual pattern. These variants include a double halo pattern and a disk of dim light that can be produced with minor modifications of the single halo configuration. Although the level of complexity differs, all of these models rely on the same ray optics, specifically refraction and diffuse, specular, and total internal refection. We discuss several scenarios for integrating halo effects into undergraduate physics instruction. This phenomenon offers instructors a realistic application of many introductory optics concepts packed into single effect that is practical and appropriate for multiple teaching environments.
Rights
Original content from this work may be used under the terms of the Creative Commons Attribution 4.0 license. Any further distribution of this work must maintain attribution to the author(s) and the title of the work, journal citation and DOI.
DOI
10.1088/1361-6404/add5aa
Persistent Identifier
https://archives.pdx.edu/ds/psu/43690
Citation Details
DeStefano, P. R., & Widenhorn, R. (2025). Teaching Diffuse, Specular, and Total Internal Reflection via a Halo Effect. European Journal of Physics.