## Birefringence
![[Drawing 2024-09-24 23.36.47.excalidraw.svg]]
Image from https://commons.wikimedia.org/wiki/File:Positively_birefringent_material.svg, By Mikael Häggström - Own work, Public Domain, https://commons.wikimedia.org/w/index.php?curid=10953566
### Understanding birefringence