2019 Honorable Mention, Northwestern Scientific Images Contest. The vivid colors and patterns you see are a result of birefringence, which is an optical property of anisotropic materials. Ordinary objects, like this plastic dish and tube undergo stress during manufacturing as the plastic is molded into its desired form. When you observe these objects through crossed polarizers, you are able to see the stress in the object as birefringent signal zones. Birefringence can tell us important information about the mechanical properties of various materials, such as crystals and polymers.
This image originally appeared as part of Northwestern Scientific Images Contest. The contest and subsequent exhibitions are organized by Science in Society, the University's research center for science education and public engagement. Further information and opportunities to participate