BCIT Physics Department

Demonstration Manual

Optics and Light

DOP08.1 - Polarization


- To show the action of polarizer and analyzer.



For demonstrating polarized light, the two discs are placed in the support stand on an overhead projector. When the top disc is rotated, the intensity of the transmitted light drops to a minimum as the axes of polarization are aligned.

Any of the samples placed on the sample-holding sticks between the two polarized sheets will produce interference colors. In the case of things like plastic "French curves," interference is due to built-in stresses.


Wiping or scratching the polarized discs leaves very fine scratches, resulting in random polarization. Also, handle and rotate the discs by the metal edge only.

youtube logo   Watch a Polarization Demo: Filters and Sunglasses video demonstration on Youtube

- Video Created at Utah State University by Professor Boyd F. Edwards and assistants.