Polarized light is used in science and engineering for analyzing materials and detecting issues, like detecting stress points in plastic.
- What do you notice about the various items here when you look at them through the filter?
- What happens when you turn the filter 90 degrees?
- Can you change the stress on an item? How can you tell?
Glasses for 3D movies use polarizing filters to give the 3D effect! Movies are filmed through polarizing filters, and then you watch through glasses with the same filters! Each lens on a pair of 3D glasses has a different polarizing filter. So one lens lets in one wave of light and the other lens lets in a different wave of light; each eye sees a slightly different picture. Looking through the two lenses at the same time, your brain combines the two images and the result is 3D!