3D movies provide an opportunity for a more realistic experience at the theater. How do they work? The movies are shot with 2 cameras, each recording a separate image, one for the right eye and the other for the left. Two separate projectors are then used. For the 3D effect to work, each eye must only see the image from one projector, and not the other. The older technique for doing this was to use red and green filters, which distorted the colors in the movie. Newer technology uses polarization. The same principle used in polarized sunglasses, polarization in 3D movies allows each eye to see only the image for which it was intended, by orienting the polarizing filters in different directions.
Polarized glasses are used during children’s eye exams in order to test their ability to process depth in a normal fashion.