Photos: The technology behind 3D movies

The Dolby 3D system uses a wheel that spins at 4,800rpm--fast enough to switch between left-eye and right-eye views six times for each frame of the movie. It's divided into two halves, each with a filter coating that lets through only particular frequencies of light, one set for the left-eye view and one for the right-eye view.

Photo by Dolby Laboratories