The First 3D Movies

3-D movies have gone through several waves of popularity. They have appeared several times in the 20th and 21st centuries, with new developments in technology enabling better effects with each new incarnation. Rotating discs, polarizing glasses, anaglyphic glasses, coupled polarizers and optical retarders, and the use of electro-optic shutters each provided small advantages over previous technology. But the basic idea is simple, and was used in the 19th century stereoscope—present each eye with an independent view from a different perspective so that the parallax enables the brain to fuse them into one stereoscopic image. Who invented the first 3D movies? The idea is much older than most people suspect, dating back to the very beginning of cinema.