3D Films "How do they work?"

Although most of us have experienced a 3D film at least once in their lives, many do not understand the science of how the cinema industry manages to project a 3D image from a 2D screen.

When viewing an object in real life, the left eye sees a bit more of the left side of the object while the right eye sees a bit more of the right side. Your brain then combines the two images, allowing you to see the full 3 dimensional effect.

To simulate this theatres use polarized light, or light waves that vibrate on only one plane. Although most forms of light that we see is unpolarized, they can be converted into polarized form using a polarizing filter. These filters have tiny lines etched into them that allow only light vibrating on the same plane as the lines through.

Duringthe filming process, the film is recorded useing two cameras set side by side to simulate the left and right eyes. Then, the cinema will project the two slightly different images onto the big screen, but they will use to different polarizing filters on the cameras. The two seperate, now polarized, images will then reflect off of the screen back onto the audience who will be wearing polarizing glasses. These glasses will only allow the left image to pass through to the left eye and the right image to pass to the right eye, fooling the audiences brains into "seeing" an image as if they were actually there.