A variety of technologies that make images and movies appear more lifelike in print, on the computer, in the cinema or on TV. Known as "stereoscopic imaging" and "3D stereo," people sense a greater depth than they do with 2D and feel they could reach out and touch the objects. However, the effects are not just for entertainment; the more realistic a 3D training session, the greater the test of a person's reactions. For details of the rendering methods, see anaglyph 3D, polarized 3D, active 3D, lenticular 3D and parallax 3D. For a summary of content, see 3D rendering.
A Sense of Real Depth
In a 3D movie, you feel as though you could walk right into the environment.
Creating the Illusion of Depth
The creation of 3D prints, images and movies is accomplished by capturing the scene at two different angles corresponding to the distance between a person's left and right eyes (roughly 64mm). When the left image is directed to the left eye and the right image to the right eye, the brain perceives the illusion of greater depth. The stereo (left and right) frames are separated by colors, by polarization or by rapidly alternating the left and right images. A corresponding pair of 3D eyeglasses directs the images to the appropriate eye (see 3D glasses
Virtual reality is a type of 3D visualization that is used in space flight simulators as well as games and entertainment. Wearing goggles, the 3D illusion comes from being immersed in a 360-degree environment. The experience is augmented by interacting with physical wheels, buttons, dials and pedals. See virtual reality
3D still pictures date back to the 16th century when "binocular" images were viewed cross-eyed. In the 1800s, stereoscopic viewers were developed (see stereoscope
). Today, 3D stills are created with a 3D camera or a 3D lens on a regular camera.
The first feature film in 3D dates back to 1922 when "The Power of Love" debuted in Los Angeles. Using the anaglyph color method, the audience wore paper glasses with red and green lenses. Today, movie projectors polarize the left image onto the screen differently from the right image, and the audience wears lightweight, polarized glasses that filter each image to the correct eye (see polarized 3D
3D on Computers and TVs
In the late 2000s, 3D rear-projection TVs were introduced that rapidly displayed alternating left and right stereo images, requiring the viewer to wear liquid crystal shutter glasses synchronized with the TV. Eagerly welcomed by gaming enthusiasts, shutter glasses were part of NVIDIA's 3D graphics technology (see 3D Vision
), and they were eventually employed in all types of 3D TVs, including front projection, plasma, LCD/LED and OLED (see active 3D
In 2011, polarized 3D TVs emerged. Instead of "active" shutter glasses, viewers wear "passive" glasses with polarized lenses like the ones used in movie theaters (see polarized 3D
3D Without Glasses
"Autostereoscopic" 3D eliminates the eyeglasses and dates back to the 20th century when printed images first gave the illusion of depth and slight animation (see lenticular printing
). Still widely used in printing, autostereo methods evolved to display screens for cellphones and portable video games (see lenticular 3D
and parallax 3D
). 3D without glasses is the Holy Grail of the gaming and TV industry, and improvements are made every year. In 2013, the Stream TV Networks system was introduced, which promises to be a breakthrough glasses-free 3D technology (see Ultra-D