This year vendors are pushing expensive 3D displays, but the technology may not be as ready as they claim. We look at what's available and who needs it.
The history of 3D
3D imagery, or stereoscopy, has been around in various forms for a long time. The basic idea remains simple: use two cameras to take the same picture from slightly different angles, as a way of reproducing how the human eye sees things. Fisher-Price's View-Master toy, which many of us had as children or have given to our own children, is a good example of a basic stereoscope.
Another early system was anaglyph 3D - the system that uses the iconic red and blue glasses. That process, patented in 1891 by French scientist Louis Ducos Du Hauron (but a refinement of a technique used since the 1840s), allowed only black-and-white images at first, but newer anaglyph systems, such as the ColorCode 3D system introduced in the last decade, are able to reproduce a fairly large spectrum of colours.
Because anaglyph 3D works in just about any format (TV, movies, print) and is relatively cheap to implement, it's still widely used today for 'quick and dirty' 3D effects. Even Nvidia's 3D-enabled display hardware supports anaglyph 3D as a lowest-common-denominator way to show 3D on any display.
There are two big problems with anaglyph 3D, however. One is a general fuzziness to the image, since details tend to get lost in the red channel. The second is the way a certain amount of colour is always lost, even if you use a system that restores colour.
When 3D hit the movies in the 1950s - its first appearance was in Arch Oboler's Bwana Devil - it used polarised 3D, one of the most common systems still in use today for movies. The images for each eye were projected through a polarisation filter, and the viewer wore polarised glasses to reconstruct the 3D image. This system preserved colour information and didn't lose as much image detail as anaglyph 3D.
But it required a type of screen that preserved polarisation of light, a phenomenon where light waves are filtered so that only those vibrating in a certain direction are allowed. This limitation made the system best suited to theatrical projection rather than TV. Also, many objects on screen still sported odd halos or blurry edges, which could make it uncomfortable to watch for prolonged periods of time.
NEXT PAGE: A new technology emerges