How 3-D television works

The new generation of 3-D television sets work by dividing picture images into two sets — one for each eye. The viewer must wear special glasses, so each eye captures a different image, creating the illusion of depth. Production of the video involves two connected cameras — one for the left-eye image and the other for the right.

Manufacturers have developed two incompatible technologies for consumer 3-D glasses. With polarized glasses — which cost less than a dollar — each lens blocks a set of images transmitted in certain types of light. Active 3-D glasses, on the other hand, cost about $100 and are better suited for LCD screens. They have battery-powered shutters that open and close rapidly, so each eye sees different views of each frame. Manufacturers have not yet said whether they will include the glasses with the TV sets.

Future technology will allow viewers to watch 3-D without glasses. But the technology has severe limitations, such as forcing viewers to sit a certain distance from the video display. That technology is not expected to be viable for the next 15 years.

Also, production gear for 3-D programming is in the early stages of development, and incompatible 3-D transmission standards remain. Panasonic demonstrated its new $21,000 3-D camcorder at CES. Toshiba will sell the high-end “Cell TV” in the United States this year, and it will be capable of converting standard 2-D video to 3-D HD. The Cell TV set-top will have 1TB of hard-disk storage and will include a built-in Blu-ray player.

Sony will go into its vast library to convert 2-D programs to 3-D. One area of special interest is music performances. Among the demos was a 3-D version of Jimi Hendrix’s performance at Woodstock.