Thrice as nice

Holographic television is one of those staples of science fiction that has proved far more difficult in practice than in theory. But a team in Germany is now showing that a combination of clever image processing and a technology most familiar from advanced jet fighters could make 3D TV possible with off-the-shelf components.

The principles behind still holograms are well known, said Hagen Stolle, chief executive of SeeReal. But transferring them to TV means producing a flat image that the eyes interpret as 3D, and which moves.

There are two problems with that, said Stolle. 'You need very high resolution. In classic holography, you can have 5,000-10,000 lines/in on your film. But for an HD TV 3D picture, you would need to calculate billions of pixels, and that's impossible. They would need to be smaller than a micron, and you would never be able to calculate all of them.'

So the SeeReal team decided to take another tack. Although when you look at a TV screen, you think you can see all of it, you cannot. The eye only looks at a small portion of the picture, but it scans the screen rapidly and the brain assembles all the information to produce the impression of the whole picture.