TV Makers Display Ultra Definition Technology

They call it 4k. Which has the potential to mislead, unless you are the sort of person that counts pixels on a TV screen a lot.

While many people have only just thrown away the cardboard and the polystyrene from the purchase of a new HDTV, the big tech companies are already unwrapping the next big thing.

And we are talking quite big here.

On view again at the IFA show in Berlin were 84-inch TV sets from LG, Toshiba and Sony - each boasting this new 4k or Ultra Definition technology.

Unlike HDTV, which developed monikers like 1080i or 1080p, which referred to the 1080 pixels from top to bottom of the screen, 4k is an approximate count of the horizontal number of pixels, now doubled from the 1920 on an HD set to 3840. Well, that's nearly 4000 isn't it.

Now 4k sets don't have to be 84-inch across, there are already computer monitor versions at just 20-inch across, but compacting the pixels into tighter spaces is trickier, and therefore much more expensive to do.

So far, so good. It can be done. Now, the problem is what to show on the new 4k screen.

No regular TV programmes are made in the new format; TV companies and producers are only just recovering from the burden of acquiring new kit and new skills to shoot, edit and distribute in high definition.

But the new technology is already used in many cinema multiplexes, where 4k projectors offers the best possible transfer from 70mm film stock.

Sony, one of the companies unveiling an 84-inch UDTV this week, have also made a 4k projector for the home theatre market.

But the means of getting the massive files involved from movie company to fans at home is unclear. Could better compression allow a Blu-ray disc to contain four times the information it does at the moment?

And it doesn't stop there. NHK, the Japanese broadcaster and Panasonic are already collaborating on a project using an 8k standard: four times better than UDTV and 16 times better than present day HD, which they call Super Hi Vision.

It has 22 channels of sound. They have a prototype 145" display that has to be seen to be believed: it's not 3D but it doesn't need to be - the picture is so lifelike it takes the breath away. It might as well be a window!

At the moment, only the highest specification PC can deliver files from machine to screen fast enough to feed this display - it needs a steady stream of data at over 1GB per second.