In Depth: 3D TV without glasses explained

Ever wish you could lose the specs and watch a 3D TV without those annoying glasses?

Analysts at Futuresource Consulting predict that by 2011 the UK will have more 3D TVs than the current front-runners, France and Germany, with one in three homes 3D Ready by 2014 - and a staggering 50 per cent by 2015.

That's an awful lot of 3D glasses - and at £100 a pop, it's a serious complaint about the 3D home experience. The solution, of course, is a 3D TV without glasses.

So-called auto stereoscopic prototypes have existed for yonks, but now Toshiba has started selling the first such TVs in Japan, albeit in tiny sizes.

Its 12-inch and 20-inch GL1 panels may be small, but they have huge prices at ¥120,000 (£914) and ¥240,000 (£1,828) respectively. Both include Toshiba's Cell Regza chipsets, though resolutions differ; the 12GL1 uses a 466 x 350 resolution panel, while the 20GL1 achieves 3840 x 2160 pixels.

That makes it a 4k2k panel, as used increasingly on monster screens, though here it serves a crucial purpose.

Lenticular lens

Effectively replacing glasses is a lenticular lens across the front, which refracts the light so a different image is seen by each eye. Unfortunately, this also lessens the visible resolution.

"The resolution is 1280 x 720 pixels when it transmits the final 3D image," a Toshiba spokesperson told TechRadar. A Full HD final image would require an 8k4k screen, better know as Super HiVision.

"Multiple viewing capability is necessary for larger format screens to enable multiple viewers to experience 3D," says James Bower, president and chief operating officer at glasses-free 3D TV developer Master Image.

"In order to technically achieve this, resolution is greatly reduced. We will begin to see more commercially viable 3D TVs without glasses when 8k4k resolution screens become standard in the market."

Meanwhile, Toshiba's 3D TVs have a very small viewing zone. "There is an ideal viewing zone, and this is best at a 40 degree viewing angle," said the Toshiba spokesperson, adding, "the suggested viewing distance is 90cm for the 20GL, and 65cm for the 12GL."

So it's case of sit close and don't move; in other words, these glasses-free 3D TVs are effectively 'personal use' 3D screens. "It's a novelty item like the Sony 11-inch OLED," says Bill Foster, senior technology consultant at Futuresource Consulting. "I don't think Toshiba has any plans to sell it outside Japan."

Multiview

The present glasses-free tech - adding a lenticular lens to the front of the screen - is all about multiview; as you walk in front of an auto stereoscopic TV your viewpoint changes, so the screen must provide as many 3D views - or 'sweet spots' - as possible, other you'll see a double image or, worse, a reverse 3D image.

"In order to format multiview content correctly, multiple perspectives are necessary," says Bower. "This is easily achieved with 3D animation, but for live action content it is much more difficult and is currently not commercially viable - eight or nine camera viewpoints are needed per stereo image."

"Nine views is the current standard, but coming down the pike is 15 views, though that will require more processing and a meaty chip," says Foster. "It has been suggested that a large screen auto stereoscopic 3D TV could need up to 100 views."

Exactly how camera rigs would be able to film from that many viewpoints is anyone's guess.

Larger screens

So will we see the big brands issuing large auto stereoscopic 3D TVs anytime soon? "It will take not less than four years for 32, 42 and 50-inch screens at consumer pricing - i.e. under £2,000," says Foster.

"We might see auto stereoscopic TVs for £4,000, but they won't be in Currys. It may need an entirely new approach to make auto stereoscopic TVs viable, rather than trying to develop on from nine-view and lenticular lens system."

Not that people aren't trying. It may be distant dream in the living room, but the wholly commercial digital signage market is pushing on with auto stereoscopic 3D TV using this lenticular lens system.

Four ex-employees of Philips 3D labs have licensed the Dutch giant's never-got-past-the-prototype (ie not good enough for the home) WOWvx technology and formed Dimenco, which showed a prototype 56-inch 4K panel with 15 views at IFA.

Aiming its €40,000+ screens at casinos, advertising agencies and cinemas, CEO Dimenco Maarten Tobias says: "We expect consumers to experience 3D digital photo frames without the need to wear glasses soon. For other consumer markets, such as 3D game consoles and 3D TV, this will take a couple of years to further optimise the technology."

Licensing the same technology from Philips is 3DFusion, which has added its own picture processing to create what its president Stephen Blumenthal calls "a new dimension in mastering, interacting, and optimizing the 3D video signal."

3D Fusion's 42-inch 3DFMax display is commercially available, but strictly for the B2B market.

Another leading light in lenticular lens TVs is Alioscopy, whose 3D screens have been installed at one of the most famous retailers in the world, SAKS Fifth Avenue in New York, and used several World cities to launch the Lexus CT-200h.

We asked Pia Maffei, Chief Operating Officer at Alioscopy USA in San Diego, when auto stereoscopic 3D screens will be available for the home. "Everyone has a different answer, buy my guess is within five years," she said.

3D gaming without glasses

Much closer is 3D gaming - and we're not talking Gran Turismo 5 in 3D on a PlayStation 3. Foster thinks that we could see a 24-inch gaming panel and a new generation of games and consoles in the not-too-distant future, but the immediate glasses-free future is for now restricted to handhelds.

First up in the UK is 2011's Nintendo 3DS, which sources tell us is using a 3.53-inch auto stereoscopic display developed by Sharp, though that's not confirmed.

Meanwhile, Master Image's slightly smaller 3.1-inch 3D screen has already found a commercial application in Hitachi's WOO H001 3D phone in Japan, which was launched in 2009 for around £500.

Master Image's Bower thinks the market for 3D handhelds is about to explode.

"We will see millions of 3D smartphones and tablets in the second half of 2011 - and tens of millions in 2012," he told us.

However thrilling 3D phones, tablets and consoles turn out to be, it's on the bigscreen where 3D without glasses will have the greatest impact.

So if not on TVs in the immediate future, could we ditch the specs in cinemas before long?

"It's not coming to your local Odeon anytime soon," says Foster, who then gives a glimpse of just how exciting it will be when it does eventually arrive.

"Watch My Bloody Valentine in 3D and the machete comes straight at you. In the next generation of 'multiview' glasses-free 3D, it will go straight down the middle of the cinema."

Tantalisingly just beyond our reach, the future of 3D isn't just about ditching the specs. It's a whole new era of holographic imagery - and it's bound to make cinema-goers go wild in the aisles.