Is 3D television finally ready for prime time?

http://www.economist.com/science/displaystory.cfm?story_id=12958009

Jan 16th 2009
From Economist.com

TELEVISION was called a medium, the sadly missed Ernie Kovacs once wryly remarked, because it was neither rare nor particularly well done. That’s still largely true, though it’s at least changing for the better, as the medium is finally wrestled from the grasp of network broadcasters and cable companies.

Attendees at last week’s Consumer Electronics Show (CES) in Las Vegas saw many technology trends converging on the television set. Apart from being used to play video games and DVDs, the latest televisions are coming complete with browsers and broadband connections—ready to download video directly from online sources such as Hulu and YouTube. So you no longer have to watch internet video on a crummy computer screen when the 52-inch HDTV in the living room can do a far better job.

And that’s just the beginning. Television manufacturers are learning other tricks perfected by movie and computer makers. The aim is to give consumers an even richer viewing experience than they had from high-definition television.

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The loudest buzz at CES this year came from manufacturers bent on bringing full 3D effects into the living room. Where several years ago the latest television sets were hailed as “HDTV ready”, a handful of TV makers are now touting models that are “3D ready”.

Mitsubishi’s latest 3D-ready HDTV set, a 65-inch model called LaserVue, goes on sale this summer, with a 73-inch version following later in the year. Meanwhile, Panasonic exhibited a 103-inch plasma display showing 3D video from a Blu-ray player.

Panasonic expects 3D television to follow much the same trajectory as HDTV did earlier this decade: a slow start, then a rapid ascent in sales once enough content exists to attract mainstream buyers.

With that in mind, Panasonic is establishing a post-production authoring centre to help Hollywood studios turn their growing slate of 3D films into 3D Blu-ray discs. The company has high hopes that “Avatar”—the first of a string of 3D blockbusters expected from Disney, Universal, DreamWorks and Sony this year—will kick-start the home-3D trend.

Best known for its audio technology, Dolby Laboratories is also negotiating with film studios and video-game developers in a bid to bring 3D into the home. Dolby is already a major equipment supplier to cinemas; its 3D gear is used on 400 screens around the world. The firm’s home version works with any 3D-ready television set hooked up to a Blu-ray player.

For its part, Mitsubishi announced a deal with Nvidia, a maker of PC graphics-cards, and Aspen Media Products, which builds media servers, to develop 3D-television content. The first releases, expected later this year, will be popular video games such as Tiger Woods PGA Tour.

Separately, Nvidia showed a $199 kit, complete with spectacles, that allows normal 2D-video to be displayed on a computer screen in 3D. A gizmo that does the same for high-definition television is expected to follow shortly.

Also at the show was the world’s first portable 3D projector for the home, developed by projectiondesign of Norway. Meanwhile, Philips unveiled several new 3D television sets, including a 52-inch LCD model for which special glasses are not needed.

But don’t get too excited about the lack of funny specs. The “autostereoscopic” displays that don’t call for special glasses tend to have a fairly small “sweet spot”, and therefore a limited viewing angle. There are technical solutions, but they don’t come cheap. That’s why most 3D films continue to rely on glasses of one sort or another.

At least, the cardboard goggles with blue and red filters worn by moviegoers in the 1950s have now gone for good. In their place are clear plastic glasses developed for the movie industry with left and right lenses that are either polarised differently, or contain electronic shutters that blink rapidly on and off in sync with the left and right images being flashed alternately on the screen. Both are much easier on the eyes than the old “anaglyphic” coloured lenses.

To view a film or video game in 3D, left and right images of each video frame are filtered and sampled separately in a checkerboard grid pattern—with the grid for the left eye offset slightly to left, and the grid for the right eye slightly to the right. The separate digital images are sent to the screen, where they are projected as a combined stereoscopic image that is perceived differently by each eye. The result is an impression of depth.

But as often the case with 3D television, depth comes at the price of image quality. That’s because to do the job properly stereoscopic 3D displays require twice as much imaging bandwidth as ordinary 2D displays.

The cheap and cheerful solution is to halve either the image’s horizontal or vertical resolution—so the left and right images can be crammed into the same bandwidth as a 2D image. Unfortunately, that sacrifices the picture’s vertical or horizontal resolution.

One nifty solution comes from Texas Instruments. The company’s unique DLP (digital light processor) technology uses a matrix of microscopic mirrors that can be individually rotated to reflect light or not, and thereby switch the screen’s individual pixels on or off. The speed of the flipping mirrors allows full-resolution images for left and right eyes to be displayed in the same one-sixtieth of a second as other systems using half the visual information.

The drawback is that viewers must use the more expensive shutter-type glasses. The benefit is a full 1080p HDTV picture in all its pin-sharp 3D glory. Mitsubishi and Samsung use Texas Instruments’ 3D engine in their latest television sets.

But the Texas Instruments approach is not the only way to display high-definition 3D television. Chastened by the prolonged format war that badly (some say fatally) wounded the DVD’s successor, electronics makers are anxious to avoid another Blu-ray-versus-HD-DVD fiasco.

Last August, no fewer than 80 companies signed up for a Society of Motion Picture and Television Engineers gathering to set standards for 3D television. The meeting established a task force, which will report in March. It will then take at least another 18 months to hammer out a draft standard, and perhaps even longer: the Blu-ray Disc Association and the Consumer Electronics Association will each want a say.

The last time your correspondent reported on 3D television was in 1996. He naively thought it would be in living rooms by the turn of the millennium. Ever the optimist, he’s ready to bet that, this time, 3D in the home is for real. That’s because, unlike last time, Hollywood is now desperate for something—anything—that can revive its dwindling fortunes, caused by the collapse of home DVD sales. Eye-popping 3D movies, repackaged for home consumption, could be the answer to the studios’ prayer.