This year vendors are pushing expensive 3D displays, but the technology may not be as ready as they claim. We look at what's available and who needs it.
A new technology emerges
It took the invention of the liquid crystal display (LCD), among other things, to bring us active-shutter 3D technology, which is the current state of the art and the basis for most 3D displays on the market today.
Viewers don glasses with lenses that are actually LCD shutters that can alternate between blocking the left and right eye 120 times per second - in other words, they alternate at 120Hz. They then look at a screen that syncs with the glasses to show the appropriate image for each eye. The images don't have blurry fringes or 'ghosts' as they do in other systems, and either black-and-white or full-colour images can be used.
But there are downsides. For one, between the darkened glasses and the 120Hz image-switching, the image has its brightness effectively cut in half. This isn't bad if you're already in a darkened room (eg a home theatre) but can be problematic if you're not. Second, you have to actually wear the glasses, and that by itself is a distraction - doubly so for people who already have visual problems or simply find glasses annoying.
And finally, there is not yet a standard for 3D glasses. So, for example, if you give a party for your kids and want to show a 3D cartoon on your Sony TV, your kids' friends may not be able to watch the cartoon using the glasses from their Samsung TV. And at £100 a pop, it's unlikely you'll want to buy glasses for the whole crew.
The content crunch
What matters more than the tech, though, is content. Content is king, especially when it comes to 3D, and right now there's just not very much 3D video material out there, either live-broadcast or pre-recorded.
Many of the barriers in generating 3D content are both technical and economic. Much as the early years of colour created technical challenges for film and TV crews, filming in 3D requires special cameras and the technical expertise to use them. It's not insurmountable - people can be brought in and trained on new equipment in fairly short order - but only makes sense if the demand for 3D content warrants it.
Of course, there's the possibility of converting existing 2D material to 3D. For example, although the recent remake of Clash of the Titans was not shot in 3D, it did have a 3D theatrical release.
It's also possible to have consumer equipment perform re-synthesise 2D to 3D on the fly. Cyberlink's current version of its PowerDVD application comes with a feature called TrueTheatre 3D, which allows 3D video to be derived from a conventional 2D DVD. Toshiba's series of Cell TVs also promises to convert 2D to 3D on the fly but won't be released until later this year.
The problem with either approach is that it requires adding picture information that was never there to begin with, and which can't always be deduced by analysing a 2D image (or even a 2D motion stream). This was one of the problems faced by movie studios when they wanted to convert recent movies such as Titans and Alice in Wonderland from 2D to 3D. By the experts' own admission, some degree of manual work is required for the technique to really work, which means automatic conversion of 2D to 3D by software or hardware is going to yield limited results at best.
NEXT PAGE: 3D: Who needs it?