After years of speculation, the 3D display might soon be upon us. Digit checked out the technological advances that could make it happen.

Sharp's Yasushi Yamamoto thinks the time may be right for three-dimensional (3D) display technology. Twenty years after a generation of movie-goers filed into theaters, 3D glasses in hand, to watch a mechanical shark lunge at them in Jaws 3D, Yamamoto says a new generation of display technologies may soon emerge.

He's not alone. Led by Sharp and Sanyo, more than 100 companies formed the 3D Consortium (3DC) a year ago to jointly promote 3D hardware and software. Among the group, of which Yamamoto works for the management secretariat, are some of the best-known names in electronics, such as Sony, Toshiba, Samsung, and LG.

The group formed to solve a classic chicken-&-egg problem with 3D, says Yamamoto. Without an installed base of hardware, there is no software, but nobody wants to pay a premium for hardware without software.

The kick the industry needs might come from Sharp. It has developed a dual-mode LCD that can display 3D images, or be switched to act like a conventional 2D display. That's a big step, because most previous displays were 3D only, and required lots of specially written software. Few people want to invest in such a screen without the promise of content.

The 3D function of the display works thanks to a set of vertical black lines in front of the display. These lines, known as a parallax barrier, are positioned such that each of your eyes only sees half the pixels. This effectively halves the total resolution of the display but allows a 3D image to be seen without any special glasses and, Yamamoto says, the 3D effect more than makes up for the lower resolution.

Sharp has already put this display into two cellular telephones for NTT DoCoMo and combined sales of the handsets have passed the million mark, says Yamamoto. That's pretty impressive for a 3D device although he admits it's impossible to know how many people bought the phones because of the 3D screen and how many people are using the 3D content. The telephones came with two Java games that make use of the 3D mode.

Causing much more excitement in the 3D community recently has been the release by of a couple of notebook computers using the switchable screens from Sharp - Sharp's PC-RD3D, launched late last year, and NEC's Lavie S LS900/8E, launched in January in Japan. In 2D mode you couldn't tell the display apart from other Windows XP-based notebook computers but on switching to 3D mode, objects begin jumping out of the screen.

For this type of display to really take off among consumers, researchers and product designers are going to have to make this technology stable on large screens that can be used in living rooms, said Ashley Domis, an analyst with ARS in California.

"They're cool for gaming, they're cool for movies, but who wants to sit around a 17-inch monitor and watch a three-hour movie?" Domis said.

Sanyo might have a solution soon. More than a year ago it demonstrated a prototype 50-inch PDP (Plasma Display Panel) that can show 3D images and said it hopes to be in a position to begin supplying samples of the display in the first half of 2004.

What they are likely to cost is unknown. The two notebooks from Sharp and NEC both have hefty price tags of $3,000 and $3,600 respectively. That's probably too much to enable mass consumer adoption but not a barrier for business users, said Yamamoto, and right now a lot of business applications are being developed that make use of the technology, he said.

NTT Data, one of the key members of the 3DC, has a large amount of mapping data of Japan and is working on ways to represent it in three dimensions. Applications in medicine are also envisaged and Yamamoto reports that doctors who have seen data from scans assembled into a 3D image are impressed with the technology.

Back in the consumer market content remains a problem although NEC is trying to entice buyers with a 3D version of the popular Final Fantasy game. Getting more content on the market remains a prime goal of the 3DC too and several software companies, including Namco are Microsoft members.

Entertainment content in 3D might be available soon in Japan. A new satellite broadcasting service due to launch in the middle of this year by Mobile Broadcasting Corp (MBCO) will beam video to small handheld devices, and Sharp is considering the development of a terminal with 3D display and the provision of some 3D programming, said MBCO.

Another consortium member, Dynamic Digital Depth, is working on adding an additional dimension to existing 2D. It's a time-consuming job as the first and last frames of each scene have to be manually coded with depth information to indicate which objects are in the foreground and which are in the background. A machine then takes over for the other frames in a scene but these all have to be checked and then the same is done for the next scene. In something like a music video with lots of cuts between cameras it takes a long time, said Theresa Roth-Borunda, a spokeswoman for the company.

She estimates turning a 10-minute video clip into a 3D image takes around a week.

The other solution is to create the content in 3D from the start and that's how 3D will take off in the consumer space, estimates Yamamoto. A number of digital camera makers are part of the 3DC and one of them, Pentax, is already selling cameras that can take rudimentary 3D images.

Steven Smith, a research specialist with MIT's Media Laboratory, is dreaming beyond today's displays and thinking about even more advanced 3D imaging. His group is working on displays that maintain the full resolution of an image while displaying it in three dimensions.

MIT is working to create a display that lets multiple users view 3D images without having to stare at one portion of the screen or view images of poor resolution. Their technique requires a fast processor to refresh an LCD screen about twice as fast as current screens are capable, Smith said.

These displays are called full resolution autostereoscopic displays. A viewer can move their head from side to side, or get up and walk around, and the image will still appear in three dimensions. The trick is to refresh the images at speeds incapable of detection by the human eye, so multiple viewing areas can be created with no impact to resolution or the viewer's position.

The processing power is already here to allow this to happen, Smith said. Graphics card manufacturers such as NVidia or ATI already make some of the most sophisticated and powerful graphics technology in the world, but most of their customers can't take advantage of their full potential due to CPU or memory bottlenecks.

Likewise, display technologies are not yet sophisticated enough to accept images at the speeds required to enable autostereoscopic 3D images, Smith said.

He acknowledges the timeframe for this technology extends into the future, but isn't worried about how long it might take.

The 3D display industry has already evolved from researchers and hobbyists building products in their garages to companies that are submitting prototypes at conferences and trade shows, Smith said. The PC industry grew much the same way.

The next step beyond 3D imagery is the projection of holographic images, where the viewer could walk in a circle around an object and see detail from all sides. Once screen resolutions improve to a certain point, 10,000-x-3,000 pixels for example, this technology will extend to the entertainment and design engineering worlds, Smith said.