A little C&P (cut & paste) on 3D developments:
3-D Images, Without the Glasses
by Leander Kahney
3:00 a.m. 27.Feb.99.PST
A pair of British inventors have created the first cheap, workable computer screen that displays images in 3-D
without special glasses or clunky headgear.
In a field that has seen many impractical technologies, the inventors have achieved a simple, low-cost device
that creates a very convincing illusion of volume and depth.
"It makes people squeal with delight," said David Trayner, who developed the display with his domestic and
business partner Edwina Orr. "You get people grabbing at thin air. We had a 3-year-old trying to catch a figure
flying around in front of her -- she bashed her fingers on the screen. It's quite convincing."
Working out of a converted church in London's fashionable East End, the pair have crafted a hand-built
demonstration model from a standard LCD monitor held together by bulldog clips and sticky tape. They launched a
company, RealityVision, to bring the display to market. The first batch of displays will be manufactured later this
year, and if successful, the unit could be in mass-production within three to five years.
"It's one of the few systems that I've seen that could be brought to market," said Professor Nick Phillips of the
Department of Imaging Science at De Montfort University in Leicester, England. "Most of the stuff I've seen in this
field is rubbish."
Even more remarkable is that the system was invented by a pair with no formal engineering education. Sculptors
by training, the pair hold master's degrees from London's Royal College of Art. However, over the past 20 years,
Orr and Trayner have run a successful holography business, building large-scale, high-resolution holograms for
museums and scientific applications.
Trayner said it was their knowledge of holography that allowed them to create the breakthrough design of the 3-D
display.
"Holographers kick themselves when they see how it works, it's so bloody simple," he said.
Like 3-D movies viewed through colored glasses, the display exploits the principles of stereo vision, or stereopsis.
When slightly different images of a scene are presented to each eye, the viewers' brain stitches them together to
create an illusion of depth.
However, unlike competing displays that use a system of bars or directional filters to beam different images to
each eye, this screen uses a backlighting system inspired by holographic techniques to direct the different images
to the eyes.
Like a standard video signal, the images are interlaced and presented simultaneously: All the even lines in the
image are directed at one eye, all the odd lines directed at the other. As long as the viewer is in the right spot,
objects appear to hover anywhere from 8 inches in front of the screen to 16 inches behind it.
Trayner said the trick is in the optics; the display requires no special software or electronics. The display plugs
into a computer like a standard monitor and can double as a regular 2-D display.
As well as dispensing with glasses and headgear, the display is also free of the irritating image artifacts that
plague other systems.
"It's lacking in the nasties that would make you want to switch it off," Phillips said. "If it were a TV, members of
the family would be fighting for the best head position."
The images displayed can be live action or generated by 3-D modeling and animation packages. Instead of
recording the action with a single camera, scenes are filmed by a pair of cameras the same distance apart as
human eyes. The system splices the images together by using off-the-shelf software created for an earlier,
competing 3-D screen.
Using two cameras bonded eye-distance apart, they built a system for displaying live action in 3-D. Scenes can
easily be recorded and played back from standard videotape, Trayner said.
In theory, the display could be adapted to present 3-D images to several viewers simultaneously. It could also be
used to create a TV capable of beaming two different shows to viewers sitting side by side.
Trayner said they started dreaming up the design 10 years ago, started filing patents in 1992, and have published
a white paper on the technology. He estimated they invested about US$200,000 securing 50 worldwide patents
on the system.
The couple is in talks with a number of manufacturers, but like many new technologies, they face the
chicken-and-egg problem of getting units produced cheaply before momentum builds. Materials cost are negligible,
he said.
In the meantime, Orr and Trayner are in talks with companies in specialty areas like medical and scientific imaging,
computer-aided design, games, and of course, the military.
"We are very interested in it for medical use, and we were very impressed with the quality of the 3-D images,"
said Dr. Mel Levinson, chairman of Scion International, a Miami-based manufacturer of instruments for minimally
invasive surgery.
However, Levinson said there is some resistance in the 3-D medical-imaging community because of the poor
quality of past products. |
