Scientists making 3-D telepresence a reality
By Margaret Munro, Postmedia news November 3, 2010 2:25 PM
http://www.montrealgazette.com/news...ence+reality/3771600/story.html#ixzz14FKpbqTP
R2D2 would be impressed. Thirty-three years after he helped Princess Leia's make an impassioned plea from afar in Star Wars, scientists are making 3-D telepresence a reality.
"It is no longer something that is science fiction, it is actually something that you can do today," says Nasser Peyghambarian, leader of a U.S. team that is busy sending 3-D moving holograms of Phantom jets and people from one location to another.
"We have demonstrated the concept and it works," says Peyghambarian, whose optical science team at the University of Arizona describes the new system in the journal Nature on Thursday.
He and his colleagues say it is not quite ready for prime time. The "holographic telepresence" is limited to images 43-centimetre high, which is about how big Princess Leia's telepresence was in the iconic Star Wars scene. Color is also limited and the holograms' movements are halting as it takes two seconds for them to "refresh".
But Peyghambarian expects that within a few years life-size, full-colour, high-resolution holographs of people and objects will be popping out of tables and walls in research labs. And within seven to 10 years, he predicts they could be popping out of conferencing, medical, design and entertainment systems.
The people and objects will look real, Peyghambarian says, but if you try and reach out and touch them they'd be "nothing there."
Several companies are racing to produce 3-D television and conferencing systems so people can attend virtual meetings, reducing the need for travel and time away from home.
But sat Peyghambarian says most systems use just two perspectives, while the holographic telepresence has 16 and does not require 3-D glasses. His team is aiming for hundreds of perspectives showing objects and people from all angles, which is much closer to what the naked eye sees in the real world.
"I don't think there is any fundamental physics that would prevent us from getting there," he told reporters in a webcast this week.
At the heart of the new system is a multicolour, holographic display that refreshes every two seconds and gives the effect of quasi-real-time updating, using a new " photorefractive polymer" as the recording material. The images are taken by regular cameras at multiple angles in one location and sent to another location using Ethernet communication and then projected with the help of lasers on the computerized hologram set-up.
The prototype described in the Nature paper had a 25-centimtre screen, but Peyghambarian's says they now have a 43-centimetre system up and running. It uses 16 cameras to photograph objects from different angles. The more cameras used, the higher the resolution of the holograph, says Peyghambarian, who says an array of cameras in his Tucson office and a fast Internet connection would enable him to give a tele-presentation in New York.
"At the other end, in New York, there would be the 3D display using our laser system," he says. "Everything is fully automated and controlled by computer. "
The system has what the scientists call "full parallax: "As you move your head left and right or up and down, you see different perspectives. This makes for a very life-like image," says Peyghambarian. "Humans are used to seeing things in 3D." There is also an audio option so lifelike holograms could speak and interact with audiences.
The researchers, have patents pending on both the material and optical system, and are particularly keen on the possibilities for telemedicine. "Especially for brain surgery, surgeons at different locations around the world can observe in 3D, in real time, and participate in the surgical procedure," they conclude in their paper.
Lead author Pierre-Alexandre Blanche says that along with 3D medical imaging, another early application might be in the " military for command and control 3D battle maps" and holographic advertising.
"The next step will be to have a smaller, faster display to interest the entertainment market,' he says, noting that there is " still some hard work" before that happens.
