More than 30 years after the famous Star Wars movie scene in which a hologram of Princess Leia appealed for help from Obi-Wan Kenobi, US researchers have unveiled holographic technology to transmit and view moving three-dimensional images.
The scientists at the University of Arizona say their prototype “holographic three-dimensional telepresence” is the world’s first practical 3D transmission system that works without requiring viewers to wear special glasses or other devices. The research is published in the journal Nature.
Potential applications range from telemedicine and teleconferencing to mass entertainment.
“Holographic telepresence means we can record a three-dimensional image in one location and show it in another location, in real-time, anywhere in the world,” said Nasser Peyghambarian, project leader.
Existing 3D projection systems produce either static holograms with excellent depth and resolution but no movement – or stereoscopic films, such as Avatar, which give the perspective from one viewpoint only and do not allow the viewer to walk around the image. The new technology combines motion with an impression of genuine solidity.
The heart of the system is a new “photographic” polymer developed by the California research labs of Nitto Denko, the Japanese electronic materials company.
A 3D image is recorded with an array of cameras, capturing the object from different positions, and is then encoded digitally in a fast-pulsed laser beam, which creates holographic pixels or “hogels” in the polymer. The image itself results from an optical interference pattern between two laser beams.
The prototype device has a 10-inch monochrome viewing screen and the picture refreshes every two seconds – much too slow to convey natural movement.
But the researchers are confident that, now they have proved the concept, it will be possible to develop a full-colour system large enough to capture the human body and fast enough to give smooth movements. Professor Peyghambarian said it would take at least seven to 10 years’ work before a consumer version of the system was ready to test in people’s homes.
The technology is insensitive to vibration and could be used in noisy industrial environments for product design and manufacturing.
Telemedicine, especially for brain surgery, is another application put forward in the Nature paper. “Surgeons at different locations around the world could use the technique to observe in three dimensions, in real time, and to participate in the surgical procedure,” the researchers say.
Prof Peyghambarian was enthusiastic about teleconferencing. “Let’s say I want to give a presentation in New York,” he said. “All I need is an array of cameras here in my Tucson office and a fast internet connection. At the other end, in New York, there would be the 3D display using our laser system.
“Everything is fully automated and controlled by computer. As the image signals are transmitted, the lasers inscribe them into the screen and render them into a three-dimensional projection of me speaking,” he said.