http://www.airforcetimes.com/news/2008/06/airforce_ghost_imagery_062908/

Discovery may make ghost imaging a reality

 

Three scientists believe they have discovered a method to make an image of an object without aiming a camera or sensor directly at it. And that could eventually allow Air Force satellites to photograph images on Earth through clouds, according to Yanhua Shih, a scientist at the University of Maryland, Baltimore County.

Scientists call it ghost imaging. The premise of this process, based on quantum mechanics theory, is that one image can be built by using a digital camera to collect light — photons — from a light source, using a light meter to collect photons bouncing off an object and then pairing them to develop a black and white silhouette of the object.

Ron Meyers and Keith Deacon — who work at the Army Research Laboratory with Shih — are the first to demonstrate ghost imaging of opaque objects in a recent experiment, partially funded by the Air Force, in which they photographed a toy soldier.

Instead of aiming a camera at it, the scientists pointed it at the light source — a chaotic laser shining on the toy. They aimed a sensitive light meter at the toy.

Albert Einstein explored the basic research behind ghost imaging — quantum entanglement — which he called “spooky action at a distance” in 1935. Shih discovered ghost imaging in 1995, but the theory has yet to leave the laboratory.

Air Force satellites could use ghost imaging by pointing a light sensor toward the Earth’s surface and another toward the sun. The technique could allow the service to penetrate clouds or the smoke that follows airstrikes.

Shih said he’s spoken to Air Force officials about connecting ghost-imaging sensors to helicopters or unmanned aerial vehicles to get images measuring the extent of the damage immediately after a bomb is dropped.

Defense manufacturer Lockheed Martin has shown interest in quantum entanglement, acquiring a U.S. patent in May to develop quantum radar that could defeat stealth aircraft and find camouflaged improvised explosive devices and mines, according to the patent.

Further research into ghost imaging could also lead to new methods to develop high-resolution photographs, Shih said.