The invisible man

Technology Review has an article on the next generation of camouflage:

digital cameras that can capture nearby surroundings and then project that scene on uniforms and vehicles, turning the military into a mobile movie screen that is — if all goes well — indistinguishable from the surrounding cityscape.

As a parlor trick, it's been demonstrated at conferences. Mount a camera on your back facing backwards, and hook it up to a laptop that you carry in front of you with the screen facing the audience. The part of you that is covered by the laptop screen seems to be invisible because the screen shows what's going on behind you.

But converting this to real camouflage that works in 360 degrees and from all angles it a bit more complex.

The biggest challenge: working out how to accurately project a scene onto an entire surface and have it look correct from any angle -- not just from the front -- because there will always be multiple viewers in multiple positions who would be looking hard in the general direction of your invisible army, says Col. James R. Rowan, commander of the U.S. Army Engineer Research and Development Center in Vicksburg, Mississippi. …

"It's a big investment in technology, and after all that the invisibility could be easily circumvented with a thermal imaging system or a paint bomb," says retired optical engineer Frank Kennedy. …

NASA engineers who have worked on active camouflage projects before funding was pulled several years ago cited shadows as the biggest problem in creating invisibility. To be truly hidden from above, noted the NASA scientists in their project paper, an object needs to cast the appropriate shadow.
"Proper shadows will be real hard to pull off when you have a tank camouflaged as part of a city block," says Kennedy. "It's the little details that cause the biggest problems."

This article from 21st Century Online describes similar work by Dr. Susumu Tachi of the University of Tokyo. The example picture (shown above) doesn't seem to me to reach the level of invisibility. But it's a start.

The picture was published in a number of newspaper stories in March 2003. Perhaps technology has improved since then. It's certainly an intriguing idea.