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Invisible Cloaks, Translucent Walls
jd writes "The University of Tokyo has developed the illusion of invisibility, under the name of 'Optical Camouflage.' The system is remarkably simple - you have a mix of light-sensitive and light-emitting devices attached to an adapted reflective surface. The devices are hooked to a computer, which simply projects on each side whatever is on the opposite side. The result is more of a translucent look, than real invisibility, but the potential is there. The inventer's next objective is to make walls that are invisible, using the same technology. Project a real outside image onto an interior wall without windows. This almost sounds more frightening than the cloak, since there's no reason why the sensors would have to be placed outside. Imagine a world where PHBs can turn their office wall into a window onto any cube. Zero privacy. The technology is great, but the potential for abuse is definitely there." Update: 06/15 00:20 GMT by T : You may remember we mentioned this project when it was cloak-only.
It requires an image to be project on the material.
Actually it's worse than that. It requires the image be projected from the onlooker's point of view. That's what they mean by HMP (==head-mounted projector) So for army dudes to use this, they'd have to actually run up to the enemy, and surreptitiously slap a projector on the head of each bad guy they wanted to hide from, then run back and go about their business of avoiding detection. There's probably a greater liklihood of success basing your military tactics on lethally funny jokes.
In Susumu Tachi's cloaking system, a camera behind the wearer feeds background images through a computer to a projector, which paints them on a jacket as though it were a movie screen. The wearer appears mysteriously translucent - as long as observers are facing the projection head-on and the background isn't too bright.
To Achieve true invisibility, optical camouflage must capture the background from all angles and display it from all perspectives simultaneously. This requires a minimum of six stereoscopic camera pairs, allowing the computer to model the surroundings and synthesize the scene from every point of view. To display this imagery, the fabric is covered with hyperpixels, each consisting of a 180 x 180 LED array behind a hemispherical lens. This is fantastic, although I'd rather drink a potion.
http://www.kevinrewatts.com/filter/archives/2003_0 7.html
I survived the Dick Cheney Presidency 7 to 9 AM 7-21-07
I saw the cloak demonstrated last month and talked to the U. of Tokyo people who were showing it and I have to tell you: this is about the lamest thing ever.
THERE IS NO TECHNOLOGY THERE AT ALL!
It's a grey cloak. That's it. A grey cloak. You look at it, and it's a grey cloak. Nothing special at all. But no, "please look at the video monitor!"
Oh, in the video monitor the cloak is sorta transparent. Why? Because they're doing an absolutely standard compositing effect IN THE VIDEO MONITOR.
The cloak is NOT transparent. It's just a piece of blue screen and they composite the background on it. But only if you look at a video monitor. In real life, the cloak is entirely opaque and it's just a grey cloak.
I asked the professor how long it would be before they had a real working prototype and he said "Maybe 20 years."
In other words, they have nothing. Just a concept. And it's not even a new concept. It's an old science fiction concept.
There is nothing to see here. It's just PR and a very standard old-hat video effect.