Slashdot Mirror

← Back to Stories (view on slashdot.org)

Engineers Devise Invisibility Shield

Posted by timothy on from the impossibly-large-yellow-somethings dept.

GerritHoll points out an article in Nature according to which "researchers at the University of Pennsylvania 'say that a "plasmonic cover" could render objects "nearly invisible to an observer.' Earlier attempts at invisibility worked by colouring a screen to match its background, like a chameleon. The described technique is new, because it works by the concept of reducing light scattering. It is not a 'magic cloak,' however, because it will not work for the full range of visible light and needs to be adjusted precisely for the shape of the object. However, the concept could find an application in stealth technology."

6 of 316 comments (clear)

  1. Invisibility cloaking by kngthdn · · Score: 4, Interesting

    It is not a 'magic cloak,' however.

    Like this?

    Well, that actually requires a special viewfinder, so it's not quite as cool, but it sure *looks* awesome. Better than the "spot the spaceship" pic, anyway.

    How long til I can buy this stuff at Walmart?

    1. Re:Invisibility cloaking by kngthdn · · Score: 4, Interesting

      Here's an interesting article about it on the Scotsman.

      It says, Similarly, researchers in Tokyo are developing a camouflage fabric that uses a comparable principle where the background is projected on to light-reflecting beads in the material. Such systems are, however, dependent on the viewer from which the object is being concealed being in the right position.

      I see no mention of Photoshop, but it does say it could be used by surgeons and pilots. Sounds pretty cool to me.

  2. Obvious Applications by poopdeville · · Score: 4, Interesting

    I can think of a couple of obvious applications, especially if the technology can be adapted to scatter microwaves. Tanks and mechanized infantry are pretty obvious, but I think we want to avoid battleships unless we want a repeat of the Philadelpha Experiment and the crappy movie versions (though I loved the first one as a kid).

    But what about non-military uses? Perhaps a "coat" of plasma on windows to reduce cooling bills in the summer? Or another coat of plasma on TV's to reduce glare? I can't think of anything particularly inspiring.

    --
    After all, I am strangely colored.
  3. The shadow effect by Dikeman · · Score: 5, Interesting

    The article puts two techniques next to eachother, as if it were alternatives for the same problem. This is false.
    The proposed system with plasmonic covering reduces the scattering of light. The lightwaves pass by the object as were the object very small, smaller than it actually is. Hence it only works with objects that are allready very small, because otherwise the object would cast a shadow. (Light passes by, not through)
    The system with light detectors and emitters mimics the scene that is behind (bigger) objects with respect to the viewer. You could actualy say that it fills in the shadow cast by the object.

    So were the first system reduces the shadow effect, the second replaces the shadow alltogether. I could actualy see these two systems used along side eachother rather than instead of eachother.

  4. front projection by Metryq · · Score: 5, Interesting

    The Japanese "invisibility cloak" is nothing more than the front projection technique used in 2001: A SPACE ODYSSEY and many other films. That's like claiming that we have a super weapon that can hit an enemy anywhere -- provided he stands right here on this spot marked X. The alleged surgical and pilotting applications sound equally silly. It is an infinite regression of "if we can fit a camera in front of the surgeon's hands, we can project an image behind them to make a really cool effect that they are invisible!"

  5. Re:Indeed, it's pretty far from advertised... by bw_bur · · Score: 4, Interesting
    This wouldn't work. The radar would pass through the molecules, only to reflect off of the aircraft skin

    Exactly. Hopefully someone will mod you up...

    Now, if it could be set up so that the radar would pass through once, and bounce around between the skin and the coating before finding the right angle to escape, it would probably make the radar bounce off the plane at all kinds of weird angles (making the radar useless).

    The problem I'm wondering about is: What happens if the radar can't find a way out? Will it keep bouncing around, loosing energy all the while, heating up both the skin and the coating (this may become an issue)?

    These are the two conventional approaches to stealth: either deflect incoming waves anywhere but back towards the detector, or absorb as much as possible, in which case the coating inevitably heats up. I don't think this is much of an issue though: probably much more heat is generated simply by flying at high speeds.