Invisibility Shields Planned by Engineers

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Electronic engineers at the University of Pennsylvania in Philadelphia are researching a device they say could make objects "nearly invisible to an observer." The contrivance works by preventing light from bouncing off the surface of an object, causing the object to appear so small it all but disappears.


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The concept is based on a "plasmonic cover," which is a means to prevent light from scattering. (It is light bouncing off an object that makes it visible to an observer).

The cover would stop light from scattering by resonating at the same frequency as the light striking it. If such a device could cope with different wavelengths of electromagnetic radiation (including visible light), in theory, the object would vanish into thin air.



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When light strikes a metallic material, waves of electrons, called plasmons, are generated. The engineers found that when the frequency of the light striking the material matched the frequency of the plasmons, the two frequencies act to cancel each other out.

http://news.nationalgeographic.com/news/2005/02/0228_050228_invisibility.html

eom

We'll just have to give up perfecting it once we sign that treaty with the Klingons and Romulans anyway.

Here's a more informative article appearing in Nature:

http://www.nature.com/news/2005/050228/full/050228-1.html

From the article: "And crucially, the effect only works when the wavelength of the light being scattered is roughly the same size as the object. So shielding from visible light would be possible only for microscopic objects; larger ones could be hidden only to long-wavelength radiation such as microwaves. This means that the technology could not be used to hide people or vehicles from human vision."

In other words, you see that thing you can't see because it's too small to see? Well, now we can make it invisible! Can we have our grant check now? And a couple of double pepperonis with double cheese. We get hungry working in this lab.

I'm working on making objects hard to see by placing them very far away. It's cutting-edge stuff, let me tell you.

After all, doesn't just painting something a nice, deep, matte black pretty much prevent us from seeing light reflected from the surface?

As Invisible Boy claimed: "I'm only invisible when no one's looking."

Many modern weapons sights use IR scopes to look for heat signatures coming from troops and vehicles for night combat. If you could mask the heat given off by troops and their weapons, that would be a huge improvement.

Then again, we're currently getting our asses whipped by Iraqis with 1950's-era technology, so maybe this wouldn't be so revolutionary after all.

So, based on what I read earlier, this wouldn't be able to mask troops and weapons unless they were really, really small.

--Peter

Sure, supposedly it stops any light from reflecting or scattering off of it's surface. what about objects in the far side? If you can't mimic the light emissions from those objects then all you've done is create an area with no light emissions whatsoever.

The existing radar stealth tech is all about reducing backscatter. This sounds like it would all but eliminate it. And it would be easier to tuen the surface to known radar-bands that are used by militaries, than to attempt tuning the surface to the entire visual spectrum.