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How To See Through an Invisibility Cloak

Posted by timothy on from the very-zen dept.

AMESN writes "Ways to bend light around objects and render them invisible are becoming a major field of scientific study and gaining ground. While no actual invisibility cloak exists yet, researchers are also theorizing on how to beat the perfect cloak."

7 of 201 comments (clear)

  1. rain by wizardforce · · Score: 5, Insightful

    No invisibility cloak can hide the fact that it's still a solid object. That or utilize various frequencies of EM as it would be extremely difficult to defeat radar + infared + visible + UV all at the same time.

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    Sigs are too short to say anything truly profound so read the above post instead.
    1. Re:rain by Penguinisto · · Score: 3, Insightful

      Exactly. Even the vaunted "stealth" technologies of the 1980's and '90s were engineered only towards a certain set of frequencies.

      This 'invisibility cloak' could be defeated as easily as using a video camera with "night shot" built in (basically, an infrared emitter on the camera body sends out IR, and the lens picks that up, making it a bit more active than simply taking in whatever it sees). The cloak blocks the IR, so it'll either shine with the reflected waves or will show up as a shadow.

      Other ways to defeat it? Talcum powder or other particulates (like rain ferinstance).

      'course, I doubt that they could make such a "cloak" anyway, at least insofar as it would still show movement. So unless their 'spy' is really good at standing still, he's still liable to be noticed.

      --
      Quo usque tandem abutere, Nimbus, patientia nostra?
  2. You can't beat the perfect cloak... by unitron · · Score: 5, Insightful

    If you can, it's not perfect.

    The real problem isn't detecting it. It's knowing that you need to be trying to detect it in the first place, and approximately when and in what area.

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    I see even classic Slashdot is now pretty much unusable on dial up anymore.

  3. Why worry? by gmuslera · · Score: 3, Insightful

    A perfect invisibility cloak is also a perfect blindness cloak. Unless you make i.e. missiles or bullets (dodge that, Neo!) with it, things with a predefined target, could be somewhat useless for most interesting uses. The imperfect are the useful ones.

  4. Re:It's been proved impossible using negative ior by sopssa · · Score: 3, Insightful

    I am not sure why people are being so slow to accept this.

    Because nothing in world has to be 100% perfect. It just has to work good enough. And maybe later there will be new discoveries that will improve it. That's how technology and science has always worked.

    Sure, there will always be ways to get around the invisibility cloak, just like people have ways to get around DRM. But it doesn't make it completely useless or non-working technology.

  5. Invisibility by NoobixCube · · Score: 4, Insightful

    An "invisibility cloak" these days doesn't just necessarily apply to the visible light spectrum. The cloak could be a thermal or radar "invisibility" cloak, leaving an object perfectly visible to the naked eye, but invisible on other scans. Penetrating thermal invisibility cloaks might end up more important, because camouflage can take care of visible light from overhead, it's the thermal that's the giveaway.

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    Admit it. You post strawman arguments as AC so you get modded Insightful for refuting them, rather than Troll
  6. Re:The easy solution, from the article by Idiomatick · · Score: 4, Insightful

    I imagine throwing a stone at something you don't know is there to find it would be quite the feat.