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Acoustic "Superlens" Could Make Subs Invisible

Posted by kdawson on from the bending-it dept.

Al writes "Nicholas Fang and colleagues at the University of Illinois at Urbana-Champaign have created the first acoustic superlens, which could be used to create high-resolution ultrasound images, and perhaps ultimately make subs and ships invisible to sonar. Researchers have previously developed materials that bend light in ways that appear to violate the laws of physics, creating so-called optical superlenses. The acoustic superlens consists of an aluminum array of narrow-necked resonant cavities filed with water — the dimensions of the cavities are tuned to interact with ultrasound waves. When ultrasound waves move through the array, the cavities resonate and the sound is refocused."

8 of 136 comments (clear)

  1. Re:invisible != inaudible by Arthur+B. · · Score: 4, Insightful

    No. They may still be audible, but ultrasound will appear to go through them as if they were water.

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    \u262D = \u5350
  2. Invisible to *active* sonar, maybe. by pushing-robot · · Score: 5, Insightful

    Passive sonar, on the other hand, still works fine.

    After all, the thing's got to have a tailpipe.

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    How can I believe you when you tell me what I don't want to hear?
  3. Re:Save the whales! by Anonymous Coward · · Score: 2, Insightful

    Oh noes! Teh whales! You're right - the entire western Navy should just pack up and go home. I'm sure our enemies, being the reasonable and thoughtful people they seem to be, will follow suit.

  4. Re:Save the whales! by Anonymous Coward · · Score: 1, Insightful

    I think there's room for the GP on Obama's cabinet! Mr. Prez seems to like people who make knee-jerk decisions/comments without thought to their long-term ramifications.

  5. Violate the laws of physics? by Yvan256 · · Score: 4, Insightful

    Researchers have previously developed materials that bend light in ways that appear to violate the laws of physics.

    If they have developed materials that bend light in ways that appear to violate the laws of physics, then it means the laws of physics need to be redefined. That's what science is. Formulas made from observations. New observations may modify your existing understanding of how things work.

    And if you can't accept that, you shouldn't call yourself a scientist.

    1. Re:Violate the laws of physics? by MozeeToby · · Score: 2, Insightful

      The key word here is 'appear'. Meta-materials (which is what this is, just on a large scale) appear to violate the laws of physics but if you look more closely they don't. The point is that if you showed it to a college undergrad with decent physics knowledge they would say it violates the laws of physics, that doesn't mean the college kid is right.

  6. Re:This brings up an important point by Ninkazu · · Score: 3, Insightful

    The trivial solution would be a cavity filled with water same shape and size as the submarine, at the same position as the submarine.

    Why is this marked interesting? Clearly it's funny, since the above suggestion is to have the so-called submarine actually just be a pocket of water. i.e. no submarine.

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    The one true Ninkazu.
  7. Re:This brings up an important point by Nethead · · Score: 2, Insightful

    Most 3 digit ID posters have long ago stopped worrying about karma.

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    -- I have a private email server in my basement.