Researchers Develop Purely Optical Cloaking 59
Rambo Tribble writes: Researchers at the University of Rochester have developed a remarkably effective visual cloak using a relatively simple arrangement of optical lenses. The method is unique in that it uses off-the-shelf components and provides cloaking through the visible spectrum. Also, it works in 3-D. As one researcher put it, "This is the first device that we know of that can do three-dimensional, continuously multidirectional cloaking, which works for transmitting rays in the visible spectrum." Bonus: The article includes instructions to build your own.
Re: (Score:1)
It seems down for me as well.
They probably just forgot to turn the cloaking device off.
Ob. Klingon (Score:2)
So' ghuS!
Re:Cloaking (Score:5, Funny)
Better yet:
1. Invent Cloak
2. Write Story giving directions
3. get slashdotted
4. website becomes invisible.
Re:Cloaking (Score:4, Funny)
Not that new (Score:2, Informative)
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This. All they're really doing is using four lenses to move the light around the object, but it only really works if the object has to stay within a certain limited area. This technique would never work for something like Predator and certainly not for Romulan Warbirds.
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Maybe the really, really huge lenses were out of the camera shot.
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What you would do is mount your lenses on the object you're hiding. They would move along with it.
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And so instead you see a bunch of lenses moving around which are considerably larger than the object they're trying to conceal, and furthermore would only work if all of them are oriented towards one particular viewer (viewers off to the side wouldn't be subject to this illusion.)
In other words, the Predator's plan of catching Arnie would fail pretty fast once his rear most lens bangs into a tree, knocking the whole thing out of alignment. Maybe Arnie doesn't see the predator, but he sees a strangely warped
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If someone invents a device that can transmit information a fraction of a second into the past,
No. If someone invents a device like that, they will win the Nobel prize and transform our understanding of physics. Their name will go down in history, and perhaps yours too, for predicting it on slashdot. This, though, appears to be four lenses arranged in a slightly nifty way. It's certainly not a 'cloaking device' - although I expect the researchers wouldn't describe it as such anyway.
The problem here is that science reporting has deteriorated to the point that the journalist has to pretty much make thi
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I was just thinking that same thing. A reasonably titled 'cloaking device' would need to actively camouflage an object from detection. Limiting not only the viewing angle but also the viewing distance makes this more like an optical illusion or magic trick than the practically useful device the name cloaking device confers. A board covered in glue, then covered in dirt, being used to cover a hole in the ground could technically be called a cloaking device with such a ridiculously broad definition. Maybe mor
Re: Not that new (Score:2)
I'm wondering why someone has not taken a few dozen cellphones and surrounded a sphere just to show a proof of concept.
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That idea has long been an industry proof of concept. Same for using projectors and cameras to display the backing image on the other side of the cloaking material.
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but it only really works if the object has to stay within a certain limited area
Actually, it's even more trivial than that. As they explicitly say in the video, the object has to stay out of the central area. Why? because the central area is where you're focusing the light. Now if they would only take those four lenses, put them in a tube and 'cloak' an absorber around the focal point to remove stray light, they would have a marvelous invention. I suggest calling it a telescope.
Welcome to elementary optics class, now with Harry Potter themed experiments.
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Now if they would only take those four lenses, put them in a tube and 'cloak' an absorber around the focal point to remove stray light, they would have a marvelous invention. I suggest calling it a telescope.
It really only requires 2 lenses, but in both a 4-lens (do such refractors exist? seems overly complicated) or 2 lens telescope the "cloaking" is only one direction and relies on the fact that the thing being "cloaked" is out of focus.
Anyone with a big aperture telescope can see this effect quick clearly without any fancy staging/setup at all. Simply look through the telescope at a distant object and then put your finger in front of the objective aperture. The only thing you will see is a very slight dim
I had a similar idea as a kid... (Score:2)
You know what an endoscope is, right? If not...google it and then read this again. Now...imagine you have a million strings of fiber and utilizing the same technology as with an endoscope, filling each sides with a lens just like the endoscopes work, you should (at l
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It would be one directional.
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MindPrision wrote "endoscope", but I believe he meant "fiber optic." Glass optical fibers should work both ways just fine.
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Re: I had a similar idea as a kid... (Score:2)
The simple fact is that the surface of a 3D shape can't be made to show the path of light through every part of that shape from every angle simultaneously without bending light.
Either it can only do so from one angle at once, meaning any other angle is inneffective, or it can show all angles through a point, and any other point is inneffective.
It is a simple terrestrial telescope (Score:3)
Amazing amount of cloaking! (Score:2)
This is beyond sad (Score:4, Insightful)
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Just like you, it only took a few seconds of video for me to be thoroughly underwhelmed. Why was this even made into an interview? This is extremely pedestrian.
The other, more advanced technologies are being developped in the aim of eventually creating objects that can cloak themselves. What are you gonna do, carry your gigantic lens array with you so you can be invisible? Well then you'll have a problem, cause people will see the lenses... Or you, if they just look at you from any angle that isn't sma
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What they have "invented" appears to be pretty ridiculous, yes, but you are attacking it from the wrong angle. What you are saying is that what they describe isn't suitable for a certain application, namely what you think when you hear "cloaking". Science isn't about finding applications, though, it's about making discoveries and understanding how nature works. There might be other applications that you can't think about right now, and if science would limit itself to what we now know is useful in some part
Impractical at any scale (Score:1)
Not only does it require a lens between you and the object, but it requires a lens behind the object as well.
You can do it with mirrors too! (Score:3)
Comment removed (Score:3)
Pictures or it didn't happen (Score:2)
Pictures or it didn't happen.
Acronym (Score:5, Funny)
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A complete blur on both sides. Since the light is extremely convergent, it won't make any sense to the eye.
These are the same optics in a telescope, by the way. If you were to look inside a telescope without the eyepiece, you'd get the idea right away of how it would look to be in the middle of this "new" idea.
Is cloaking really needed anymore? (Score:2, Funny)
Oblig (Score:2)
" I solemnly swear that I am up to no good... "