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Cloak of Invisibility Coming Soon?
Chris writes "The idea of an "invisibility cloak" has made the leap from science fiction books to an international patent application. The "three dimensional cloaking process and apparatus" for concealing objects and people (WO 02/067196) employs photodetectors on the rear surface which are used to record the intensity and color of a source of illumination behind the object. Light emitters on the front surface then generate light beams that exactly mimic the same measured intensity, color and trajectory. The result is that an observer looking at the front of the object appears to see straight through it."
...what's the bonus to saving throws when wearing it? :)
--Kylus
Idiot-proof something, and Life will build a better Idiot.
There are many angles crossing an object, although this may work for simple front to back (as the article states)
I don't think it is that workable for all directions, or even more then a few.
The problem with this device as it's designed so far is that it only works when looking straight at the object.
In addition, I have serious questions about the resolution of the device (how many sensors and how many light emitters). Will the person look "pixelated" and or will there be some other problem.
Lastly, such a device is not useful in combat situations as many soldiers in such a ground war situation will be outfitted with infr-red detectors, which will probably be able to detect the human behind the suit.
Good idea but has a lot of practical problems (we haven't even discussed the power source).
I suspect that the squeaking of the wheelbarrow that you'll need to carry the batteries, fuel cells or magic moonbeams that'll be needed to power this thing will render any invisibility firly useless.
But I still want one, go figure
Get the EULA T-shirt
I'll be more impressed when a Cloak of Charisma is released; hellloooo, laydeez|boyz!
(and no, those new cargo pants you just bought from Gap do not count).
----- Documentation is worth it just to be able to answer all your mail with 'RTFM' - Alan Cox.
Most readers of Slashdot already have one of these. Problem is, it only works on women.
Naked Woman: Actually, I can see a shimmery shape, because you're slightly off-center to me.
PWTHI: Wait, wait, you're not in the right place. Move to the left.
NW: Ok. Now you're even MORE shimmery
PWTHI: No, no, MY left, not your left
NW: Oh, sorry. There, the shimmering went away.
PWTHI: Ha ha ha ha!!!! I can see you naked!!
NW: Sir, this is a strip club. It's not exactly difficult.
Instead of making me invisible, I just want it to make me look thinner. Shave off my side edges by painting the background over my sides, and voila, I've lost 20 pounds.
What's your damage, Heather?
This has been done before using fibre optics, I believe, so that you would effectively see through the person because they wore an outfit consisting of thin fibre optic wires routeing light straight through them. This was on TV once, although I don't know whether it was the actual suit being shown or merely some special effects to show what it _could_ look like. Either way, it looked obvious that there was someone there - anything longer than a brief glance would be time enough to tell.
Like car accidents, most hardware problems are due to driver error.
I believe in WWII some submarine hunter aircraft had spotlights on the front to make the apparent brightness of the dark aircraft match the sky. Killed more subs that way.
this technique worked really well for large objects if they were a good distance away, like for a tank of the horizon or an aircraft in the sky. awful for close up work.
I recall a good article on this someplace on the web, but to find it now on short notice .....
"It is a greater offense to steal men's labor, than their clothes"
What, no pictures?
It's 10 PM. Do you know if you're un-American?
Whew!... just imagine if this technology had been developed before our ability to uncloak terrorist networks.
The evaluation of an action as 'practical' . . . depends on what it is that one wishes to practice.
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For looking straight at the object: just coat the whole thing in emitters and detectors. That's not a big fundamental problem. You don't want light reflecting off the object anyway; might as well have detectors that absorb it.
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The resolution problem can be addressed simply by increasing the resolution until it's small enough not to be noticable. Regardless, even at low resolution, it's better than normal camouflage, isn't it? (Ever seen Predator?)
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The infrared problem can be solved the same way the visible light problem is solved. Just have IR detectors and emitters. You can even to a variety of frequencies (just as with visible light) to fool various enemy equipment.
To me, a big problem would be to counter an active detection system that shines light on the object and looks for reflections. The emitters will be subject to a design trade-off between emission and absorption, and it might be hard to find a technology that does both well enough.Patrick Doyle
I mod down every jackass who puts his moderation policy in his sig. Oh, wait a sec....
My completely uneducated guess is that the object will appear a lot like those "magic eyes" pictures that were all the rage a few years ago...
i.e. when you move from side to side (or up/down) the object will shift at a slightly different rate than the background, and your senses will detect something. you may not be able to tell what it is, but something will feel "off". I'm sure at greater distances the effect will be less, and therefore the technique will be more useful.
Reminds me of Predator, and the way that it shimmered when it moved. My guess is that they used the same thought when they made that movie.
Very cool.
No man is an island, but Gary is a city in Indiana.
The article very definately uses the words "detect" (light behind) and "generate" (image in front). This implies it is not some passthrough technology (fiber, etc), but an electronic record and recreation.
If this "clock" could live up to its claims, there are three (possibly more) far more interesting applications that must be considered:
Given that researchers would be coining it from more down-to-earth inventions like these, I can't really see that the technology - as described - exists or is being developed.
i-name =twylite [http://public.xdi.org/=twylite], see idcommons.net
The most important part of camoflage is making recognizable features hard to see -- hands, faces, etc -- things our visual system is hardwired to pickup out of the background. This invisibility cloak would do that.
I imagine it looking like the Alien in that Arnold movie, hard to see unless it's moving and then the distortions give it away.
Of course is this a really old idea -- heck it a similiar idea was in comics in the 1970s (some super heros club house had this kind of device to hide it from view).
...when I see it.
Sorry, it had to be said.
This is a pretty near perfect example of a bad patent.
1) the idea is pretty obvious (as well as many references in common SF literature)
2) the actual implementation with current tech will be pretty miserable. Put big bright light behind object, make object shine big bright light at viewer. Viewer is blinded by both and as object is indistinquishable the technique is easily demonstrated to the patent requirement level.
3) it serves as a patent stake. Further research into a better/improved technology will have to deal with this patent.
This is a near perfect bad patent that grants the patent holder a big stake in the ground for actually showing very little. And any future work that will actually improve the technique is going to have to deal with the patent.
Even if this intended to be just one way. You'd have to have very little light coming from the direction of the intended person to be "blinded." This would assume that this cloak will absorb *all* (up to a point that's observable) the light that would have reflected off of it and to the observer. Well, perfect black body's just don't exist. There'll always be likely to have a reflection come off of this thing.
/me wanders away.
That's just the beginning, I don't think we're anywhere near having what's essentially an instantly recorded and rebroadcast super high resolution wrappable screen. The way, though I could be mistaken, that most light sources are created even in high definition display devices, will allow for scattering, so the image you would see where the person should be would be blurry. You'd have to get pretty close to duplicating every photon. Not nearly so accurately of course since the human eye isn't so good, but still.
Anyway, I'm just stupid.
Many have already pointed out the most obvious problem -- any angle other than straight on is going to wreck the effect. But let's not forget that a human with two functional, open eyes never views an object from just one angle (unless one eye's view of the object is obstructed -- geez, picky...). Ah, the miracle of depth perception. I don't think this method is nearly sophisticated enough to compensate for all the subtle clues we get from our binocular vision. Nice try, though. I mean, I think that everyone who's considered the possibility of invisibility has come up with a scheme like this. It's nice to see it coming closer to reality, but we all know that at this stage it's too limited except for perhaps certain special circumstances. But yeah, I want one too.
My deviantArt site
It also doesn't do much for your heat signiture. Since so much military surveillance is done with IR, you'd think that the extra heat generated by the thing being cloacked and the cloaking mechanism that it'd glow like a light bulb under IR.
I mean, its not as high tech, but its a lot cheaper.
...is an amusing century-old story about competitive brothers who devise two different methods of achieving invisibility. It's online here.
In his fictional story, both methods have problems. The problems are more than fictional, since one of the methods relies on the nonsense supposition that since black is the absence of light, the only reason you can see something that's black is that the black isn't PERFECTLY black, and that if you could achieve perfect blackness you could achieve invisibility.
However, the method described in the parent article here is equally flawed, since it would work only for an observer placed in a specific view location. One wonders how the equipment is supposed to locate the observer; if there are several observers, how does it decide which of them should be prevented from seeing the object?
The method bears a close resemblance to Hollywood special effects processes (glass shots, matte shots, etc.) Special effects processes are notorious for having visible edge effects if not done carefully, and I'm sure this would be true of the proposed method as well.
In "The Shadow and the Flash," one invisibility cloak could be detected by a sensation of darkness and depression whenever the concealed individual was nearby; the other suffered from occasional rainbow flashes due to mismatches in the index of refraction. I'm sure that the proposed method would have similar problems.
"How to Do Nothing," kids activities, back in print!
Only a patent
Haven't you been reading any other articles lately? Only a patent? You mean like Amazon's "one click" patent? Like BT's patent of hyperlinks? Compuserve GIFS? A laser pointer as an exercise device for a cat? The patent on a swing?
No, it's not a new idea. The military has been playing with it for years. Deep sea fish do it naturally with bioluminesence. If they get a working model, then ok, give them a patent. But I'd hate to see another ridiculous patent granted on an idea that's been around for decades.
-- If god wanted me to have a sig, he'd have given me a sense of humor.
How about a house with sensors on the outside walls, and the projectors on the inside?
It would be like being outside, except the outside couldn't see or get in. And I'm sure it probably wouldn't transmit uva/uvb, so no sunburn. Imagine, no more sky windows. The ceiling could be the sky, complete with clouds. (Of course you could control the briteness, turn it off/on, etc.)
This could even replace windows in buildings you'd want more secured or where glass is a structural liability.
I don't see it being patented, as the thought of an image being, essentially, transfered from what is behind something to in front of an object has been discussed for eon's (or at least years). The process, however, is a lot more difficult than at least mentioned in the small news clip. You're right about blocking light behind it, in relation to the Mona Lisa.
But I believe there's a third item which comes into play. For us to see something, there are three variables involved. The source (and intensity) of the light, the object itself (and how it reflects the light) and our eyes, upon which the light falls, for us to see the image. The 'image' or the object we all see, varies to a degree based upon there we stand. To 'cloak' simply using the process mentioned cannot overcome the fact that we all observe the object differently if we're each standing in a different place, and that doesn't seem to be taken into consideration. The simpliest part of the viewers position (though there are many), is the part of depth perception. If we're three feet from the wall behind the object, and two feet from the Mona Lisa, then 'cloaking' the Mona Lisa has a 'wall', a portion which is displaced from the real one, 'appear' other than in the same plane as the real wall. Part will look further away then the part of the wall that is closer (the cloaked Mona Lisa), because the light will be generated/reflected from a different distance from the 'real' wall. One MIGHT be able to compensate that difference by altering the output and seemingly making the object, but hues/density, etc, seem elsewhere... exactly where the real wall is located. But that works one person standing in exactly the same spot for which the compensation is calculated. A person 10 degrees offset sees a different perception...I don't see how one compensates for that.
If the object is an extreme distance where depth perception is essentially nil or in a dim setting there depth is also less acute, then it is more 'believed' by the viewer. Otherwise, as long as one has two eyes, I see a problem.
...a productivity cloak.
Imagine it. You're having a lousy day at the office. Got nothing done, but read email. Your boss comes storming in asking for a report that's 2 months overdue. You simply throw on your productivity cloak and (walla!) your screen shows a nearly completed report, while you appear confident it'll be done soon.
managers...why god invented purgatory
More likely, they were just thinking that a truly invisible creature didn't make for very scary film footage.
He looked at me and said, "Kid, we don't like your kind, and we're gonna send your fingerprints off to Washington."
Now that they have solved the tall guy sitting in front of you in the movie theater .... Now they just need to solve the jerk sitting behind you kicking your seat.
In his fictional story, both methods have problems. The problems are more than fictional, since one of the methods relies on the nonsense supposition that since black is the absence of light, the only reason you can see something that's black is that the black isn't PERFECTLY black, and that if you could achieve perfect blackness you could achieve invisibility.
And the other process was to make the subject transparent. Would work if possible but also impractical.
But a "cloak" that either records the view on one side, small patch by small patch, and reconstructs it on the other side ditto, or actually pipes the light around and re-emits it, has been used repeatedly in science fiction since the Golden Age of Campbell's editorship of Astounding/Analog magazine.
I THINK some of 'em even got the need for networking each "camera" to multiple "displays", to account for the virtual passage of light through the thickness of the cloaked space, though I don't recall any of 'em explicitly mentioning the need for the network connectivity to be dynamic, to account for a flexing body.
(I'd dig through my collection to find a few samples but it would take a while. If you want to dig through yours, start with Randall Garret.)
Now if somebody has come up with a particular WAY to pipe the light or its signal around that's worthy of a patent. But if they've just patented the idea of mimicing a transparency (light emission) or do what an octopus does (variable absorbtive color cells to mimic the surface behind), it's been described repeatedly.
An aside: One of the funnier throwaways in a fantasy novel (Too Many Magicians?) was the presentation at a magician's conference of a spell for making EVERYTHING BUT THE EYES invisible. The disadvantage of the previous spells was that they made the subject blind, because the light didn't interact with his eyes. It is easier to hide a floating pair of eyes than a whole body, and easier to be unnoticed if you aren't constantly bumping into things. B-)
Bantam Dominique roosters crow a four-note song. Once you've heard it as "Happy BIRTHday" you can't NOT hear it that way