Invisibility cloak!

[zznɟ ǝɥʇ]

Top Technologies That Cracked the Holy Grail of Invisibility

It seems scientists at the University of Tokyo have creaked a cloak that can more or less make the wearer invisible.

Hardly a few days back, Physicists figured out the complex mathematical equations for making objects invisible by bending light around them last year. Harry Potter fans will be delighted to hear the news. The design makes use of tiny needles to be fitted into a hairbrush shaped cone at angles and lengths that would force light to pass around the cloak. Some other researchers also tried to achieve the same but could only manage to hide objects in microwave spectrum. This is the first time that researchers have made an object invisible in a spectrum that is visible to human eye.

Full article is very interesting.

[William the Bastard]

YAY! This is just what the streets Britain needs. Invisible hoodies running around stabbing people and pickpocketing hardworking folk. Those scientists never think of the consequences do they! Other than that WOW! Where do I get one?

[TheKwas]

Tokyo.

[Anarius]

It's propably going to be really big, right?
After all, this isn't magic..

[boofhead]

I've heard of a similar concept with photo-receptors and photo-emitters all over a skin-tight body suit, in which light frequencies received on one side of the body are emitted out the other. It would be some kind of hairy-looking suit when not turned on. It would not give complete invisibility, as the nearer one looked towards the edges of a wearer's silhouette the more warped the image would become.

Would be great camoflague though for soldiers!

[jaklei]

Amazing. But scary now when i must get my hands on thermavision gogles to feel safe

[chris_uk_83]

All absolute bollocks. We haven't got invisibility devices yet. Most of the photos in that article are photoshopped, and the movies that "show" someone as invisible can be done with the right software on anyone's home PC.

I thought the bit about the "solid that goes transparent when you shine a laser on it" was funny. I've got plenty of material that you don't have to shine a laser on to make transparent, it's called perspex, glass, clingfilm etc. Just becasue something's transparent doesn't mean you can make an invisibility cloak out of it.

The author of the article even talks about 'blue screen' technology being an invisibility cloak! This is the same thing that is used in TV studios to display weather maps, or any background they choose! All it is is a TV trick, like everything in that article.

However, the final part about the negative refractive index material is real. Though as yet they've not managed to make anything larger than a pea completely invisible with it. Even then you have to encase it in a sphere of solid material, not making it very practical. Though it does work. This slightly more reliable article explains more for those who are interested.

[Niles Crane]

@ Chris

... Did you bother to read the article? They haven't said anything about having an 'invisibility cloak' yet. But that with their progress so far as you said, it could well be possible.

[chris_uk_83]

Are we looking at the same article here? The one I read makes frequent references to what it claims are existing technologies to render people or vehicles invisible.

The optical-camouflage technology, which has been developed by scientists at the University of Tokyo, has made the invisibility cloak a reality.

STS adaptive camouflage technology makes the object virtually invisible even from 20-25 feet away. It can prove deadly if applied to aircrafts completely camouflaging them from the enemy and wiping them out without a trace.

Hardly a few days back, Physicists figured out the complex mathematical equations for making objects invisible by bending light around them last year.

This one doesn't make sense, how can you figure something out a few days back last year? It goes on to say

The design makes use of tiny needles to be fitted into a hairbrush shaped cone at angles and lengths that would force light to pass around the cloak.

By exploiting the way that atoms move in solids the researchers at Imperial College London have made solid materials turn completely transparent.

This one has the video that says transparent materials make things invisible.

Back in 2003, a professor at the University of Tokyo created an optical camouflage system that makes anyone wearing a special reflective material seems to disappear.

though I'll let them off with that one because

A video camera records the real-life scenery behind the subject, transmits that image to a front-mounted projector, which then displays the scene on the reflective material.

This quote:

Scientists discovered a new way to make objects invisible back in 2006. the idea was to employ metamaterials, a complex hybrid structure of metal and insulator that makes light move around an object. But, it was not easy to make cloaking devices that work on more than one wavelength of light at a time. Check out this video simulation of an invisibility-equipped Aston Martin.

combines two completely unrelated things: metamaterials, and CGI special effect from a James Bond film. Metamaterials are real, invisible Aston Martins, sadly, are not.

As I said, I'll yield the negative refractive index and microwave metamaterial because there is research to support them. Though, as we agree, those are not yet capable of creating the famed invisibility cloak.

[Niles Crane]

What you have quoted (and I have read this same story in various other articles) is on a very small scale. Pea-sized scale. They have a very basic prototype of the technology, but they still haven't figured out how to enlarge their 'cloak' so as to render something like a human invisible.

[chris_uk_83]

That's what I've been trying to say! I know a bit about this research because I've met one of the guys involved with it, and listened to him talk on the research. He came to do a colloquium talk at my university not too long ago. Pretty interesting stuff in all.

[Simetrical]

I've heard of a similar concept with photo-receptors and photo-emitters all over a skin-tight body suit, in which light frequencies received on one side of the body are emitted out the other. It would be some kind of hairy-looking suit when not turned on. It would not give complete invisibility, as the nearer one looked towards the edges of a wearer's silhouette the more warped the image would become.

More than that, we don't have the technology to create such small, photorealistic, and highly directional light emitters, to my knowledge. You'd have to have an array pointing in different directions to become translucent from a wide range of angles. The metamaterial stuff looks more promising, although apparently it's not expected to be as much an invisibility cloak as an invisibility wall or truck: not something you can wear easily. And that's some way down the line, when a lot of practical issues are worked out.

This is still something the military will be dying for. Other than that, probably useless except as a novelty.

[LSJ]

When the world armies use such technologies, the soldier's helmet will simply adapt. We would use computers and cameras to see the "invisible" people. Its good for going against groups like the Taliban, but today's modern armies already have many ways to counter it.

[The Good]

Oh no, they already invented invisibility!

You know that these technologies shouldn't even reach public access, because criminals would use it to gain the advantage. Within a few years, if it does become public (buyable in stores), we will have a higher rate of crime.

[Simetrical]

When the world armies use such technologies, the soldier's helmet will simply adapt. We would use computers and cameras to see the "invisible" people. Its good for going against groups like the Taliban, but today's modern armies already have many ways to counter it.

Obviously, yes. But the big investments are being made in things to fight poorly-organized guerrilla groups, because that's who it looks like we'll be fighting for the foreseeable future.

You know that these technologies shouldn't even reach public access, because criminals would use it to gain the advantage. Within a few years, if it does become public (buyable in stores), we will have a higher rate of crime.

Nonsense. First of all, the bulk of the suit would require that it be an invisible truck or something, not a single person. Second of all, that couldn't practically be driven anywhere, because everyone would smash into you and damage the cloak or otherwise give away your position. Finally, it's not that hard to circumvent with fairly cheap specialized equipment. The vehicle would still turn up on police radar, to begin with (my understanding is it can only effectively shield you from one frequency at once).

Incidentally, something to note is that if light from the outside passes around you, you don't get to see it. Anyone who's perfectly invisible has to be blind as well. Again, this would be circumvented by using different frequencies.