In the Crysis games, you play a super Soldier in a suit who can turn invisible and toss aliens like Hacky Sacks. Outside of video games, scientists at the Dallas NanoTech Institute used sheets of carbon nano tubes, which are one-atom thick sheets of carbon rolled up into microscopic tubes, to bend light around the sheets, effectively cloaking them.
The key to the technique they used is the same effect that causes dying travelers in the desert to think an empty patch of land is an oasis, the mirage effect. The temperature difference between sand and air bend light rays, directing the light rays towards the hapless traveler’s eyes instead of bouncing them off the surface. This makes a “puddle of sky” on the ground, which any desperate dying traveler would think is water.
The carbon nano tube sheets were immersed in water and heated up, which also heated up the water, which caused light to bend away from the sheet , and obscuring whatever was behind the sheet. It’s impractical as a military cloaking device as you would have to wear a super-hot suit that has to be immersed in water, but it’s certainly cool as hell.
Hats off to scientists at the University of Rochester in New York, who have managed to produce a cheap ‘invisibility cloak’ effect using readily available materials and a lot of clever thinking. Through a combination of optical lenses, any object that passes behind a certain line of sight can be made to disappear from view.
‘The Rochester Cloak’, as it’s being dubbed, uses a simplified four-lens system that essentially bends light around any objects you put into the middle of the chain — you’re able to see the area in the background as normal, but not the item in the foreground. According to its inventors, it can be scaled up using any size of lens, and the team responsible for the setup has used standard, off-the-shelf hardware
“People have been fascinated with cloaking for a very long time,” said John Howell, a Professor of Physics at the University. “It’s recently been a really popular thing in science fiction and Harry Potter… I think people are really excited about the prospect of just being invisible.”
“From what we know this is the first cloaking device that provides three-dimensional, continuously multidirectional cloaking,” said doctoral student Joseph Choi, one of the team who worked on the project, when speaking to Reuters. “I imagine this could be used to cloak a trailer on the back of a semi-truck so the driver can see directly behind him. It can be used for surgery, in the military, in interior design, art.”
What makes this system so interesting is that it’s simple, inexpensive and capable of working at multiple angles, as long as the object remains inside the series of lenses. Howell and Choi say it cost them $1,000 to get all of the necessary equipment together, but it can be done more cheaply. A patent is pending for their invention but the pair have put together instructions on making your own Rochester Cloak at home for less than $100.
Scientists are getting closer to creating a real-life invisibility cloak.
A new study published in the journal Science shows scientists have created what they are calling a “ultrathin invisibility skin cloak for visible light.” The cloak has been shown to cover an object and—by manipulating certain wavelengths of light—render it invisible.
Light plays a central role in how we see objects. According to the Los Angeles Times, usually light bounces off of things and becomes distorted, which helps a person see the angles and curves of an object. However, the LA Times writes that the cloak is covered with “nanoantennas made of tiny gold blocks of different sizes that can counteract that distortion, making it seem to an observer like the light is coming from a flat surface.”
The cloak is 80 nanometers thick, which is a bonus since the study authors say prior attempts have been too bulky and therefore difficult to scale up. Still, the current cloak only covers a very tiny object, so there’s a long way to go before people can make themselves invisible or hard to see.
Other research teams are also looking into the creation of an invisibility cloak. In early July, University of California, San Diego researchers designed their own early version. “Invisibility may seem like magic at first, but its underlying concepts are familiar to everyone. All it requires is a clever manipulation of our perception,” Boubacar Kanté, a professor in the Department of Electrical and Computer Engineering at the UC San Diego Jacobs School of Engineering said in a statement about his work. “Full invisibility still seems beyond reach today, but it might become a reality in the near future thanks to recent progress in cloaking devices.
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