Researchers have created a new disc-shaped plastic invisibility cloak, using a standard 3D printer, that deflects microwave beams to make objects disappear.
Producing a cloak in this fashion is inexpensive and easy, said researcher Yaroslav Urzhumov from Duke University.
In 2006, Duke engineers demonstrated the first working invisibility cloak in complex laboratory experiments.
Now it appears creating a simple cloak has become a lot simpler.
The newer version deflects microwave beams, but researchers feel confident that in the not-so-distant future, the cloak can work for higher wavelengths, including visible light.
"We believe this approach is a way towards optical cloaking, including visible and infrared," said Urzhumov, assistant research professor in electrical and computer engineering at Duke's Pratt School of Engineering.
"And nanotechnology is available to make these cloaks from transparent polymers or glass. The properties of transparent polymers and glasses are not that different from what we have in our polymer at microwave frequencies," Urzhumov said.
"I would argue that essentially anyone who can spend a couple thousand dollars on a non-industry grade 3-D printer can literally make a plastic cloak overnight," said Urzhumov.
The disc-like cloak has an open area in its center where the researchers placed an opaque object. When microwave beams were aimed at the object through the side of the disk, the cloak made it appear that the object was not there.
"The design of the cloak eliminates the 'shadow' that would be cast, and suppresses the scattering from the object that would be expected," said Urzhumov.
"In effect, the bright, highly reflective object, like a metal cylinder, is made invisible. The microwaves are carefully guided by a thin dielectric shell and then re-radiated back into free space on the shadow side of the cloak," he said.
Urzhumov said that theoretically, the technique can be used to create much larger devices.
"Computer simulations make me believe that it is possible to create a similar polymer-based cloaking layer as thin as one inch wrapped around a massive object several meters in diameter," he said.
"I have run some simulations that seem to confirm this point," said Urzhumov.
The study was published in the journal Optics Letters.
