Acoustic cloaking device echoes advances in optical cloaking

August 15, 2011

Optical cloaking devices that enable light to gracefully slip around a solid object were once strictly in the realm of science fiction. Today they have emerged as an exciting area of study, at least on microscopic scales.

A new twist on this intriguing technology can now be "seen" in the field of acoustics. A team of researchers from the Universitat Politecnica de Valencia and the Universidad de Valencia have created a prototype of an acoustic cloak by using a 2-D .

Unlike sound-canceling technologies that eliminate noise by creating the exact-but-opposite waveform, an acoustic cloak would enable to travel around an object without changing their shape or direction.

The proposed sound cloak, as described in the AIP's journal Applied Physics Letters, would consist of 120 cylinders, each 15 millimeters in diameter.

By carefully arranging them around an object 22.5 centimeters across, the researchers experimentally demonstrated that sound waves of a specific frequency (3061 Hertz, with about a 100-Hertz bandwidth) maintain their original wave-front pattern as they pass around and beyond the object.

According to the researchers, the narrow operating band of the cloak can be overcome by increasing the number of cylinders used to create the cloak.

If such a technique could be applied in real-world designs, it could enable better soundscapes in urban environments, better acoustics in performance halls, and quieter helmets that protect the ears from extreme noises, the researchers speculate.

"Acoustic cloak for airborne sound by inverse design" is published in .

Explore further: Next generation cloaking device demonstrated

Related Stories

Next generation cloaking device demonstrated

January 15, 2009

A device that can bestow invisibility to an object by "cloaking" it from visual light is closer to reality. After being the first to demonstrate the feasibility of such a device by constructing a prototype in 2006, a team ...

New invisibility cloak hides objects from human view

July 27, 2011

For the first time, scientists have devised an invisibility cloak material that hides objects from detection using light that is visible to humans. The new device is a leap forward in cloaking materials, according to a report ...

Recommended for you

CP violation or new physics?

July 25, 2016

(Phys.org)—Over the past few years, multiple neutrino experiments have detected hints for leptonic charge parity (CP) violation—a finding that could help explain why the universe is made of matter and not antimatter. ...

Knots in chaotic waves

July 29, 2016

New research, using computer models of wave chaos, has shown that three-dimensional tangled vortex filaments can in fact be knotted in many highly complex ways.

Realizing quantum bits

July 26, 2016

In computers of the future, information might be stored in the form of quantum bits. But how can a quantum bit be realised?

1 comment

Adjust slider to filter visible comments by rank

Display comments: newest first

hush1
not rated yet Aug 18, 2011
Kewl
Undisturbed sleeping under a bridge with just the right number of blankets,...I mean,... cloaks of cylinders.

Actually, great news for 'new' acoustic anechoic chambers.
Orchestra's members cloaked, without hearing each other.
No more practice "sound proof" rooms.

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.