Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

New Metamaterials Device Focuses Sound Waves Like a Camera Lens

08.08.2012
In a cover article in The Journal of Applied Physics, a team of Penn State researchers has designed and computationally tested a type of manmade metamaterial capable for the first time of manipulating a variety of acoustic waves with one simple device.

This invention will benefit almost all current sonic and ultrasonic applications, such as ultrasonic nondestructive evaluations and ultrasonic imaging. The device should also provide more accurate and efficient high-intensity focused ultrasound(HIFU) therapies, a non-invasive heat-based technique targeted at a variety of cancers and neurological disorders.


Sz-Chin Steven Lin, Penn State

The acoustic beam aperture modifier can effectively shrink or expand the aperture of an acoustic beam with minimum energy loss and waveform distortion. With such an acoustic lens, the need for a series of expensive transducers of different sizes is eliminated.

Optical metamaterials have been widely studied in the past decade for applications such as cloaking and perfect lenses. The basic principles of optical metamaterials apply to acoustic metamaterials. Artificial structures are created in patterns that bend the acoustic wave onto a single point, and then refocus the acoustic wave into a wider or narrower beam, depending on the direction of travel through the proposed acoustic beam aperture modifier. The acoustic beam aperture modifier is built upon gradient-index phononic crystals, in this case an array of steel pins embedded in epoxy in a particular pattern. The obstacles (steel pins) slow down the acoustic wave speed in order to bend the acoustic waves into curved rays.

According to post-doctoral scholar and the paper’s lead author, Sz-Chin Steven Lin, while other types of acoustic metamaterials also could focus and defocus an acoustic beam to achieve beam aperture modification (although prior to this work no such beam modifier has been proposed), their device possesses the advantage of small size and high energy conservation. Currently, researchers and surgeons need to have many transducers of different sizes to produce acoustic waves with different apertures. This is analogous to having to swap out lenses on a camera to change the lens’s aperture. With this invention, by changing the modifier attached to the transducer the desired aperture can be easily attained.

“Design of acoustic beam aperture modifier using gradient-index phononic crystals,” by Lin, Bernhard Tittmann, and Tony Jun Huang, is the first design concept for an acoustic beam aperture modifier to appear in the scientific literature, and no acoustic beam modifier device is available in the market. As a result, the authors expect their device could have wide applications across several important acoustic fields, from medical ultrasound to higher sensitivity surface acoustic wave sensors to higher Q factor resonators. The team is currently making a prototype based on this design.

Support for their research came from the National Science Foundation, the National Institutes of Health (NIH) Director’s New Innovator Award, and the Penn State Center for Nanoscale Science (MRSEC). Sz-Chin Steven Lin is a post-doctoral scholar in the Penn State Department of Engineering Science and Mechanics: ssl130@psu.edu. Bernhard Tittmann is Schell professor and professor of engineering science and mechanics: brt4@psu.edu. Tony Jun Huang is associate professor of engineering science and mechanics: juh17@psu.edu.

The Materials Research Institute is Penn State’s home for interdisciplinary materials research, supporting over 220 engineers and scientists and 800-plus graduate students, post-docs and visiting scientists. Visit MRI at www.mri.psu.edu for other recent materials discoveries at Penn State.

| Newswise Science News
Further information:
http://www.mri.psu.edu
http://www.psu.edu

More articles from Materials Sciences:

nachricht Glass's off-kilter harmonies
18.01.2017 | University of Texas at Austin, Texas Advanced Computing Center

nachricht Explaining how 2-D materials break at the atomic level
18.01.2017 | Institute for Basic Science

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: How gut bacteria can make us ill

HZI researchers decipher infection mechanisms of Yersinia and immune responses of the host

Yersiniae cause severe intestinal infections. Studies using Yersinia pseudotuberculosis as a model organism aim to elucidate the infection mechanisms of these...

Im Focus: Interfacial Superconductivity: Magnetic and superconducting order revealed simultaneously

Researchers from the University of Hamburg in Germany, in collaboration with colleagues from the University of Aarhus in Denmark, have synthesized a new superconducting material by growing a few layers of an antiferromagnetic transition-metal chalcogenide on a bismuth-based topological insulator, both being non-superconducting materials.

While superconductivity and magnetism are generally believed to be mutually exclusive, surprisingly, in this new material, superconducting correlations...

Im Focus: Studying fundamental particles in materials

Laser-driving of semimetals allows creating novel quasiparticle states within condensed matter systems and switching between different states on ultrafast time scales

Studying properties of fundamental particles in condensed matter systems is a promising approach to quantum field theory. Quasiparticles offer the opportunity...

Im Focus: Designing Architecture with Solar Building Envelopes

Among the general public, solar thermal energy is currently associated with dark blue, rectangular collectors on building roofs. Technologies are needed for aesthetically high quality architecture which offer the architect more room for manoeuvre when it comes to low- and plus-energy buildings. With the “ArKol” project, researchers at Fraunhofer ISE together with partners are currently developing two façade collectors for solar thermal energy generation, which permit a high degree of design flexibility: a strip collector for opaque façade sections and a solar thermal blind for transparent sections. The current state of the two developments will be presented at the BAU 2017 trade fair.

As part of the “ArKol – development of architecturally highly integrated façade collectors with heat pipes” project, Fraunhofer ISE together with its partners...

Im Focus: How to inflate a hardened concrete shell with a weight of 80 t

At TU Wien, an alternative for resource intensive formwork for the construction of concrete domes was developed. It is now used in a test dome for the Austrian Federal Railways Infrastructure (ÖBB Infrastruktur).

Concrete shells are efficient structures, but not very resource efficient. The formwork for the construction of concrete domes alone requires a high amount of...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

12V, 48V, high-voltage – trends in E/E automotive architecture

10.01.2017 | Event News

2nd Conference on Non-Textual Information on 10 and 11 May 2017 in Hannover

09.01.2017 | Event News

Nothing will happen without batteries making it happen!

05.01.2017 | Event News

 
Latest News

A big nano boost for solar cells

18.01.2017 | Power and Electrical Engineering

Glass's off-kilter harmonies

18.01.2017 | Materials Sciences

Toward a 'smart' patch that automatically delivers insulin when needed

18.01.2017 | Life Sciences

VideoLinks
B2B-VideoLinks
More VideoLinks >>>