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 Researchers devise microreactor to study formation of methane hydrate
23.08.2017 | NYU Tandon School of Engineering

nachricht Meter-sized single-crystal graphene growth becomes possible
22.08.2017 | Science China Press

All articles from Materials Sciences >>>

The most recent press releases about innovation >>>

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

Im Focus: Fizzy soda water could be key to clean manufacture of flat wonder material: Graphene

Whether you call it effervescent, fizzy, or sparkling, carbonated water is making a comeback as a beverage. Aside from quenching thirst, researchers at the University of Illinois at Urbana-Champaign have discovered a new use for these "bubbly" concoctions that will have major impact on the manufacturer of the world's thinnest, flattest, and one most useful materials -- graphene.

As graphene's popularity grows as an advanced "wonder" material, the speed and quality at which it can be manufactured will be paramount. With that in mind,...

Im Focus: Exotic quantum states made from light: Physicists create optical “wells” for a super-photon

Physicists at the University of Bonn have managed to create optical hollows and more complex patterns into which the light of a Bose-Einstein condensate flows. The creation of such highly low-loss structures for light is a prerequisite for complex light circuits, such as for quantum information processing for a new generation of computers. The researchers are now presenting their results in the journal Nature Photonics.

Light particles (photons) occur as tiny, indivisible portions. Many thousands of these light portions can be merged to form a single super-photon if they are...

Im Focus: Circular RNA linked to brain function

For the first time, scientists have shown that circular RNA is linked to brain function. When a RNA molecule called Cdr1as was deleted from the genome of mice, the animals had problems filtering out unnecessary information – like patients suffering from neuropsychiatric disorders.

While hundreds of circular RNAs (circRNAs) are abundant in mammalian brains, one big question has remained unanswered: What are they actually good for? In the...

Im Focus: RAVAN CubeSat measures Earth's outgoing energy

An experimental small satellite has successfully collected and delivered data on a key measurement for predicting changes in Earth's climate.

The Radiometer Assessment using Vertically Aligned Nanotubes (RAVAN) CubeSat was launched into low-Earth orbit on Nov. 11, 2016, in order to test new...

Im Focus: Scientists shine new light on the “other high temperature superconductor”

A study led by scientists of the Max Planck Institute for the Structure and Dynamics of Matter (MPSD) at the Center for Free-Electron Laser Science in Hamburg presents evidence of the coexistence of superconductivity and “charge-density-waves” in compounds of the poorly-studied family of bismuthates. This observation opens up new perspectives for a deeper understanding of the phenomenon of high-temperature superconductivity, a topic which is at the core of condensed matter research since more than 30 years. The paper by Nicoletti et al has been published in the PNAS.

Since the beginning of the 20th century, superconductivity had been observed in some metals at temperatures only a few degrees above the absolute zero (minus...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

Event News

Call for Papers – ICNFT 2018, 5th International Conference on New Forming Technology

16.08.2017 | Event News

Sustainability is the business model of tomorrow

04.08.2017 | Event News

Clash of Realities 2017: Registration now open. International Conference at TH Köln

26.07.2017 | Event News

 
Latest News

What the world's tiniest 'monster truck' reveals

23.08.2017 | Life Sciences

Treating arthritis with algae

23.08.2017 | Life Sciences

Witnessing turbulent motion in the atmosphere of a distant star

23.08.2017 | Physics and Astronomy

VideoLinks
B2B-VideoLinks
More VideoLinks >>>