Duke University engineers have developed a novel sensor that is more efficient, versatile and cheaper for potential use in such applications as airport security scanners and collision avoidance systems for aircraft, cars or maritime vessels.
The researchers fabricated a unique material, known as a metamaterial, that acts as a lens to image scenes using fewer components than conventional detectors. Because of the properties of this man-made material, much of the additional equipment needed for conventional detector systems – like lenses, mechanical positioners and data storage or transmissions devices – are not required.
The material itself is a thin laminate with row-upon-row of tiny squares etched onto copper, each one of which is tuned to a different frequency of light. The material is flexible and durable enough to be attached to a wall, wrapped around corners or even laid on the floor like a rug, making it an inexpensive alternative for a variety of sensing applications.
The new system works with microwave light and produces two-dimensional images. The researchers are currently exploring moving the technology to three-dimensional capability in real-world settings.
The Duke researchers reported their findings Jan. 18 on-line in the journal Science. The research was supported by the Air Force Office of Scientific Research.
"By taking advantage of the unique properties of these metamaterials, we were able to create a system capable of microwave imaging without lenses or any moving parts, " said John Hunt, a graduate student working in the laboratory of senior investigator David R. Smith, William Bevan Professor of electrical and computer engineering at Duke's Pratt School of Engineering.
As an example, Hunt said that in many security situations, imaging systems move a single sensor device with a small aperture in front of the body of the subject, creating an effectively larger aperture. The scanning waves travel through clothing, but skin or other objects reflect the waves. The new device can scan the entire field at once, which would allow for faster and more efficient screening, the researchers said.
"Using conventional systems such as airport security cameras or collision-detection devices, you have to wait for a scan to complete before you can see an image, while the new system can scan an entire range at once," Hunt said.
The metamaterial is made of thousands of tiny apertures that can detect a wide spectrum of frequencies, allowing it to obtain a more global image of the scene, the researchers said.
"Each individual element of the metamaterial is tuned to narrow frequency," said Tom Driscoll, a post-doctoral fellow from the University of California – San Diego currently working in the Smith lab. "Together the individual elements scan the entire range to capture information about a scene very quickly."
"This system allows us to collect and compress the image during collection, instead of later, averting the detector, storage and transmission costs associated with conventional imaging of a scene," Driscoll said.
Duke University: http://www.duke.edu
This press release was posted to serve as a topic for discussion. Please comment below. We try our best to only post press releases that are associated with peer reviewed scientific literature. Critical discussions of the research are appreciated. If you need help finding a link to the original article, please contact us on twitter or via e-mail.
Self-driving 'taxibots' could cut number of cars in cities by 90 percent, study suggests
While your key fob may be safely in your house, your locked car could actually be wide open for tech-savvy crooks. Vladimir Duthiers reports on how high-tech car thieves are exploiting security gaps.
A radar-like system that fits inside a Wi-Fi box can record health data and keep tabs on your mood – without you even noticing
Amanda Stowers is beating up on her drone as her professor watches on with glee. It may seem cruel but it's all in the name of science. No matter how hard or how many times Amanda hits the drones' wing, it always recovers and keeps on flapping.
IBM is partnering with Apple and medical device companies to develop a cloud-based health platform for its Watson supercomputer
Commercial airlines could be vulnerable to hacking via inflight Wi-Fi. CBSN's Vladimir Duthiers and Elaine Quijano have the details.
The takedown of the Beebone botnet is the first major victory for a multinational cybercrime-fighting group
Fully autonomous weapons should be banned by international treaty, says a report by Human Rights Watch and Harvard Law School
We have the technology to dramatically increase the independence of people with spinal-cord injuries. The problem is bringing it to market and keeping it there.
The US president has declared a national state of emergency over cybercrime, but his plan is unenforceable at best, and could even do real harm