Working in partnership with the Indian Institute of Technology in Kanpur, they tested the numerical properties of a flat lens made out of ‘meta-material’ - a material that gains its properties from its structure rather than its composition. This material is thought to defy the laws of physics, allowing objects to appear exactly as they are rather than upside down as seen in a normal convex or concave lens.
Dr Sebastien Guenneau, from Liverpool’s Department of Mathematical Sciences, explains: “We know that light can be controlled using ‘meta-material’ which can bend electromagnetic radiation around an area of space, making any object within it appear invisible. Now we have produced a mathematical model that proves this theory also works for sound.
“This theory becomes particularly interesting when considering ultrasound, which is a sound pressure used to penetrate an object to help produce an image of what the object looks like inside. This is most commonly used in pregnancy scans to produce an image of a foetus. We found that at a particular wave frequency the meta-material has a negative refraction effect, which means that the image produced in the flat lens appears at a high resolution in exactly the same way it appears in reality.
“What surprised us most of all, however, was at the point where negative refraction occurs the meta-material becomes invisible, suggesting that if we were to use this in sonogram technology, it could be possible to make the image appear in mid-air like a hologram rather than on a computer screen. We also found that if we arranged the meta-material in a checkerboard fashion, sound became trapped, making noisy machines, for example, quieter.”
The scientists predict that the technology could be adapted for tests at higher sound frequencies such as when drilling for oil, where a more accurate image of the earth could be made in order to pin point where drilling should take place.
Samantha Martin | alfa
New way to write magnetic info could pave the way for hardware neural networks
21.11.2017 | Imperial College London
From Hannover around the world and to the Mars: LZH delivers laser for ExoMars 2020
21.11.2017 | Laser Zentrum Hannover e.V.
The WHO reports an estimated 429,000 malaria deaths each year. The disease mostly affects tropical and subtropical regions and in particular the African continent. The Fraunhofer Institute for Silicate Research ISC teamed up with the Fraunhofer Institute for Molecular Biology and Applied Ecology IME and the Institute of Tropical Medicine at the University of Tübingen for a new test method to detect malaria parasites in blood. The idea of the research project “NanoFRET” is to develop a highly sensitive and reliable rapid diagnostic test so that patient treatment can begin as early as possible.
Malaria is caused by parasites transmitted by mosquito bite. The most dangerous form of malaria is malaria tropica. Left untreated, it is fatal in most cases....
The formation of stars in distant galaxies is still largely unexplored. For the first time, astron-omers at the University of Geneva have now been able to closely observe a star system six billion light-years away. In doing so, they are confirming earlier simulations made by the University of Zurich. One special effect is made possible by the multiple reflections of images that run through the cosmos like a snake.
Today, astronomers have a pretty accurate idea of how stars were formed in the recent cosmic past. But do these laws also apply to older galaxies? For around a...
Just because someone is smart and well-motivated doesn't mean he or she can learn the visual skills needed to excel at tasks like matching fingerprints, interpreting medical X-rays, keeping track of aircraft on radar displays or forensic face matching.
That is the implication of a new study which shows for the first time that there is a broad range of differences in people's visual ability and that these...
Computer Tomography (CT) is a standard procedure in hospitals, but so far, the technology has not been suitable for imaging extremely small objects. In PNAS, a team from the Technical University of Munich (TUM) describes a Nano-CT device that creates three-dimensional x-ray images at resolutions up to 100 nanometers. The first test application: Together with colleagues from the University of Kassel and Helmholtz-Zentrum Geesthacht the researchers analyzed the locomotory system of a velvet worm.
During a CT analysis, the object under investigation is x-rayed and a detector measures the respective amount of radiation absorbed from various angles....
The quantum world is fragile; error correction codes are needed to protect the information stored in a quantum object from the deteriorating effects of noise. Quantum physicists in Innsbruck have developed a protocol to pass quantum information between differently encoded building blocks of a future quantum computer, such as processors and memories. Scientists may use this protocol in the future to build a data bus for quantum computers. The researchers have published their work in the journal Nature Communications.
Future quantum computers will be able to solve problems where conventional computers fail today. We are still far away from any large-scale implementation,...
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21.11.2017 | Physics and Astronomy
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21.11.2017 | Health and Medicine