A team of scientists has studied a way to listen to any sound without headphones, thanks to the ultrasonic bundles that promise to eliminate devices to wear.
Imagine listening to your favorite headphones without headphones, with the sound that seems to materialize in the air, ascolating it only you and no one else around. It seems science fiction, but it is not: a team of researchers from Pennsylvania State University, in fact, has developed a technology that creates “sound enclaves”, that is limited areas in which ultrasonic bundles cross, producing sounds audible only in specific points of space.
This innovation was on Proceedings of the National Academy of Sciences USA and promises to revolutionize the audio experienceeliminating the need to wear uncomfortable or bulky devices and offering an invisible alternative to traditional solutions.
Waves that bend. This futuristic technology is based on the calibrated functioning of two ultrasonic bundles, normally imperceptible to the human ear, which are bent around the obstacles present in the air until they meet at a precise point. Only at that point will the audible sound be reproduced, and to replace current devices, It must be directed as precisely possible to our ear pavilions.
The ultrasounds operate at frequencies over 20 Kilohertz, the maximum threshold of human hearing, and are already used in the medical field. The real news introduced by Professor Yun Jing’s team, acoustic expert, was combine ultrasonic bundles with 3D printed materials capable of modeling sound wavesallowing them to join the intersection and thus generate the sound enclaves, without the need for traditional headphones or speakers.
Successful test. To demonstrate the functioning of their invention, the researchers have positioned Two ultrasound emittersjust over fifteen centimeters wide and covered with special metamaterials, and made them converge behind the head of a mannequin. When a beam bent on the right crossed with one bent on the left, the ultrasonic waves interfere with each other, leaving one behind them audible sound trace of 500 hertz.
As tests, the researchers transmitted the famous choir Hallelujah taken from Messiah by Friedrich Händel, creating an invisible and perfectly localized listening area. Although the audio quality can still be improved, The pressure rate generated by the waves was well below the safety limits established by the FDA (there Food and Drug Administration US), making the technology promising for future use.
Wireless future. The potential applications of this brilliant intuition are numerous: from domestic entertainment, where Each viewer could enjoy his audio without disturbing others, up to cars, creating separate listening areas for driver and passengers.
Jing plans to refine technology with machine learning algorithms to improve their sound quality and expand their possibilities of use.
Although the road towards a large -scale diffusion is still long, such an innovation opens the doors to a future in which the sound will be perceived almost by magicfreeing our ears from essential objects and accessories, but already ready to be labeled as vintage by the new generations.
