After the patches able to measure the fever, the temperature of everything we touch, analyze the chemicals and our breathing, the "smart patches" are coming, which will retire the very common earphones.
The journal "Science Advances" presented patches, made with transparent and flexible nanomembranes in the laboratories of the National Institute of Science and Technology in Ulsan, South Korea, able to reproduce and record sounds and voices.
In the not too distant future, they could become disabled aids, but also wearable technologies for speech recognition in unlocking devices such as smartphones and computers.
The membranes that make the skin hi-tech are thinner than a temporary tattoo: they contain a tiny network of silver threads, coated with layers of polymers, which are flexible, transparent and capable of conducting acoustic signals. In the case of the loudspeaker "patch", the electrical audio signal coming from the music player causes the reticle to heat up to 33 degrees: the pressure variations in the surrounding air are perceived by our ears as sound waves.
The microphone 'patch', on the other hand, works in the opposite way: it converts the sound waves produced by the voice into electrical signals, which are conveyed to the smartphone or computer to be stored and possibly reproduced. The patch is able to record the sounds emitted by the mouth, but not only: if applied to the throat, it can also recognize words by the movement of the vocal cords perceived through the skin.
The researchers tested it on four volunteers as a voice recognition device for unlocking the smartphone and in 98% of cases the system identified the owner's voice.
Koreans' next goal is to improve their accuracy in distinguishing voices and recognizing words. The speaker patch could also be perfected by increasing the volume and improving the sound quality, which is a bit tinny at the moment. In view of a possible arrival on the market, it will also be necessary to find alternative and less expensive materials for production.