Trick to talk through walls

The two neighbors, separated by a wall, can now talk normally through a simple sound transmission trick created by Japanese and Korean scientists , without the need for support of devices. High technology like phones.

A team of Japanese and Korean research experts have come up with a way to help turn a tough wall transparent and no longer a barrier to sound. The process is based on drilling small holes on a solid solid material, such as a wall, and covering one side of it with a film made of thin plastic film coated with food easily found in any kitchen. .

"The wall with bare holes will greatly interfere with the sound transmission. However, when attaching the membrane to the wall, good sound transmission is virtually barrier-free," the research report posted. Download in Physical Review Letters.

Picture 1 of Trick to talk through walls
The new procedure will help you not to struggle with your neighbor, a wall away from you.(Photo: Shutterstock)

Physicists tried to transmit sound through solid walls by drilling holes, but failed because the intact parts of the wall reflected most of those sounds.

Specialist Oliver Wright, a member of the research team from Hokkaido University (Japan), emphasized that the only way to direct a large amount of sound through holes in the wall is to ensure sound waves move through the hole. much faster than they were about to approach and the time they passed the hole.

Mr. Wright's group decided to use food wrap to cover every hole in the wall, creating an effective resonance. Their method is similar to that used to create a physical effect called "extraordinary optical transmission" discovered by Thomas Ebbesen of the University of Strasbourg (France) in 1998.

In experiments, the new system can transmit between 76% and nearly 97% of the size of the original sound source, depending on the size of the holes corresponding to the total area of ​​the wall.

Johan Christensen, a photonic engineer at the Danish Technical University, commented: "The results are truly amazing. The most remarkable thing is that they (Japanese and Korean researchers) have witnessed I have the ability to squeeze a large amount of sound through tiny tiny gaps ".

The team envisioned two main types of applications from their findings."By using a wall with holes of different sizes, one can create an effective security barrier for oral communication in places like banks or on taxis. Also, when squeezing large amounts of energy through a single hole, we can create a sound microscope, applied to devices that help detect early stage tumors in the body, which are so small that conventional ultrasound techniques cannot be detected , " Wright said.