If you are a fan of Crime movies and TV shows, then you surely have seen the glasses Police has in their interrogation rooms, where officers are in another room and can see the interrogation room through it, but anyone sitting in the interrogation room cannot see them. That glass is a one-way glass, and has been around for quite sometime.
Another interesting example of the one-way glass is found with this public toilet:
Until recently there was no development of a similar technology for sound, but a new device was created by a team of researchers in the Department of Electrical and Computer Engineering at The University of Texas at Austin that allows for "one-way sound".
Researchers created a cavity loaded with tiny CPU (central processing unit) fans that spin the air with a specific velocity. When the sound waves reach the cavity, they follow a specific route to one of the three pipes, which have a microphone at the end. Given that air is being circulated in a specific direction, this prevents backwards transmission, therefore resulting in uni-directional sound.
The results have been published on Science Magazine, in a paper titled Sound Isolation and Giant Linear Nonreciprocity in a Compact Acoustic Circulator. Even though this research is still on a preliminary stage, in the future it could lead to the creation of the acoustical version of the one-way glass.
Also, the results obtained in this study might be useful to produce new and revolutionary sound insulators, which would be beneficial for the sound industry and, in fact, it is expected that this industry will have a keen interest on this research.
What do you think about this new technology? Let us know in the comments