Frickin 'Laser Beams
Scientists have discovered how to use a laser to transmit audio signals from music to speech to a person throughout the room without a receiver – a potential breakthrough for the future of audio and communications
" Our system can be used from a distance to direct information directly to someone else's ear, "said Charles M. Wynn, a Massachusetts Institute of Technology study in a press release. "It's the first system that uses lasers that are completely safe for the eyes and skin to locate an audible signal for a specific person in any environment."
In an article published in the journal on Friday Optics Letters the MIT team describes how it has developed two different methods of transmitting sound, music and voice over a laser.
Both techniques use the so-called photoacoustic effect, the so-called photoacoustic effect sound waves as a result of a light-absorbing material. At MIT research, this material was water vapor in the air.
For one of their methods, the researchers "swept" a laser beam at the speed of sound and changed the length of the sweeps to encode various audible signals pitches.
This technique allowed them to transmit a person over 8 meters away, at a volume of 60 decibels ̵
For the other method, they encoded an audio message by adjusting the power of a laser beam. They said that technique had produced a calmer, but clearer result.
As cool as it would be to use a laser to sneak a message through a crowded room for a friend, the MIT team has far more important applications in mind for their technology.
They believe that further research will allow them to increase the transmission distance, which could make the technique useful in dangerous situations, such as: B. during a mass shooting. The authorities could forward instructions directly to individuals without anyone hearing them.
"We hope that eventually a commercial technology will develop," said researcher Ryan M. Sullenberger. "There are many exciting opportunities, and we want to develop communication technology in a useful way."
READ MORE: New technology uses lasers to send audible messages to specific persons [The Optical Society]
More about lasers: Russia's newest weapon: a laser cannon