The Naval Research Laboratory is studying undersea lasers for submarine communications.
Communicating with submarines while they operate beneath the seas has been one of the longstanding challenges for the military. Naval researchers say they have made headway on an innovative way to use undersea lasers that could be used to communicate with submarines.
The idea is to use lasers beams to create sound through mini-explosions. High intensity laser beams focus themselves when passing through materials like water. As the laser focuses, electrons are torn off water molecules. As they become superheated, they create a powerful “pop.”
The “pop,” according to naval scientists, is actually an explosion of steam creating a 220 dB sound pulse. The laser pulses could originate from either a submarine under the water or an aircraft above.
During the Cold War, communicating with submerged submarines was critical in case of a nuclear exchange. Radio waves do not propagate well through sea water, so scientists looked to other methods, like very low frequency and extremely low frequency radio waves. The idea is to pass on messages to submarines, without the need for them to surface (and thus potentially giving away their location).
Although this requirement is not as critical as it once was, the U.S. Navy clearly remains interested in the underwater communications challenge.