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Navy Scientists Develop Laser For Underwater Communication
Researchers at the Naval Research Laboratory claim to have come up with a better tool for underwater acoustics. The new system uses laser light to create sound underwater from a distance. This technology could allow planes a much easier method of communicating with submarines without the need for a floating buoy. "Efficient conversion of light into sound can be achieved by concentrating the light sufficiently to ionize a small amount of water, which then absorbs laser energy and superheats. The result is a small explosion of steam, which can generate a 220 decibel pulse of sound. Optical properties of water can be manipulated with very intense laser light to act like a focusing lens, allowing nonlinear self-focusing (NSF) to take place. In addition, the slightly different colors of the laser, which travel at different speeds in water due to group velocity dispersion (GVD), can be arranged so that the pulse also compresses in time as it travels through water, further concentrating the light. By using a combination of GVD and NSF, controlled underwater compression of optical pulses can be attained."
...but do they have plans to attach them to sharks?
I knew it! Sharks With Frickin' Lasers!
So what's to prevent someone's hydrophones from picking this up and realizing that there's a submarine within audible range of the communication?
#fuckbeta #iamslashdot #dicemustdie
To Swimmers and wildlife, when a plane is shooting this giant high-powered laser into the water, to communicate with the submarine?
achieved by concentrating the light sufficiently to ionize a small amount of water, which then absorbs laser energy and superheats. The result is a small explosion of steam, which can generate a 220 decibel pulse of sound.
Sorry, sharks have already beat the Navy to this.
It's like an acid trip man. I can like hear the pretty colors. Oh look, I see noise. Dude, this is soooo cool. Want some?
Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
I don't know how the audio volume of this system compares with sonar systems (though the article's 220db and 160db from http://www.oceanmammalinst.org/mgpaper.html kind of gives clues and weakly suggest might be as much as 64x), but I suspect the people who oppose the use of sonar by the navy on the theory that it hurts whales are going to go nuts over this one.
There is no where near enough info to actually assess any kind of threat, but I'm sure the panic button will be hit anyway.
How does this NOT pose a danger To Swimmers and wildlife
Because the Navy's Selachimorpha already ate them all then moved away to a safe distance, that's how.
Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
I wonder how many marine animals we'll cause to go deaf from this, which would probably end any chance of survival for those affected. http://www.makeitlouder.com/Decibel%20Level%20Chart.txt 220 decibels is incredibly loud in the air, I can only guess the extended intensity it travel with underwater...
You mean, like, dolphins have been doing for eons ?
So sharks with laser it is. Poll shouldn't be asking questions that can be answered so decisively.
will this kill flipper?
they should call it NSFW (Not Safe For Whales)
What, you can do that now? Why didn't anybody TELL me this??!
So now submarines can communicate with sharks with frickin' laser beams on their heads!?
If so, then you gotta watch out for SITM (Shark In The Middle)-attacks.
Sharks!
Subsurface Hydro-Acoustic Radiation Communication System (SHARCS)
That's my first and only thought, really.
They should call it Subsurface Hydro-Acoustic Radiation Communication System with Lasers (SHARCS with Lasers)
Cool! Amazing Toys.
Communication my arse! how long before this is turned into a weapon. Or is "communication" some secret word for "Killing" that I havent been told about?
"Tha' 'll communicate 'em cap'n'"
Seriously, why does the west continue to announce such things? We are currently in a cold war in the same way that USSR was with the west in 1948 (USSR was prepping for it will pretending to be friends to the west). China keeps EVERYTHING close to the vest and out and out lies or simply denies everything else. The west continues to fill in China (and the new future axis that will join them such as North Korea, Iran, Venezuela, etc) on how we do things. This gives them plenty of time to develop means of listening in, disrupting, or even hijacking the signal. Just as NSA/CIA have developed a wiki for their work, I think that the west (basically, NATO and a few others) needs a secured internet in which this kind of information is no longer shared outside.
This sounds like it would be useful as a directed energy weapon, especially with the ability to compress waves over a distance.
Ace
... scientists are unable to explain the collapse in numbers of dolphins, whales and other large sea animals in the area...
(captcha word: migrates)
anybody swimming in the North Atlantic is probably glad to see the plane.
One way or another, you are alone in the middle of Atlantic. Perhaps you were on a ship that got into an accident but you managed to escape to a rescue boat.
Then, you finally see a plane. And what does it do? Shoot lasers at you. Perhaps deafen you with massive sonic boom. Not cool!
Give me a way to expand time, so I can experience an hour of clear, cogent subjective thought and action in five or ten minutes of "real" time, and I'll be all over it.
And I promise not to use it for first posts.
Overreporting, troll
Anyone else misread the title as "Navy Scientists Develop Laser for Underwear Communication"?
Potential injury to marine life aside - I'm interested to know how such a system can overcome the extreme variability of seawater. From what I just read this isn't as simple as sonar sending a circular pulse out and getting a 'bounceback'; this is sending information. Surely the abundance of microorganisms, animal matter, let alone local variations in saline and other chemical content which strongly define the physical properties of seawater would be difficult to adjust for?
So it seems this would be a great excuse to put a reasonably high powered laser in space.
It could communicate with submarines over a vast area (I don't mean by illuminating the entire area at once, instead it would target many different pinpoint locations only one of which has the submarine it wants to communicate with).
The enemy wouldn't even be able to follow the track of aircraft that would otherwise be communicating with the submarines.
Instant, high bandwidth communications down to submarines worldwide would solve some real operational problems. (Like in the movie "Crimson Tide"). Unfortunately most schemes to communicate back give away the submarine's position. Perhaps they could modulate the neutrino flux from the nuclear reactors on board?
There are animals in the Ocean that make noises as loud as this..
Take the Pistol Shrimp for example: http://en.wikipedia.org/wiki/Alpheidae
That makes 200db's just by snapping it's big claw.. (albeit at a much shorter range)
Interestingly the 'explosion' caused by the snapping reaches temperatures close to that of the suns surface!
"Never let the truth get in the way of a good story..."
Also, letting people know that there's a sub somewhere within X km (where x is a fairly large number, the sub could hear a 200+ dB signal for a long way) is less useful than you might think. A circle several kilometers in radius is still a pretty big place to look for a sub, if you even happen to have a platform within range that could do the searching.