I can hear the light! Boffins beam audio into ears with freakin' lasers

MIT boffins have used low-power lasers to beam audio directly into a subject's ear. The technique relies on the interaction between light and water in the air, a phenomenon known naturally enough as the "optoacoustic effect". In their experiments, the researchers found they could use this to transmit an audio signal which, …

[Anonymous Coward]

So...

That's where the strange voices are coming from that I keep hearing in my head !

[TeeCee]

Re: So...

No, that's from the miniature radios that the Illuminati implanted in your teeth.

[Anonymous Coward]

I assume...

You could eavesdrop on the energy/radio emissions of the laser instead? XD

[phuzz]

Re: I assume...

My first thought that if they're scanning the laser with a moving mirror, that you'd probably be able to hear a faint sound from the mirror itself.

[Blockchain commentard]

Surely if you can make a noise with lasers, just reverse it and you can pick up the audio from the vibrating air/water molecules? Simple science at it's best !!!

[teknopaul]

I've heard it said you can do that with laser on glass to listen to what is going on in a room across the block.

Trouble with doing that with water molecules is you need ones that apart from the sound are otherwise stable.

[DCFusor]

You can, but

The glass has terrible frequency response - the mass makes it a good low pass filter.

The room reverb is horrible - even with a good microphone at many feet from the talker in those big rooms adversaries leaders and diplomats favor with lots of reflective surfaces that don't absorb echos.

Other vibrations - passing cars, HVAC, elevators and what not....shake the glass really well.

Back in the day I helped write some code to deconvolve that kinda stuff....success was pretty iffy.

[M.V. Lipvig]

I imagine that if they are announcing that it's possible, it's because they got it to work. Pretty neat stuff.

All you need to prevent laser eavesdropping is a vibrating sex toy taped to the glass Stops the eavesdropper while sending them a message about what they can go do to themselves.

[Chris G]

@ Blockchain commentard.

A couple or three decades back I heard of an intelligence agency that was experimenting

with non visible lasers to read the CO2 from breath in the hope they could fire their lip readers.

[Jason Bloomberg]

Kaboom

Why am I reminded of the film "Scanners" and left wondering how many rats were scraped into bins while they determined an appropriate laser wavelength to use?

[Will Godfrey]

Shocked!

I feel sorry for all those poor people sent off to the loony bin when they really were hearing voices while nobody was there.

[Primus Secundus Tertius]

Surely some mistake

16MHz as an electromagnetic wave would have a wavelength of about 19 metres, not 1.9 microns.

[ThatOne]

Re: Surely some mistake

Definitely: 16 MHz would be the decameter shortwave radio band. Some laser.

Fortunately the real article's abstract helps: It mentions they used a "1.9 μm thulium laser".

[M. Poolman]

Re: Surely some mistake

Many zeroes dropped, I make it ~160THz

[Suricou Raven]

MHz?

I think someone lost a few zeros.

[dbayly]

Ain't science wonderful ?

Oh, finally - advertisements beamed to your ears only! And other delightful applications.

[Jess--]

Re: Ain't science wonderful ?

That was my first thought too.

walking past shops could become very annoying.

driving towards an unscrupulous garage could result in unusual noises seeming to come from your car

[Chris 69]

Damn!

I wish I'd thought of that. Seriously cynical old git that I am.

[VikiAi]

Re: Ain't science wonderful ?

You just have to buy my special dark glasses for your ears!

[John Brown (no body)]

Re: Ain't science wonderful ?

Yeah, The Space Merchants was supposed to be a warning of a dystopian future, not an instruction manual.

[Flak]

Freeze!

Not the water in the air, just don't move if you want to hear.

It will be interesting to see if there will be a real world use case at some point, or whether this will stay in the lab.

Love reading articles like this - technology applied in really creative ways - just because you can!

[mosw]

Re: Freeze!

Why would you have to stay still? I would think that having ceiling mount lasers tracking your movement would be well within the capability of current technology.

In some dystopian future I could see Google/Amazon installing such a system in your local mall so it can whisper personalized purchase suggestion in your ears as you walk around.

[Andytug]

Oh great, laser headphones...

Think of how many ignorant audiophiles they'll be able to fleece with those...until they find out they only work if you sit in exactly the right chair and keep your head perfectly still.....

[Evil Auditor]

Re: Oh great, laser headphones...

you sit in exactly the right chair and keep your head perfectly still

I thought exactly that was the gist of being ignorant audiophile. Besides The Cables, of course.

[Korev]

Re: Oh great, laser headphones...

Audiophiles? What's in a Naim?

[Anonymous Coward]

Re: Oh great, laser headphones...

"Think of how many ignorant audiophiles they'll be able to fleece with those..."

Obviously you can't hydrate the air in your acoustic onanism room with plain old ordinary water - you need to buy very special oxygen free water containing homeopathic concentrations of pure gold, otherwise the spectral laser frequency's dynamic response will be adversely affected by the laser's inverse reverberant resonance simulacrum.

Everyone knows that...

[Zimmer]

Re: Oh great, laser headphones...

"Think of how many ignorant audiophiles they'll be able to fleece with those...until they find out they only work if you sit in exactly the right chair and keep your head perfectly still....."

You're in my spot.....

..it's the T-shirt with 73 on it..

[Alistair]

All the chuckles aside, I'm wondering about the real world uses like most here ?hear? ....

I know a couple of folks who *really* cannot wear headphones or earbuds. (autism can have some wonderful quirks) but would love to have music whilst working (I share this trait of being able to focus better while having music playing .... it helps with my ADD), and generally cannot have this as it becomes an environment conflict. (i.e they are allowed to have headphones or earbuds, cannot wear them due to physical reaction or as in my SO's case earbuds just *do not* stay in place due to the shape of her ears)

I actually wonder if the arrangement could be made light enough and non-constrictive enough to solve their issues.

But then I am a bit weird.

I suppose the other application would be to communicate verbally with the herd of laser equipped sharks.

[TRT]

I can haz music in the en-suite shower without cranking up the volume to the point where it wakes the sleeping beauty! Beam the laser down the water pipe using it as a kind of waveguide. Just don't start singing or you'll nullify the whole point of it.

[TRT]

Shoal.

[Swarthy]

For the folks that cannot wear headphones or earbuds; they may be interested in transducer (bone conductivity) headphones. They don't sit in/on the ears, but rather just in-front/behind them, so may not invoke the same sensory reaction.

[Toltec]

This is the voice of the Mysterons.

[0laf]

Nooo

the govenment is beaming words into my head!

[Evil Auditor]

Re: Nooo

What a time for being paranoid!

A while ago I considered giving it up. But now, most certainly not!

[MiguelC]

"optoacoustic effect"

They lost that once-in-a-lifetime opportunity of using the confusing - although correct - term "optootic effect"

It'd make those boffins read twice, wouldn't it?

[ratfox]

Hearing light? That's nothing

This guy can see noises

[Tridac]

Re: Hearing light? That's nothing

That was in the 60's, but different source...

[DubyaG]

Sharks!

Perhaps this is how sharks communicate? They have lasers, right?

[eldakka]

Re: Sharks!

Does this mean a school of sharks with frickin laser beams on their heads has been re-designated as an orchestra?

[Anonymous Coward]

LSD

Oh, great, just one more way to replaced LSD. "Oh, man, did you hear those colors?"

[LateAgain]

Gotta ask

Does it melt the earwax ?

[David Roberts]

Melt the earwax?

Not if you use mirror finish ear plugs.

La la la........

[Fred Flintstone]

I know some folks ..

.. where the beam would just leave via the other ear.

That said, I would never trust them near anything with a laser to start with. I even worry that they will at some point discover their mice are optical.

[anthonyhegedus]

There’ll only be two use cases for this:

1. Listen to soothing music through your skin whilst being tatooed by a giant laser or having your earwax hygienically vapourised.

2. Adverts. These ads will also know if you’ve been listening by detecting subtle changes in body temperature and pulse. If you haven’t been listening, the advert is repeated incessantly until you have. Or until you agree to buy whatever it is that’s being advertised monthly.

[Dimmer]

Weather control?

Or how about a tractor beam, have you seen the audio box where the modulated sound waves coming from speaker on the walls are used to move objects in 3 dimensions?

How about a sound based defense shield?

[M.V. Lipvig]

Oh no, not #2! That would result in people being driven to burn down ad agencies and factories to put their tormentor out of business!

[Anonymous Coward]

Dancefloors?

Could this be used to keep the music loud on the dancefloor, but quiet enough to speak over in the rest of the club?

[Swarthy]

Re: Dancefloors?

I think decent baffles and audio engineering might be cheaper. Some decent electrostatic speakers would have a similar effect, but they might not be cheaper.