
New Technology Uses Lasers to Transmit Audible Messages to Specific People - webdwarf
https://www.osa.org/en-us/about_osa/newsroom/news_releases/2019/new_technology_uses_lasers_to_transmit_audible_mes/
======
dzink
If you want a sound in your year, you get a device for that. If you are a
business wanting to notify people who trust you, you can give them devices or
blast a speaker. This fills the use case of an actor distributing information
to people who do not have enough contact or trust with that actor or who do
not want the information (because they would willingly use their own device if
they did). Most likely use cases: punitive or targeted spam, punishment
(security alarm, military grade crowd repellent, thief targeting, etc). Also
possible: misinformation, generating confusion and chaos, making people feel
schizophrenic. Weapon in the making. Good uses are also possible - targeted
communication to people who can’t hold devices (surgeon during surgery, vr
headsets, helmet headphones, etc, but that’s too cheap a use case for such an
expensive laser, so weaponization is more likely.

~~~
rkagerer
Those depressing sentiments reflect an unfortunate reality of our time. The
world wasn't always bloated with spammy advertising, and I'm hopeful that fad
will eventually give way to more human-friendly business models.

Yes, any new technology comes with potential for abuse. But I'm still excited
that maybe one day this tech could be miniaturized enough (or deployed
responsibly) to give me wireless virtual earbuds without having to stick
anything in my ear.

~~~
koonsolo
A consumer always pays, whether by paying or looking at advertisements.

But the modern world offers nice alternatives now. I can watch movies and
episodes without ads (thanks to Netflix), and can listen to all the songs in
the world without ads (thanks to Spotify). Because I pay instead of watching
ads.

A lot of platforms and products offer the choice between looking at ads or
letting you pay.

But of course, everyone wants to have stuff for free without ads, but that's
just not how a functional economy works.

~~~
SCHiM
At one point the TV was without ads too!

My point: a netflix with ads will be more profitable than one without. However
they cannot get away with that right now, competition, etc. Maybe never, but
there's a reason ads came around, even for people who paid for television.

~~~
ben_w
It still is, if you watch only the BBC in the UK.

Of course, people still moan about “being forced to pay for it”, even when you
tell them how to legally stop paying for it.

~~~
antepodius
You can't legally not pay for the bbc and then watch, say, ITV, though.

~~~
ben_w
You can if you only watch ITV through thrir online catchup service. When the
UK government closed the “iPlayer loophole”, the new rules covered literally
only BBC iPlayer.

At least, that’s what the TV licencing website says, I don’t know the name of
the actual law so I can’t look it up.

------
webdwarf
Imagine the scary future of retargeting.

\- Doctor, I hear voices in my head

\- Don't worry, it's just ads

~~~
bryanrasmussen
I wonder if you could, with the right combination of technologies, induce
schizophrenia in a subject. Of course since I am in Europe my wondering will
not be turned into a DARPA grant.

~~~
Nasrudith
More fake than induce without the disordered thinking that comes along with
it. Normal people can hallucinate under stress to some degree and it can be
shockingly subtle and non-disruptive. Like thinking their downstairs neighbor
is being noisy but it turns out they were away on vacation.

Interestingly the tone of hallucinations is very culturally shaped - western
ones tend to be more negative.

Artists with schizophrenia tend to produce interesting degrees of abstraction
which seems to be "accidental" as opposed to deliberate. Interesting but sad
of course.

[https://www.bryancharnley.info/self-
portraits-2/charnley_sel...](https://www.bryancharnley.info/self-
portraits-2/charnley_self_portrait_series_01/)

If one wants to cause mental illness we already know how - isolation

~~~
balabaster
The problem is that suspending one's ability to think clearly by preventing
them the silence to do so can have as great an effect on mental illness as
isolation.

------
teekert
Reminds met of the book series Daemon by Daniel Suarez [0], only there they
use nonlinear acoustics to get this effect (if I remember correctly). Nice
books, nice ideas by the way.

Edit: They call it Hypersonic Sound System, not nonlinear acoustics, see [1].

[0]
[https://en.wikipedia.org/wiki/Daemon_(novel_series)](https://en.wikipedia.org/wiki/Daemon_\(novel_series\))
[1] [http://daniel-suarez.com/daemontech.html](http://daniel-
suarez.com/daemontech.html)

~~~
coderintherye
Really great, underrated series. The book was also very prescient in
predicting rise of a distributed digital currency, especially given that it
was published before Satoshi's Bitcoin paper was published.

~~~
teekert
I agree! I have been looking for the same epicness in his later books but it
never hit that level again imho.

------
sparkpeasy
Can't wait till rogue arrays of lasers start beaming advertisements directly
into your ear while walking down the street.

~~~
baroffoos
Why not just play it over a speaker like is often done?

~~~
raihansaputra
Well, now you can directly target people so personalized ads when you're
walking down the street. I'm scared it would devolve to pseudo-hallucinations
('did you hear that?').

~~~
cronix
Or subliminal messages/mind control. I imagine psychiatrist visits would be up
due to this annoying voice in peoples heads. lol.

------
eridius
> _The ability to send highly targeted audio signals over the air could be
> used to communicate across noisy rooms or warn individuals of a dangerous
> situation such as an active shooter._

This strikes me as a rather bizarre example to use. What's special about
active shooters that would warrant using lasers to beam whispered audio
messages directly into someone's ear?

~~~
stereographic
It's just one specific use case for this technology that came to mind for the
researcher? Mass shootings are a pretty big deal, even if the odds of it
happening to anyone is fairly low. Risk mitigation and death prevention seems
like a pretty healthy choice for applying this technology, as opposed to
saying something like "This could let someone beam targeted ads that only the
target can hear!"

"We made this thing, I wonder what we could potentially do with it that would
benefit people as much as possible?"

~~~
jerf
When getting money from the grant system, the grant providers are not neutral
parties objectively deciding what the best science to do is, since there is no
such thing as an objective, neutral party. The grant authors learn to tell the
grant writers what they want to hear.

This is part of why we get such a stream of stories about amazing new
breakthroughs in solar, battery capacity, terrorism reduction, etc. that never
seem to come to fruition. A lot of times they were never for that purpose
anyhow, really; it was just a paragraph tacked on to get the grant.

------
akfish
The principle seems simple. It's too bad that 1.9 μm laser is neither easy nor
cheap to obtain. Otherwise it could be doable for DIYers.

I imagine you can certainly drive people crazy with this thing. For some one
who doesn't know this kind of technology's existence, it's pure magic.

~~~
pmx
There is an alternative method to achieve similar results using very high
frequency (40khz in the case of the video below) audio as a carrier for audio
that is within the human range. It modulates the amplitude of the carrier
signal (in the same way that AM radio does). The high frequency audio
interacts with surfaces it hits and kind 'self decodes' into human-perceivable
audio. It's doable by DIYers with a little electronics knowledge, too!

[https://www.youtube.com/watch?v=aBdVfUnS-
pM](https://www.youtube.com/watch?v=aBdVfUnS-pM)

------
gmueckl
Two big caveats with this tech (from the paper):

\- it's really silent. They claim that the signal is audible, but under pretty
much ideal conditions.

\- creating arbitrary sound with this approach is hard. Each laser sweep
generates a sharp wavefront that is audible, but that only eorks ehen the
sweep is at the speed of sound. This limits the frequency at which you can
emit those pulses and their shape is fixed, too. The only really changeable
property is amplitude.

Not sure if this can be turned into a reasonably high quality source.

~~~
pontifier
They mention 2 methods in the article, the sweep method, and plain old
modulation. If the 2 methods could be combined it might work better.

The sweep could be sped up by several orders of magnitude, and the modulation
could be coordinated with it to create traveling pulse trains toward the
listener that would have higher fidelity.

~~~
gmueckl
The sweep is fixed to the speed of sound or else the whole trick behind it
falls apart. The paper describes that in length.

~~~
pontifier
Yes, but the point of sweeping seems to be to add energy to a traveling wave
front. You can still amplify the wave by sweeping faster and bumping the power
at the appropriate time, but you would gain fidelity because you're not
limited to single square waves.

~~~
gmueckl
No, the amplification can _only_ work at the speed of sound, neither faster
nor slower. The paper analyzes how the wffect falls apart when you deviate
from c.

What you _possibly_ could do is to have multiple laser beams forming a
sweeping comb pattern. Depending on dispersiom and other effects, you might be
able to do some waveform shaping. But that is very elaborate for a
loudspeaker.

~~~
pontifier
That's like saying audio over radio waves can only be sent with spark gaps...
you simulate this "sweeping comb" with a fast sweeping, and even faster
modulating laser.

------
amsdmasdmasdasd
I love all the innovation that's created to warn us about active shooters, all
to let the active shooters keep their guns.

~~~
ams6110
That scenario seems contrived if you ask me. How likely is it that one of
these expensive laser devices will just happen to be available at the scene of
an active shooter incident? And if so, what advantage would it have compared
to general PA announcements?

~~~
balabaster
These are not the robots you're looking for. You can go about your business.

------
segfaultbuserr
There are lots of conspiracy theorists all over the world who suffers from
schizophrenia and other mental disorders, many constantly claim to be the
victims of a secret human experiment project by the governments in the past 30
years. They believe the governments have developed a psychological weapon
which can directly control one's brain and the neural system though
electromagnetic waves, including the ability of sending a "directed voice"
straight to someone's head, and they are subjected to such torture everyday,

Apparently, now their science fiction is finally partially realized...

Of course, the possibility of having a practical weapon is low, while the
chance of these conspiracy theorists being the actual victims of a human
experiment is practically zero. But I personally do believe the R&D of such
psychological weapons do exist, and this is how the non-fictional part of the
conspiracy fiction originated. Related published researches is what they used
as a foundation to justify it, now they just get more materials... And well,
this "mental control" meme has been around since a long time ago, since the
age of radio.

------
rizzin
It would be cool if it were possible to make multicast-like transmissions
using this tech.

I can imagine a rock show where the whole band goes straight into the mixer,
and instead of speakers PA uses this laser tech to transmit the sound to
listeners.

If you are a person who for some reason doesn't receive the transmission, it
must feel very bizarre: the only acoustic sounds would be band playing the
instruments silently, vocalist singing without any amplification, crowd
noises.

It would be a paradise for people making / receiving orders at the bar with
the live music going on.

Or imagine a night club where people on the dance floor receive music very
loudly, but people outside of it receive it at a conversational level.

~~~
door5
This exists with current technology, they're called "silent parties"

------
TeMPOraL
Reminds me of the way AR was implemented in the book Change Agent[0] - there
were devices there using lasers to beam additional visuals directly into your
eye. And, AFAIR, you had to wear laser-blocking glasses when in the city,
because advertisers would abuse this tech to beam ads straight to your eyes.
Anyway, if we could build that, and connect it with (improved version of) the
tech from this article, we could have AR that doesn't require you to actually
_wear_ anything.

\--

[0] - A good biotech sci-fi; I liked it and can recommend it. Speaking of
which, if there are other "biopunk" books out there, I'd love to know.

------
amenghra
There are stories of people having their orthodontic braces act as a radio
antenna. Only the person with the braces would hear something.

This writeup is short:
[https://www.recordonline.com/article/20091118/Health/9111803...](https://www.recordonline.com/article/20091118/Health/911180324).

There's also a (busted) Mythbusters around picking up radio signals thru
fillings.

~~~
diegoperini
It would be so cool if that's the way how radio technology was discovered.

~~~
gmueckl
No, that was absolutely not what happened. The discovery of radio waves
happened in two parts: first, Maxwell completed the fundamental equations for
electrodynamics by postulating that a temporally changing electrical field
must be creating a magnetic field around it. Otherwise the behaviour of plate
capacitors would be inconsistent. This brought the equations into a form that
rather obviously allowed the derivation of a wave equation. Then it took about
20 years IIRC until Hertz managed to prove in his lab that these waves exist
and can be both created and detected.

~~~
diegoperini
Sorry if my bad grammar gave you the impression I thought that is how it was
discovered.

------
vezycash
A sound only I can hear? This could be used to drive someone crazy, commit
suicide or some other horrible task - phishing God.

~~~
entity345
Go on, I'm listening.

\-- The Pentagon

------
onemoresoop
This could not drive anyone insane as it could be easily blocked by covering
the ears or wearing earplugs and it's a good thing..

I could easily see this being adopted by cheaters in passing exams:)

------
darrinm
This would be a nice alternative to headphones/PC speakers for many use cases.
What angle to the ear does it need to be? I.e. can the laser be directly in
front of the listener?

------
jlj
Lasers can also record sounds through window vibrations. Now they can be
targeted transmitters too. They could continuously record and transmit sound
and tailor the messages to real time conversations. Seems like high potential
for abuse.

For example, sharks with giant fricking laser beams that convert shark
thoughts to audible sound that gets louder based on target's voice level.

Or government, millitary, and adtech abuse.

I'm not a big regulations person but see value in them in this case.

~~~
ecolonsmak
Or aim the laser at another drivers rear window and tell that idiot to slow
down!

------
samstave
So, do noise reducing earplugs thwart these things?

and screw the mindset that active shooter is the "cool use case" for something
like this. Jesus christ - if these people had imagination, how about the fact
that it can be uncomfortable to always have a device sitting in your ear canal
- maybe it would make a good headset for a phone conversation sitting at a
desk - you dont need a thing on your head/in your ear to be able to converse
on a call..

------
newman8r
I remember reading about the US military testing a similar technology last
year
[http://blogs.discovermagazine.com/d-brief/2018/03/26/militar...](http://blogs.discovermagazine.com/d-brief/2018/03/26/military-
weapon-laser-voice/)

------
plasma
I remember watching a Ted talk about directional audio "Woody Norris:
Hypersonic sound and other inventions" which focus's audio like a laser.

[https://www.youtube.com/watch?v=HF9G9M0cR0E](https://www.youtube.com/watch?v=HF9G9M0cR0E)
\- very interesting to watch.

------
grizzles
U.S. intelligence had this tech 20 years ago. I'm pretty sure I read about it
on cryptome in the early 2000s.

------
danielecook
I don’t understand it entirely. What do they mean when they say they are
sweeping the laser at the speed of sound?

~~~
gmueckl
This is unintuitive: the laser makes air heat up and expand. This is how the
acoustic waves are created. But this alome is not enough for audible sound.
Higher amplitude is required. They get it by "piling up" a wavefront (in
colloquial terms) by moving the laser exactly as fast as the wave is moving
away. This heats up more air and the additional expansion adds to the already
traveling wavefront.

------
dmckeon
Was this used on US diplomats in Havana?

~~~
cyxxon
No, that was probably just crickets:
[https://www.reddit.com/r/worldnews/comments/acs1zv/the_sound...](https://www.reddit.com/r/worldnews/comments/acs1zv/the_sounds_that_haunted_us_diplomats_in_cuba/)
Thread includes sound samples.

~~~
anon10938750136
That's an hypotesis just as many others. Investigators and medics who visited
the patients say they don't know. Source : yesterday's arstechnica's article:
[https://arstechnica.com/science/2019/01/canada-halves-
diplom...](https://arstechnica.com/science/2019/01/canada-halves-diplomatic-
staff-in-cuba-after-another-mysterious-brain-injury/)

------
zaarn
There is a video on youtube that explains how to do it with ultrasonic
speakers; [https://www.youtube.com/watch?v=aBdVfUnS-
pM](https://www.youtube.com/watch?v=aBdVfUnS-pM)

------
innocentoldguy
This would be great for telling that idiot driving five under in the left lane
to move over, except for cases where I am that idiot. Then it would feel less
great.

------
LifeLiverTransp
Wish we could print plasma coils into the air and energize them. Magnetic
force on demand, wherever you need it.

------
peter_d_sherman
Seems like this would have positive applications in VR/AR/Movie
Theaters/Holodecks...

------
m3kw9
I wonder how the sound fidelity is like, how is the bass response on it?

------
synaesthesisx
Looks like active noise-cancelling headphones are the new Adblock

------
robbas
Thanks osa.org for not spamming me with ads and cookie-popup.

------
phren0logy
[whispered] “advertising” [/whispered]

------
taneq
...or eyeball. :S

Oh, sure, it _says_ it's safe...

------
ziont
i think this might be used to treat people with schizophrenia or other mental
illness issues.

Imagine any negative or false perception can be corrected with a medical
device.

"No, Janet. The butt naked dwarf with a pitchfork isn't real. Keep coding."

------
fukshime
Old school .. whole lot of people say they heard voices in war, and military
mission over 20 years ago

