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New Technology Uses Lasers to Transmit Audible Messages to Specific People

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Re: New Technology Uses Lasers to Transmit Audible Messages to Specific People

#121

Post by monkpit »

jerf wrote: post #98
bryanrasmussen wrote: post #53

Earlier quoted context omitted.

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.

"Consipiracy theorists" have said the government has had this technology for a while. I've considered this particular one to be very likely to be true, because even before this story, it was just so obvious it should be feasible with basic science. I could think of a couple of basic ways to beam "something audible" (not necessarily "sound" but something that would be audible to the system as a whole) into someone's h…

Do you have any sources to back up your claims about supermarket ads?

Re: New Technology Uses Lasers to Transmit Audible Messages to Specific People

#122

Post by ben_w »

balabaster wrote: post #100
dwighttk wrote: post #77

Earlier quoted context omitted.

Also here’s 15 other gravestones to complete your collection.

People who looked at these gravestones also bought these zombie movies.

“… and that led me to werewolves, which is how Amazon turned me into a furry”

Re: New Technology Uses Lasers to Transmit Audible Messages to Specific People

#124

Post by balabaster »

ben_w wrote: post #122
balabaster wrote: post #100

Earlier quoted context omitted.

People who looked at these gravestones also bought these zombie movies.

“… and that led me to werewolves, which is how Amazon turned me into a furry”

Other furries also liked these dog bowls

Re: New Technology Uses Lasers to Transmit Audible Messages to Specific People

#125

Post by 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.

Re: New Technology Uses Lasers to Transmit Audible Messages to Specific People

#126

Post by ecolonsmak »

jlj wrote: post #32

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…

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

Re: New Technology Uses Lasers to Transmit Audible Messages to Specific People

#128

Post by gmueckl »

pontifier wrote: post #73
gmueckl wrote: post #55

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.…

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.

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

Re: New Technology Uses Lasers to Transmit Audible Messages to Specific People

#129

Post by pontifier »

gmueckl wrote: post #128
pontifier wrote: post #73

Earlier quoted context omitted.

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.

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

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.

Re: New Technology Uses Lasers to Transmit Audible Messages to Specific People

#130

Post by gmueckl »

pontifier wrote: post #129
gmueckl wrote: post #128

Earlier quoted context omitted.

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

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.

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.

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