3 ms·
The technique of using light to transmit sound has been around for over half a century.. although it's more commonly used as a microphone rather than a speaker.
by kjaftaedi 7y ago
The technique of using light to transmit sound has been around for over half a century.. although it's more commonly used as a microphone rather than a speaker.
https://en.wikipedia.org/wiki/Laser_microphone https://en.wikipedia.org/wiki/Laser_microphone
A microphone is just a reverse speaker. For example, if you plug your earbuds into an audio input port, you can use them as a microphone.
This is all relatively basic, just not obvious to most people.
- jml7c5 7y agoI am not sure it is really as basic and obvious as you imply. The comparison between the "reversibility" of laser speakers/microphones and the reversibility of normal speakers/microphones is a bit off, in my opinion. For starters, laser microphones do not use the photoacoustic effect[1] that the device described relies upon. Whereas the reversibility of normal speakers/microphones is because both devices use the same physical process. That it's possible to build a microphone using lasers and to build a long-range sound generating device using a laser doesn't imply it's obvious (or even possible) to do so for any given audio production or recording technique. E.g., if I can generate audio using a flickering lightbulb, it is not clear that a flickering lightbulb can be used as a microphone. [1]: https://en.wikipedia.org/wiki/Photoacoustic_effect https://en.wikipedia.org/wiki/Photoacoustic_effect