Weekend Project: Simple Laser Communicator

Secretly shoot your voice across the room on a laser beam in this fun and easy project.
Thanks go to Simon Quellen Field for the original article in Make: Volume 16
To download The Simple Laser Communicator View MP4 click here or subscribe in iTunes.

Check out the complete Simple Laser Communicator article in MAKE: Volume 16 “Simple Laser Communicator”
and you can see that in our digital edition.

Garrett on January 2nd, 2009 at 7:48 am said:

Could this be modified to use a modem as the audio source, and then a modem as the audio receiver on the other end, making for a wireless way to transmit files, text, etc? I’ve always had the idea to do so, but was looking more into PWM lasers & phototransistors for digital comm, rather than analog. Just an idea

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Justin on January 2nd, 2009 at 3:55 pm said:

Garret,

I built one of these a few years ago. The audio quality on the receiving end was not that good. I would imagine the signal is not accurate enough to use with analog signals that a modem would produce. I think it would work with digital signals, since you need must less accuracy on the receiving end.

For digital comm over a laser, it would probably be easier to turn the laser on and off corresponding to 0 and 1. I’m not sure if the circuit in this project would do that, but it would be fairly simple to do with a microcontroller.

You would need to know what speed you can turn the laser on and off in order to determine the maximum rate of transmission. For example, it may take the laser 10ms to power up to full power, then 20ms to power down. So you would need at least 30ms to send 1 bit.

Sounds like a fun project. I would use two microcontrollers, one for transmitting and one for receiving.

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