Sending Music with a Laser Beam

By modifying a laser pen and using a detector you are able to play music over distances that could reach half a mile. To do this the laser needs to be modified by using amplitude modulation. This is then pointed at the sensor which picks up the changes, converts it in to a signal that can be used as music. As with anything with a laser in, be careful when you try anything and do not look at the laser as it could damage your eyes.

To build the device you need to gather together a few components such as a potentiometer, toggle switch and a phototransistor to name a few and then follow the instructions over at Instructables.