OK-4 Laser Communications Using Amplitude Modulation


To demonstrate that a laser can be used for the transfer of data communications, using amplitude modulation of a laser beam.


  • Laser
  • Solar Cell
  • Amplifier and Speaker
  • Radio
  • Amplitude Modulation Unit

Laser Communications


The apparatus is set-up as shown as above. The Amplitude Modulation Unit receives the audio signal from a radio. The output is connected to the modulation input of the laser. The intensity of the laser beam is varied in direct proportion of the audio signal. The receiving solar cell see this as a change in amplitude, thus the receiving speaker-amplifier see this as an audio signal.