Can you use Light as an Information Transmission Medium?

Do you think its possible to use light as a transmission signal source? For example, we use radios, cell phones, etc and those are all sent through electromagnetic radiation or what not, (correct me if I'm wrong) but instead, substituting electromagnetic radiation for Light as your transmission signal source. This would be more for space travel and exploration issues in order to get the signals from the space ship back to earth faster.
- Curtis Koehn (age 22)
Eagle, WI, USA

Sure.   Modulation of light has been used for years to transmit information, starting with old fashioned on-off Morse code signals used by the Navy in the stone age to the present day fiber cable systems that can transmit gigabytes worth.   You can also modulate a simple laser signal and transmit information without the wires, but you need a direct line of sight path.    
By the way, light is an electromagnetic phenomenon, just like ordinary radio or television waves.   The frequencies are, however, much higher.  Light and ordinary radio waves travel at the same speed.

LeeH

(published on 05/30/2013)