PhotophoneIn 1880, Alexander Graham Bell transmitted the first wireless telephone message on his newly-invented photophone. The photophone worked by projecting his voice through an instrument towards a mirror. The vibrations in the voice caused similar vibrations in the mirror. Bell directed sunlight into the mirror, which captured and projected the mirror's vibrations. The vibrations could be deconstructed back into sound at the receiving end of the projection. In this way the photophone functioned similarly to the telephone; the difference was that the photophone used light as a means for projecting the information, while the telephone used electricity. |
