from Wiktionary, Creative Commons Attribution/Share-Alike License
- n. a device that transmitted sound on a beam of light
from the GNU version of the Collaborative International Dictionary of English
- n. An apparatus for the production of sound by the action of rays of light.
from The Century Dictionary and Cyclopedia
- n. An instrument by which a beam of light may be made to transmit spoken words to a distance.
Sorry, no etymologies found.
In 1879, Professor Graham Bell, the inventor of the speaking telephone, and Mr Summer Tamter, brought out an ingenious apparatus called the photophone, by which music and speech were sent along a beam of light for several hundred yards.
Bell continued his experiments in communication, which culminated in the invention of the photophone — transmission of sound on a beam of light; in medical research; and in techniques for teaching speech to the deaf.
These included 14 for the telephone and telegraph, 4 for the photophone, 1 for the phonograph, 5 for aerial vehicles, 4 for hydroairplanes, and 2 for a selenium cell.
It took almost fifty years of experimentation to convert Bell's idea for a photophone into a medium that could broadcast Herbert Hoover's speech.
Bell called it a photophone, a device that would allow a person not just to speak to someone else but to look at home in the process.
Jeff Jarvis calls it anonymous instant photophone moblogging, a phrase which is giving me a heavy wallop of jargon vertigo right about now.
In addition, Bell invented the photophone to demonstrate that light could be used to carry sound information, which in turn eventually led to the development of motion pictures with sound.
This is the phenomenon which, as you know, has been utilized by Prof. Graham Bell in that most ingenious and striking invention, the photophone.
By the kindness of Prof. Silvanus Thompson, I have a few slides to show the principle of the invention, and Mr. Shelford Bidwell has been kind enough to lend me his home-made photophone, which answers exceedingly well for short distances.
Bell used the photophone or radiophone over several hundred feet, Ruhmer over several miles.