Photophone

Alexander Graham Bell believed the photophone, not the telephone, was his greatest invention. His photophone carried the spoken voice by reflected sunbeams instead of wire, but did not find any practical application a century ago. Because light has 20,000 times shorter frequency than microwaves, it can carry 20,000 time more information. Only since the onset of ( plastic ) computers has this ability been needed. It would seem that Alex Bell was ahead of his time. 

The rate of PS II electron transport was measured as DCPIP(2/6-dichlorophenol indophenol) reduction using a Hitachi 557 spectrophotometer as described earlier(7). PS I electron transport from the artificial electron donor was assayed as O2 uptake using a Hansatech electrode at 25 C under saturating white light from a slide projector fitted with a 150W Halogen lamp (Photophone Ltd./ India). 

In 1880, the first wireless communication device, the photophone, was developed by Alexander Graham Bell. Guglielmo Marconi, an Italian... 

In 1880, Alexander Graham Bell and American inventor Charles Tainter completed the first telephone conversation, using a wireless phone called the photophone. 

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