Editing Alexander Graham Bell (section)

===Photophone===
{{Main|Photophone}}
[[File:Photophony1.jpg|thumb|Photophone receiver, one half of Bell's wireless [[optical communication]] system, ca. 1880]]

Bell and his assistant [[Charles Sumner Tainter]] jointly invented a wireless telephone, named a [[photophone]], which allowed for the transmission of both sounds and normal human conversations on a beam of [[light]].{{sfn|Bruce|1990|p=336}}<ref name="SDU">{{cite web|last=Jones |first=Newell |url=http://history.sandiego.edu/gen/recording/ar304.html |archive-url=https://web.archive.org/web/20020219111153/http://history.sandiego.edu/gen/recording/ar304.html |url-status=dead |archive-date=February 19, 2002 |title=First 'Radio' Built by San Diego Resident Partner of Inventor of Telephone: Keeps Notebook of Experiences With Bell |location=San Diego, California |website=Evening Tribune |date=July 31, 1937 |access-date=November 26, 2009 }}</ref> Both men later became full associates in the [[Volta Laboratory and Bureau#Laboratory projects|Volta Laboratory Association]].

On June 21, 1880, Bell's assistant transmitted a wireless voice telephone message a considerable distance, from the roof of the [[Franklin School (Washington, D.C.)|Franklin School]] in Washington, D.C., to Bell at the window of his laboratory, some {{convert|213|m|round=5|order=flip}} away, 19 years before the first voice radio transmissions.{{sfn|Carson|2007|pp=76–78}}{{sfn|Bruce|1990|p=338}}<ref>{{cite journal|last=Groth |first=Mike |url=http://www.bluehaze.com.au/modlight/GrothArticle1.htm |title=Photophones Revisted |journal=Amateur Radio |date=April 1987 |pages=12–17 |access-date=September 19, 2015 |url-status=dead |archive-url=https://web.archive.org/web/20150802001855/http://www.bluehaze.com.au/modlight/GrothArticle1.htm |archive-date=August 2, 2015 }}</ref><ref>{{cite journal |last=Mims III |first=Forest M. |url=https://books.google.com/books?id=zoaSp1BJu50C |title=The First Century of Lightwave Communications |journal=Fiber Optics Weekly Update |date=February 10–26, 1982 |pages=11 of 6–23 }}</ref>

Bell believed the photophone's principles were his life's "greatest achievement", telling a reporter shortly before his death that the photophone was "the greatest invention [I have] ever made, greater than the telephone".<ref>{{cite encyclopedia |last1=Phillipson |first1=Donald J.C. |first2=Laura |last2=Neilson |title=Alexander Graham Bell |encyclopedia=[[The Canadian Encyclopedia]] |publisher=[[Historica Canada]] |edition=online |date=March 4, 2015 |url=https://www.thecanadianencyclopedia.ca/en/article/alexander-graham-bell |access-date=September 19, 2015 |archive-date=September 25, 2015 |archive-url=https://web.archive.org/web/20150925112928/http://www.thecanadianencyclopedia.com/en/article/alexander-graham-bell/ |url-status=live }}</ref> The photophone was a precursor to the [[fiber-optic communication]] systems which achieved popular worldwide usage in the 1980s.<ref>{{cite report|last=Morgan |first=Tim J. |title=The Fiber Optic Backbone |publisher=[[University of North Texas]] |date=2011 |url=https://classes.lt.unt.edu/Summer_10W_2011/LTEC_4550_020/tjm0146/Fiber%20Optic%20Backbone%20.docx |archive-url=https://web.archive.org/web/20150925132141/https://classes.lt.unt.edu/Summer_10W_2011/LTEC_4550_020/tjm0146/Fiber%20Optic%20Backbone%20.docx |url-status=dead |archive-date=September 25, 2015 |access-date=September 19, 2015 }}</ref><ref name="AmericanScientist-1984.V72.No1">{{cite journal |last=Miller |first=Stewart E. |jstor=i27852430 |title=Lightwaves and Telecommunication|journal=[[American Scientist]] |volume=72 |issue=1 |date=January–February 1984 |pages=66–71|bibcode=1984AmSci..72...66M }}</ref> Its master patent was issued in December 1880, many decades before the photophone's principles came into popular use.