Charles Fritts

Photovoltaic cells. The selenium photographic exposure meter has already been mentioned it goes back to Adams and Day s (1877) study of selenium, was further developed by Charles Fritt in 1885 and finally became a commercial product in the 1930s, in competition with a device based on cuprous oxide. This meter was efficient enough for photographic purposes but would not have been acceptable as an electric generator. 

Solar cell (Charles Fritts) American scientist Fritts designs the first solar cell. 

Charles Fritts makes the first solar cells using selenium wafers... 

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