oxide rectifier การใช้

The development of selenium rectifiers began during the early 1930s, and these replaced copper oxide rectifiers because they were more efficient.
Compared with the earlier copper oxide rectifier, the selenium cell could withstand higher voltage but at a lower current capacity per unit area.
Compared to later silicon or germanium devices, copper-oxide rectifiers tended to have poor efficiency, and the reverse voltage rating was rarely more than a few volts.
By 1938, Boris Davydov had developed a theory of the copper-oxide rectifier, identifying the effect of the p n junction and the importance of minority carriers and surface states.
One of the earliest suitable rectifiers was the copper oxide rectifier developed and manufactured by Union Switch & Signal Company, Swissvale, Pennsylvania, later part of Westinghouse Brake and Signal Company, from 1927.