Optical amplifier
OverviewHistoryLaser amplifiersSemiconductor optical amplifierRaman amplifierOptical parametric amplifier21st centuryImplementations
The principle of optical amplification was invented by Gordon Gould on November 13, 1957. He filed US Patent US80453959A on April 6, 1959, titled "Light Amplifiers Employing Collisions to Produce Population Inversions" (subsequently amended as a continuation in part and finally issued as U.S. patent 4,746,201A on May 4, 1988). The patent covered “the amplification of light by the stimulated emission of photons from ions, atoms or molecules in gaseous, liquid or solid state.” In total, Gould obtained 48 pa