"All technology can be used for bad or good. It's up to you how to use it."
Vladimir Zworykin, scientist
In 1930, the Soviet Russian physicist Leonid Kubetsky (1906-1956) proposed a method to amplify weak photoelectric currents. He exploited the photoelectric effect where the energy of photons is converted into the energy of moving electrons. These electrons can then be accelerated. When these electrons impact a fluorescent plate, several photons are then dislodged, converting the energy back into visible light. The device, a photomutliplier tube, can increase the illumination fifty-fold. Used in series, these tubes can create a cascade of photons, producing gains in excess of 50,000-fold illumination.
In the 1930s, Vladimir Zworykin (1889-1982) was working at RCA on what became the first commercially viable television. To overcome the problem of a weak signal, Zworykin employed a similar photomultiplier. It was Zworykin's design, produced in 1936, that became commercially successful, and Kubetsky is largely forgotten outside of the former U.S.S.R.
The military quickly saw the potential of these devices. Working with G. A. Morton, at RCA, Zworykin developed the first generation of night vision devices. These devices sensed infrared light, which is invisible to the unaided human eye. The photomultiplier tubes found use in astronomy in 1937 so that the weak visible light from distant stars could now be seen. The tubes were also employed in medical imaging.
