Noun
English Wikipedia has an article on:phototubeWikipedia
phototube (plural phototubes)
A gas-filled electron tube that has a photosensitive cathode.
Electron multipliers A photomultiplier is a phototube whose sensitivity is greatly increased through the use of electron multiplication. Source: Internet
For example, the yield of a phototube is measured in phe/keVee ( photoelectrons per keV electron-equivalent energy). Source: Internet
For example, an increase in frequency results in an increase in the maximum kinetic energy calculated for an electron upon liberation – ultraviolet radiation would require a higher applied stopping potential to stop current in a phototube than blue light. Source: Internet
His experiment directly measured potentials, not electron kinetic energy: he found the electron energy by relating it to the maximum stopping potential (voltage) in a phototube. Source: Internet