"electron gun." YourDictionary, n.d. Web. 07 December 2018. <https://www.yourdictionary.com/electron-gun>.
electron gun. (n.d.). Retrieved December 07th, 2018, from https://www.yourdictionary.com/electron-gun
The part of a cathode-ray tube that emits a narrow beam of electrons, consisting of a cathode, control grids, and usually a heater. Electrons are emitted from the cathode, which is typically heated by electric current to give the electrons escape energy. The electrons are then focused into a beam by the electric fields of the control grids.