vacuum tube

/ˌvækjəm ˈtub/

Other forms: vacuum tubes

Definitions of vacuum tube

1. noun

   electronic device consisting of a system of electrodes arranged in an evacuated glass or metal envelope
   synonyms: electron tube, thermionic tube, thermionic vacuum tube, thermionic valve, tube

   types:

   acorn tube

   a small vacuum tube; used at high frequencies

   diode, rectifying tube, rectifying valve

   a thermionic tube having two electrodes; used as a rectifier

   electron multiplier

   a vacuum tube that amplifies a flow of electrons

   gas-discharge tube

   a tube in which an electric discharge takes place through a gas

   klystron

   an electron tube used to generate or amplify electromagnetic radiation in the microwave region by velocity modulation

   magnetron

   a diode vacuum tube in which the flow of electrons from a central cathode to a cylindrical anode is controlled by crossed magnetic and electric fields; used mainly in microwave oscillators

   pentode

   a thermionic tube having five electrodes

   television pickup tube, television-camera tube

   a tube that rapidly scans an optical image and converts it into electronic signals

   tetrode

   a thermionic tube having four electrodes

   triode

   a thermionic vacuum tube having three electrodes; fluctuations of the charge on the grid control the flow from cathode to anode which makes amplification possible

   X-ray tube

   a vacuum tube containing a metal target onto which a beam of electrons is directed at high energy for the generation of X rays

   CRT, cathode-ray tube

   a vacuum tube in which a hot cathode emits a beam of electrons that pass through a high voltage anode and are focused or deflected before hitting a phosphorescent screen

   glow lamp

   a gas-discharge tube with a hot cathode; used in stroboscopes

   glow tube

   a gas-discharge tube consisting of a cold cathode and a diode in a tube filled with gas; the color of the glow depends on the particular gas

   iconoscope

   the first practical television-camera for picture pickup; invented in 1923 by Vladimir Kosma Zworykin

   image orthicon, orthicon

   a now obsolete picture pickup tube in a television camera; electrons emitted from a photoemissive surface in proportion to the intensity of the incident light are focused onto the target causing secondary emission of electrons

   type of:

   electronic device

   a device that accomplishes its purpose electronically