Electron gun

An electron gun (also called electron emitter) is an electrical component in some <a href="/facts/Vacuum_tube/VHd1BNLq">vacuum tubes</a> that produces a narrow, <a href="/facts/Collimation/lhd2hhPt">collimated</a> <a href="/facts/Electron_beam/9jRXSquS">electron beam</a> that has a precise <a href="/facts/Kinetic_energy/aJRxUd4p">kinetic energy</a>.
The largest use is in <a href="/facts/Cathode-ray_tube/8NVGx5C7">cathode-ray tubes</a> (CRTs), used in older <a href="/facts/Television_set/8moTsqhB">television sets</a>, <a href="/facts/Computer_display/NRaTDFHc">computer displays</a> and <a href="/facts/Oscilloscope/HMdD8XVk">oscilloscopes</a>, before the advent of <a href="/facts/Flat-panel_displays/jw0LWETN">flat-panel displays</a>. Electron guns are also used in <a href="/facts/Field-emission_display/9ekcmGvg">field-emission displays (FEDs)</a>, which are essentially flat-panel displays made out of rows of extremely small cathode-ray tubes. They are also used in microwave linear beam <a href="/facts/Vacuum_tube/VHd1BNLq">vacuum tubes</a> such as <a href="/facts/Klystron/xYeQ0nId">klystrons</a>, <a href="/facts/Inductive_output_tube/llppCCSn">inductive output tubes</a>, <a href="/facts/Travelling-wave_tube/rlgg9KSN">travelling-wave tubes</a>, and <a href="/facts/Gyrotron/s0rHKtnm">gyrotrons</a>, as well as in scientific instruments such as <a href="/facts/Electron_microscope/XtaBktwF">electron microscopes</a> and <a href="/facts/Particle_accelerators/Pkuc08xC">particle accelerators</a>.
Electron guns may be classified by the type of electric field generation (DC or RF), by emission mechanism (<a href="/facts/Thermionic_emission/3oujvv1U">thermionic</a>, <a href="/facts/Photocathode/XPcNlAjs">photocathode</a>, <a href="/facts/Field_electron_emission/ReNmucpE">cold emission</a>, <a href="/facts/Plasma_(physics)/1d3btMVU">plasmas</a> source), by focusing (pure electrostatic or with magnetic fields), or by the number of electrodes.

Electron gun open-in-new

Electron gun