electron gun
Noun
Meaning
the electrode that is the source of electrons in a cathode-ray tube or electron microscope; consists of a cathode that emits a stream of electrons and the electrostatic or electromagnetic apparatus that focuses it
Source: WordNetSynonyms
Hypernyms
Examples
In a monochrome receiver the luminance signal is amplified to drive the control grid in the electron gun of the CRT.
In some systems this was accomplished using a second electron gun inside the CRT that could write to one location while the other was reading the next.
It differs from a normal CRT in that the electron gun within does not produce a focused controllable beam.
Provided the electron gun can generate a beam with sufficiently small diameter, an SEM could in principle work entirely without condenser or objective lenses, although it might not be very versatile or achieve very high resolution.
When the main electron gun writes an image to the screen, the energy in the main beam is sufficient to create a 'potential relief' on the storage mesh.