- cathode-ray tube
/kath"ohd ray'/a vacuum tube generating a focused beam of electrons that can be deflected by electric fields, magnetic fields, or both. The terminus of the beam is visible as a spot or line of luminescence caused by its impinging on a sensitized screen at one end of the tube. Cathode-ray tubes are used to study the shapes of electric waves, to reproduce images in television receivers, to display alphanumeric and graphical information on computer monitors, as an indicator in radar sets, etc. Abbr.: CRT[1900-05]
* * *Vacuum tube that produces images when its phosphorescent surface is struck by electron beams. CRTs can be monochrome (using one electron gun) or colour (typically using three electron guns to produce red, green, and blue images that, when combined, render a multicolour image). They come in a variety of display modes, including CGA (Color Graphics Adapter), VGA (Video Graphics Array), XGA (Extended Graphics Array), and the high-definition SVGA (Super Video Graphics Array).
* * *