cathode ray tube

(redirected from CRT monitor)
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cathode ray tube

(hardware)
(CRT) An electrical device for displaying images by exciting phosphor dots with a scanned electron beam. CRTs are found in computer VDUs and monitors, televisions and oscilloscopes. The first commercially practical CRT was perfected on 29 January 1901 by Allen B DuMont.

A large glass envelope containing a negative electrode (the cathode) emits electrons (formerly called "cathode rays") when heated, as in a vacuum tube. The electrons are accelerated across a large voltage gradient toward the flat surface of the tube (the screen) which is covered with phosphor. When an electron strikes the phosphor, light is emitted. The electron beam is deflected by electromagnetic coils around the outside of the tube so that it scans across the screen, usually in horizontal stripes. This scan pattern is known as a raster. By controlling the current in the beam, the brightness at any particular point (roughly a "pixel") can be varied.

Different phosphors have different "persistence" - the length of time for which they glow after being struck by electrons. If the scanning is done fast enough, the eye sees a steady image, due to both the persistence of the phospor and of the eye itself. CRTs also differ in their dot pitch, which determines their spatial resolution, and in whether they use interlace or not.
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Tenders are invited for Supply of Colour CRT Monitor 15",Colour CRT Monitor 17",Colour CRT Monitor 19",Colour CRT Monitor 20",Keyboard,Mouse,Deskjet Printer,Dot Matrix Printer 80 col,Dot Matrix Printer 132 col,Laser Printer (Small) 1000 to 1200 sizes
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The company believed the complainant might not have entered the correct code when ordering his systems, or had selected the CRT monitor when placing his order.
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Worldwide Computer Products News-2 October 2000-Hitachi launches new CRT monitor for business use (C)1995-2000 M2 COMMUNICATIONS LTD http://www.
TELECOMWORLDWIRE-8 October 2001-New 22-inch CRT monitor available from NEC-Mitsubishi (C)1994-2001 M2 COMMUNICATIONS LTD http://www.