#CATHODE RAY TUBE MONITORS TV#

For example, black and white TV screens use one type of phosphor, while color TVs use three (blue, red, and green). By varying the type of phosphor used, one may vary the wavelength of light emitted by the phosphor when excited. These phosphors are struck by incoming electrons from the electron gun, absorb energy, and then re-emit some or all of that energy in the form of light (this process is called phosphorescence). The phosphors in a CRT's screen are the materials that directly produce the photons generated by the CRT. As a matter of safety, the face is typically made of thick lead glass so as to be highly shatter-resistant and to block most X-ray emissions, particularly if the CRT is used in a consumer product. The CRT uses an evacuated glass envelope which is large, deep (i.e., long from front screen face to rear end), fairly heavy, and relatively fragile. The most common uses of phosphors are in CRT displays and fluorescent lights.Īny device that produces a stream of electrons, especially a narrow stream that is focused onto a phosphor screen.Ĭutaway rendering of a color CRT: 1) Three Electron guns (for red, green, and blue phosphor dots) 2) Electron beams 3) Focusing coils 4) Deflection coils 5) Anode connection 6) Mask for separating beams for red, green, and blue part of displayed image 7) Phosphor layer with red, green, and blue zones 8) Close-up of the phosphor-coated inner side of the screen The CRTs in televisions and computer monitors bend the electron beams with magnetic deflection, while oscilloscopes rely on electrostatic deflection.Ī scanning pattern of parallel lines that form the display of an image projected on a cathode-ray tube of a television set or display screen.Ī substance that exhibits the phenomenon of luminescence often transition metal compounds or rare earth compounds of various types.In this case, the persistence of the phosphor is more important than the color. Oscilloscopes, devices used to measure and display voltages, also use CRT displays.Examples of monochromatic CRTs include black and white TVs and old computer terminals. Color CRTs contain three electron guns corresponding to three types of phosphors, one for each primary color (red, blue, and green).

CRT technology used to be common in televisions and computer monitors.

These phosphors are struck by incoming electrons from the electron gun, absorb energy, and then re-emit some or all of that energy in the form of light.

The phosphors in a CRT's screen are the materials that directly produce the photons generated by the CRT.

The primary components of a cathode ray tube (CRT) consist of a vacuum tube containing an electron gun and a screen lined with phosphors.

Cathode ray tube monitors