katooditoru

Katooditoru is the Estonian term for a cathode ray tube, a sealed vacuum device used to display images in traditional CRT displays such as older televisions and computer monitors. A katooditoru consists of a glass envelope containing an electron gun, a high-voltage anode, and a phosphor-coated screen. The electron gun heats a cathode to emit electrons, which are accelerated toward the screen by the anode voltage. A deflection system, typically a magnetic yoke, steers the beam so that it scans the screen in a left-to-right, top-to-bottom raster pattern. In color versions, three electron guns illuminate red, green, and blue phosphors, with a shadow mask or aperture grille ensuring correct color alignment and preventing crosstalk.

Image brightness and hue are controlled by the intensity of the electron beams and the composition of the phosphors. The result is an analog, continuously variable image. Monochrome CRTs used a single gun and a single phosphor layer, while color CRTs used multiple beams and filtering.

CRT displays were common from the mid-20th century through the early 2000s, offering wide viewing angles and fast response but being bulky, heavy, and power-hungry. They have largely been displaced by flat-panel technologies such as LCD and OLED, though some specialized equipment and vintage systems remain in use.

Safety considerations include shielding for X-rays generated by high-velocity electrons and environmental concerns related to recycling lead-containing glass and phosphors.