Katodisädeputkia

Katodisädeputkia, known in English as cathode ray tubes (CRTs), are vacuum tubes in which a beam of electrons is accelerated and deflected onto a fluorescent screen, causing it to glow. This technology was fundamental to the development of early electronic displays, particularly for televisions and computer monitors. The basic principle involves an electron gun at the rear of the tube that emits and focuses electrons into a narrow beam. This beam then passes through deflection coils or plates, which manipulate its direction. In color CRTs, three electron beams are used, each corresponding to a primary color (red, green, and blue). The inner surface of the screen is coated with phosphors that emit light when struck by electrons. The intensity and color of the light are controlled by modulating the electron beams. CRTs were widely used from the mid-20th century until the early 21st century, gradually being replaced by newer display technologies like LCD and OLED due to their bulk, power consumption, and limitations in resolution and refresh rates. Despite their obsolescence in consumer electronics, the principles behind CRTs laid the groundwork for many subsequent display technologies.