Picture Tubes

Picture Tubes

Picture tubes, also known as cathode ray tubes (CRTs), are electronic devices used in televisions and computer monitors to display images. The technology behind picture tubes dates back to the late 19th century, when scientists discovered that a stream of electrons could create a visible light when striking a phosphorescent material. The first practical application of this technology was the cathode ray oscilloscope, which was used to display electrical signals in laboratories. Picture tubes work by using an electron gun to shoot a beam of electrons at a phosphorescent screen. The electron gun is located at the back of the tube and consists of a cathode, which emits electrons, and an anode, which accelerates the electrons towards the screen. The beam of electrons is focused and directed by a series of magnetic fields, which determine the position and intensity of the image on the screen. The phosphorescent screen is coated with a material that emits light when struck by the electrons. Different materials produce different colors of light, so picture tubes use a combination of red, green, and blue phosphors to create a full-color image. The intensity of the electron beam determines the brightness of the image, while the position of the beam determines the shape of the image. Picture tubes were the dominant technology for television and computer monitors for many years, but they have largely been replaced by newer technologies such as LCD and OLED displays. However, picture tubes are still used in some specialized applications, such as medical imaging and industrial equipment.

cathode ray tubes, electron gun, phosphorescent screen, magnetic fields, full-color image

— Anthony Martinez

CITATION : "Anthony Martinez. 'Picture Tubes.' Design+Encyclopedia. https://design-encyclopedia.com/define/picture-tubes?E=383580 (Accessed on October 13, 2026)"