CRT TV
CRT TV is an image-receiving device that uses cathode rays. It was widely used as a TV receiver until the mid-2000s. However, it had the disadvantage of being large and heavy. Afterward, it gradually disappeared as LCD and OLED TVs replaced it and is now only used in a few particular purpose.
How CRT TV works
The cathode-ray tube operates in the following sequence.
- The Electron gun emits an electron beam.
- A deflection coil (deflection yoke) bends the electron beam. (Electron beams are like (-)currents and are bent by magnetic fields.)
- The electron beam reaches a screen (surface of the cathode ray tube) coated with a fluorescent material.
- The fluorescent material changes the energy of the electron beam into visible light. As a result, the pixel glows at the desired brightness.
- The screen reveals an image gradually by changing the magnetic field of the deflection coil.
- The above operation is repeated dozens of times per second.
