Working Principle of CRT

      The electrons emitted from the cathode makes an electron cloud. This electron cloud then forms the electron beam. This electron beam then with the help of the yoke or the combined horizontal and vertical scanning coil moves left-right and up-down. By this process the beam hit the screen of the CRT. As the CRT has many dots which are light sensitive and coated with the phosphors. The phosphor chemicals are light metals as Zinc (Zn) and Cadmium (Cd) in the form of Sulphide, Sulphate and Phosphate compounds.

By processing these materials a fine particle is formed  and then applied t the inside of the tube. When the high velocity beam strikes the screen the corresponding dot or spot fluoresces and emits light. This light comes to eye make a visible picture.

Application of the CRT:

                   

In actual practice CRT is a very common feature in every devices which need to represent any data visibly. CRT is mostly used in the following devices:

1)  Television Set

2)  Computer monitor

3)  Oscilloscope

4)  Electrocardiograph (ECG) machine

5)  RADAR etc.