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.
