Design and functioning of a refresh cathode ray tube

Primary components of refresh cathode ray tube are

(i) electron gun used in producing electron beam

(ii) heating filament, used to heat up the cathode for emission of electrons

(iii) focusing system used in making the electrons converge to one point on the screen

(iv) magnetic deflection coils for making a specific point on the screen as the focus of electron beam

(v) phosphor coated screen, where the electron beam strikes and transfers its kinetic energy to phosphor atoms, which in their turn convert the energy to optical energy and a picture cell (pixel) is grown (evoked)

(vi) a control grid to control the intensity of electron beam which is governed by the number of electrons passing through the control grid.