gcse physics P3 electron beam guns in tv's

How is an electron beam used in old tv’s

An oscilloscope uses deflection plates to control the path of electrons. In Tv’s a similar process happens but with tube electromagnets. This is found in the CRT (cathode ray tube). Electromagnets deflect the electrons in zig zags across and down the screen, making 625 horizontal lines before returning to the start. Every 1/25 of a second the screen is scanned by an electron beam. The picture consists of three separate pixels of colour. 

A colour TV consists of three electron guns; one for every basic colour of the electromagnetic spectrum (red, blue and green). All other colours can…