All the magnificent colors that
can be seen on the television screen are formed from the
three primary colors - Red, Green and Blue.
The TV screen is coated with phosphor dots that glow with
color when they're hit with a stream of electrons. The dots
are arranged in sets of three to produce three colors of
light - red, blue and green. One end of the picture tube
contains electron guns.
These guns spray electrons onto the phosphor dots. When
electron hit the dots, the dots glow with color and a picture
appears on the screen. Electron beams in the television
strike the phosphor dots on the screen giving rise to a
dazzling display of colors.
All the colors one sees on the screen are made up of red,
blue and green lights.
A color television set produces colored light and close
examination of the lit screen reveals that it contains patterns
of red, green and blue dots or stripes. At a distance, the
dots or stripes merge into a color picture. But close up,
the yellow light can be seen to be made up of red light
and green light.
If you are still unclear about the concepts, please refer
the animation below.