LED
A Light Emitting Diode (LED) is a semiconductor that has the ability to emit light when electrically stimulated (this is called electroluminescence).
In the semiconductor there are two areas, an n-conductive area with a surplus of electrons and a p-conductive area with a deficit of electrons. In the border area – known as the p-n junction or barrier layer – light is generated by a process of recombination, which is triggered when direct current is connected to the semiconductor and the electron surplus and deficit are evened out. The colour of the light is determined by the materials used in the manufacture of the diode. Basic colours are red, orange, green and blue in different shades.
LEDs are available as small single-chip versions that require mounting on some form of printed circuit board, and versions with multiple LEDs closely arranged on a single card. The latter are called LED modules.
Read more in the PDF document below.
