LED | Light Emitting Diode

The light emitting diode, which is better known by the English acronym 'LED', has been revolutionary in lighting. Its applications are vast, such as microelectronics, signage, displays / panels; and even as invention associated with the Nobel Prize this year. http://goo.gl/DJODJj


The LED is a semiconductor diode that when receiving electricity emits visible light (electroluminescence). The emitted light is not monochromatic but its color mainly depends on the crystal and the impurity which it is placed.

The red LED of high efficiency, was produced in 1962 and their constitution there is a GaAsP compound, or consists of a Gallium Arsenide crystal (GaAs) with doping phosphorus (P).
The green LED of high efficiency, was produced in 1972 and their constitution there is AlGaP compound, or consists of a gallium phosphate crystal with aluminum.
The blue LED, broadband, was produced in 1994 and their constitution there is InGaN compound, or consists of a crystal gallium nitride (GaN) doped with indium (I).

The Wikipedia site presents us with a elaboradíssima page on this topic, which we recommend reading: http://goo.gl/GIFNh2