Light
emitting diode (LED): A light emitting diode (LED) is a diode
that gives off visible light when forward biased.
The
construction and operation of LED: Charge carrier
recombination take place at a p-n junction as electrons cross from the n-side
and recombine with holes on the p-side. Free electrons are in the conduction
band of energy levels while holes are in the valance band.
Therefore
electrons are at a higher energy level than holes and some of this energy is
given up in the form of heat and light when recombination takes place. If the
semiconductor material is translucent the light will be emitted and the
junction becomes a light source i.e. a light emitting diode (LED).
Figure:
LED
No comments:
Post a Comment