Light Emitting Diode

Light Emitting Diodes or LED´s, are the most widely used semiconductor diodes today. They emit fairly narrow bandwidth of energy in the form of light. LED is basically a PN junction diode, made of very thin layer of heavily doped semiconductor material like gallium arsenide phosphide (material determine the color of light). When the diode is forward biased, the negatively charged electrons and positively charged holes combine and release sufficient amount of energy to produce photons that emit light. The amount of photons produced (emitting light) is directly proportional to the current flow. The colour of the light emitted depends on its wavelength and this depends on the band-gap energy of the materials.

LED colours

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