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How does an LED work?

Light emitting diodes, commonly called LEDs, are found in all kinds of electronic devices. The LEDs are just tiny light bulbs. But unlike ordinary incandescent bulbs, they do not have a filament that will burn out. Further, they do not get hot during their use.

Light -emitting diodes are not made from silicon or germanium but are made by using elements like gallium, phosphorus and arsenic. By varying the quantities of these elements, it is possible to produce light of different wavelengths with colours that include red, green, yellow and blue. For example, when a LED is manufactured using gallium arsenide, it will produce a red light. If the LED is made with gallium phosphide, it will produce a green light.

Advantages and Applications of LEDs

Advantages, The light-emitting diode (LED) is a solid-state light source. LEDs have replaced incandescent lamps in many applications because they have the following advantages:

(i) Low voltage

(ii) Longer life (more than 20 years)

(iii) Fast on-off switching.