What is the difference between an LED and an LCDSolutionA li

What is the difference between an LED and an LCD?

Solution

A light emitting diode(LED) is a semiconductor device that emits visible light when an electric current passes through it. Basicly LED is a p-n junction deivce. Generally in any forward biased p-n junction diode, recombination of electrons and hole will occurs when we energize it. In this recombination the excess energy will be released in the form of heat in most of the materials. But materials like gallium arsenide phospide(GaAsP) and Gallium phospide(GaP), the released energy in the form of light. And this process is called as electroluminescence. LED\'s are having longer life.

Whereas liquid crystal display (LCD) is a material whose molecular structure will change whenever we applied some voltage across it. Indium oxide is an example for this type of material. When we apply the voltage across this mateiral molecular arrangement is distrubed, this will establish refraction phenomenon if we incident a light on this material. LCD requires a light source or LED\'s to use it as display. LCD requires low power compared to LED.