WHAT IS LIGHT EMMITING DIODE ?

LED is a very commonly used device nowadays we use it in various application because of its small size and,cheap prize its very popular among peoples . we use it even in special television set for screen as LED pixels which is useful for clarity for distance audience . basically it is a diode which is set to be in forward condition .

 

Full form of LED is LIGHT EMITTING DIODE .

As evident from name it is diode who produce photon when voltage is given to it . this type of diode is not made by generally used semiconductor's like silicon and germanium it manufactured by arsenic phosphorus and gallium . various types of color can can be produced by changing quantities of material it made up of . 

WORKING -

Basically it is like a normal diode just difference with it produces light when a forward voltage applied to it . as we know  electron needs energy to jump from lower orbit to higher orbit ,  the working of LED is typically reverse of this process electron releases energy in the form of photon and heat when it fall from higher energy level to lower energy level .

 

So when we set up a forward voltage across the diode the electron present at the N type region flow toward P type region and combines with holes present at the P type region releasing energy in the form of photon and heat . 

This phenomenon is also known as electroluminescence 

PROS - 

1) Small in size hence light in weight .

2) Runs on low power .

3) Take's too little time to response .

4) Life span is comparatively very long with comparison of investment . 

CONS - 

1) Small change in voltage can damage system .

2) Not repairable if once it damaged .