The light emitting diode or LED as it is popularly known is a device which emits light when an electric current is applied across its terminals. When this LED is switched on electrons are able to recombine with holes, releasing energy in the form of photons
Light emitting diodes, also known as LED’s have changed the world of lighting. They not only have a long shelf life but are also environment friendly and require very little energy to work on. They are small and can fit into any electrical circuit.
LED’s are specially designed lighting instruments that are capable of emitting light of a certain wavelength. They can produce light of wavelength ranging from 400 to 650 nanometers depending on the color and intensity. They are usually built inside rounded plastic bulbs, which make the light look much brighter and concentrated. When a diode is forward biases, the electrons and the holes present in it move back and forth freely across the junction, collide, and combine with each other.
Over a period, the electrons present at the negative port starts moving towards the positive port where they combine with a hole and soon disappear. This leads to the formation of an atom, which is stable and gives off light in the form of a tiny packet or photon of light.
LED’s are an inexpensive form of light, which is small. They are easy to control electronically and come in a variety of colors. They produce light electronically, which makes them energy efficient as they do not get hot and use minimum electricity. LED’s can also be used for making invisible infrared light, which has found application in wide range of activities.
