Semiconductors/LED

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LED: The low cost and low energy consuming lights[edit | edit source]

LED stands for Light emitting diode An LED is a device which converts electrical energy into Radiation energy .An LED is a special type pn junction diode .The p side of the diode is connected to +ve terminal and n side to -ve terminal so that the p-n junction is forward biased. Schematic of a typical LED is show in figure.

How LED works or science of LEDs[edit | edit source]

When the junction is forward biased then movement of majority charge cariers takes place; electron of the n side flows to p-side and holes of p-side flows to n-side and after this holes and electrons combine together to maintain equilibrium .During the combination of electrons and holes some energy is released in the form of em waves. These em waves are generally lights. When the intensity of current is increased then the intensity of light increases, but after some limit intensity of light starts decreasing hence the LED is biased such that the intensity of light is maximum .

This is the science behind LEDs which are found in nearly all electronics devices used.

Advantage of LEDs[edit | edit source]

(1)The efficiency of these lamps is greatest, because it requires a little bit of electricity.

(2)The bandwidth of the light of the LEDs is very low hence it emits light of

(3)The amount of the heat energy in LEDs are negligible hence it emits cool light .It also prevents our ecosystem because it has a very less effect on it

In all ways LEDs are eco friendly, low cost and energy efficient Lamps