- Explain briefly the process of emission of light by a Light Emitting Diode (LED).
- Which semiconductors are preferred to make LEDs and why?
- Give two advantages of using LEDs over conventional incandescent lamps.
CBSE OUTSIDE DELHI - SET 1 SOUTH 2016
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- During Forward bias of LED, electrons move from n side to p side and holes move from p side to n side. During recombination, energy is released in the form of photons having energy hv of the order of band gap.
- Ga As/Ga As P.
- Low operational voltage, fast action, no warm up time required, nearly monochromatic, long life, ruggedness, fast on and off switching capacity.
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