Question
Explain the working of LED.
✓
Answer
Working of LED:
- When the LED is forward biased, electrons from the semiconductor's conduction band recombine with holes from the valence band releasing sufficient energy to produce photons that emit monochromatic light.
- Because of the thin layer, a reasonable number of these photons can leave the junction and emit coloured light.
- The amount of light output is directly proportional to the forward current. Thus, the higher the forward current, the higher is the light output.
- The given figure schematically shows the emission of light when the electron-hole pair combines.
Working of LED
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