Everyday Science · 45 sec
Light-emitting diode
The science behind something you encounter, use, or wonder about.
The useful idea
- The useful idea
A light-emitting diode (LED) is an electronic component that uses a semiconductor to emit light when current flows through it.
- How it works
Electrons in the semiconductor recombine with electron holes, thereby releasing energy in the form of photons.
- Why it matters
The color of the light (corresponding to the energy of the photons) is determined by the energy required for electrons to cross the band gap of the semiconductor.
Why this matters
Look for Light-emitting diode the next time you notice this pattern in everyday life.
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Look for Light-emitting diode the next time you notice this pattern in everyday life.
Test your recall
Which idea belongs to the explanation of Light-emitting diode?
- The useful idea — correct
- How it works
- Why it matters
A light-emitting diode (LED) is an electronic component that uses a semiconductor to emit light when current flows through it.