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The Dr. Bill FAQ

What Makes an LED Light Up?

Jim in Hayward asked this question, and Bill replied that it is difficult to explain without understanding solid-state physics.

He did explain that inside a Light Emitting Diode, when electrons move across a junction (the place where two different semi-conductors meet) inside the diode, they give up photons, thus producing light.

This page was last modified on Monday, 11-Oct-2004 20:04:21 PDT.


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