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Postby yolandy » Wed Dec 19, 2007 9:12 pm

Hello. This is Yolandy. This is my first time using this website. Thank you for having it open for me.

Will you please explain how LED lights work?

Thank you.
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Postby barretttomlinson » Thu Dec 20, 2007 1:25 am

Try searching Google for "how LEDs work". It will return several good explanations, one of which is:


Hope this helps.
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Postby Wen Phan » Fri Feb 08, 2008 1:45 am

LED stands for "light-emitting diode." A diode consists of two "special" materials that are "put" together. For a regular (non-light emitting diode), when a voltage is applied with one polarity, current flows. In the other polarity, current does not flow. For an LED, when you apply the right voltage polarity (also called a bias) such that current flows, some of the electrons that flow in the current "move" to a lower "energy state." When an electron moves to a lower energy state in an LED, it emits a photon, or light. The amount of energy level change (also called the bandgap energy) determines the color (frequency) of the light.

I hope this helps.

Wen Phan
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