Science & TechHow it works

How an LED glows without getting hot.

An incandescent bulb heats a tungsten wire to about 2,500 °C; only around 5 % of the energy becomes light, the rest is heat. In an LED, electrons meet electron holes at a semiconductor junction and release energy directly as photons. White LED light usually comes from a blue LED plus yellow phosphor. LEDs need about 80 % less electricity for the same brightness.

Useful: Shop by lumens, not watts: 800 lumens is roughly an old 60-watt bulb.

Source: en.wikipedia.org

Alltag Energie Technik

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