Electroluminescence
Electroluminescence (EL) is an optical phenomenon and electrical phenomenon where a material emits light in response to an electric current passed through it, or to a strong electric field. This is distinct to light emission resulting from heat (incandescence) or from the action of chemicals (chemoluminescence).
Mechanism
Electroluminescence is the result of radiative recombination of electrons and holes in a material (usually a semiconductor). The excited electrons release their energy as photons - light. Prior to recombination, electrons and holes are separated either as a result of doping of the material to form a p-n junction (in semiconductor electroluminescent devices such as LEDs), or through excitation by impact of high-energy electrons accelerated by a strong electric field (as with the phosphors in electroluminescent displays).
Examples of electroluminescent materials
External links
- Overview of electroluminescent display technology, and the discovery of electroluminescence.
| Sources of light / lighting
|
| Natural/Prehistoric light sources: |
| bioluminescence (Fireflies, Foxfire, et cetera) | Celestial objects | Lightning |
| Combustion-based light sources: |
| Acetylene/Carbide lamps | Candle | Davy lamps | Fire | Gas lighting | Kerosene lamp | Limelight | Oil lamp | Rushlight |
| Nuclear/direct chemical light sources: |
| Betalights | Chemoluminescence/Lightsticks |
| Electric light sources: |
| Arc lamp | Incandescent | Fluorescent |
| High-intensity discharge: |
| HMI lamps | Mercury-vapor lamps | Metal halide lamps | Sodium vapor lamps | Xenon arc lamps |
| Other electric: |
| Electroluminescent (EL) lamps | Inductive lighting | LEDs | Neon and argon lamps | Sulfur lamp | Xenon flash lamps | Yablochkov candle |