Definition - What does Electroluminescence (EL) mean?
Electroluminescence is a phenomenon of certain materials such as semiconductors that causes the material to emit light due to a strong electric field or passage of an electric current. Many applications such as automobile dashboard displays and nightlights are based on the principle of electroluminescence.
Techopedia explains Electroluminescence (EL)
The phenomenon of electroluminescence can be considered as both electrical and optical in nature. It occurs due to radiative recombination of holes and electrons of the concerned material. Photons are released by excited electrons, which results in light. Unlike incandescence (light generation due to heat), chemiluminescence (light generation due to chemical reaction), mechanoluminescence (light generation due to mechanical action) and sonoluminescence (light generation due to sound), electroluminescence is one rare instance in which direct conversion of electric energy to light occurs without generation of heat. Electroluminescence in crystals can be achieved mainly in two ways: intrinsically and charge injection. The two techniques differs in two ways with no net current passing through the electroluminescent material in the first case, and in the second, luminescence only lasts until the passage of the electric current.
An electroluminescent device is similar to a laser in the fact that photons are produced by the material when there is a change from a ground state to an excited state. The difference between an electroluminescent device and a laser lies in the fact that less energy is required to operate an electroluminescent device, and it also does not provide coherent light.