| The low-temperature emission of light as by a chemical or physiological process by a substance other than as a result of incandescence.
Meaning they emit and transmit photons, the basic particle of light. In a broader sense luminescent describes all minerals capable of giving off light when put under certain conditions. Three minerals that exhibit these characteristics are fluorescence, triboluminescence, and thermoluminescence.
Some studies are revealing an ability to use photons and light produced by luminescence as a key to the development of photonic computers and there is a related field of the phenomenon of bioluminescence, the production light by biological organisms. The firefly is probably the most well known example.
In industry this glow-in-the-dark technology is used from everything to light cockpits of aircraft, digital watches, to the revealing of fingerprints or blood products at crime scenes.
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