Luminescence is aspontaneous emission ofradiation from an electronically or vibrationally excited species not inthermal equilibrium with its environment.[1] A luminescent object emitscold light in contrast toincandescence, where an object only emits light after heating.[2] Generally, the emission of light is due to the movement of electrons between different energy levels within an atom after excitation by external factors. However, the exact mechanism of light emission in vibrationally excited species is unknown.
The dials, hands, scales, and signs of aviation and navigational instruments and markings are often coated with luminescent materials in a process known asluminising.[3]
Lyoluminescence, a result of dissolving a solid (usually heavily irradiated) in a liquid solvent
Candoluminescence, is light emitted by certain materials at elevated temperatures, which differs from theblackbody emission expected at the temperature in question.
Fluorescence, traditionally defined as the emission of light that ends immediately after the source of excitation is removed. As the definition does not fully describe the phenomenon, quantum mechanics is employed where it is defined as there is no change in spin multiplicity from the state of excitation to emission of light.[2]
Phosphorescence, traditionally defined as persistent emission of light after the end of excitation. As the definition does not fully describe the phenomenon, quantum mechanics is employed where it is defined as there is a change in spin multiplicity from the state of excitation to the emission of light.[2]
^Cooper, John R.; Randle, Keith; Sokhi, Ranjeet S. (2003).Radioactive Releases in the Environment: Impact and Assessment.Wiley. p. 192.ISBN978-0-471-89924-2.
^Piezoluminescence phenomenon N. A. Atari Physics Letters A Volume 90, Issues 1-2, 21 June 1982, Pages 93–96doi:10.1016/0375-9601(82)90060-3
^Sidran, Miriam (1968). "The Luminescence of the Moon". In Kopal, Zdeněk (ed.).Advances in Astronomy and Astrophysics (Volume 6). Academic Press. p. 301.
^"Über Fluorescenz und Phosphorescenz, I. Abhandlung" (On fluorescence and phosphorescence, first paper),Annalen der Physik und Chemie,34: 446–463. From page 447: "Ich möchte für diese zweite Art der Lichterregung, für die uns eine einheitliche Benennung fehlt, den Namen Luminescenz vorschlagen, und Körper, die in dieser Weise leuchten, luminescirende nennen." [For this second type of light excitation, for which we lack a consistent name, I would like to suggest the name of "luminescence", and call "luminescing" [any] bodies that glow in this way.]
