Luminescence
Luminescence is
light not generated by high temperatures alone.
It is different from
incandescence, in that it usually occurs at low temperatures. Examples include
fluorescence,
bioluminescence and
phosphorescence.
Luminescence can be caused by chemical or biochemical changes, electrical energy, subatomic motions, reactions in crystals, or stimulation of an atomic system.
The process of coating dials, hands, scales and signs on, particularly, aviation and navigational instruments and markings with luminescent materials is known as
luminising.
The following kinds of luminescence are known to exist:
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Chemoluminescence (including
Bioluminescence)
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Crystalloluminescence*
Electroluminescence**
Cathodoluminescence*
Photoluminescence**
Phosphorescence**
Fluorescence *
Radioluminescence*
Sonoluminescence*
Thermoluminescence*
TriboluminescenceHistorically,
radioactivity was first thought of as a form of "radioluminescence", although it is today considered to be separate since it involves more than electromagnetic radiation.
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Luminescence on Scienceworld