Noun
That property which some transparent bodies have of producing at their surface, or within their substance, light different in color from the mass of the material, as when green crystals of fluor spar afford blue reflections. It is due not to the difference in the color of a distinct surface layer, but to the power which the substance has of modifying the light incident upon it. The light emitted by fluorescent substances is in general of lower refrangibility than the incident light.
Source: Webster's dictionaryAccording to the belief, molecules closer together than 200 nanometers could not be told apart with focused light. This is because, in a packed molecular crowd, the molecules shout out their fluorescence simultaneously, causing their signal, their voices, to be confused. Stefan Hell
A fluorescence microscope is then used to detect fluorescently labeled antibodies bound to internalized antigens within clinical samples or cultured cells. Source: Internet
Analysis of this fluorescence allows monitoring interactions between Cm(III) ions in organic and inorganic complexes. Source: Internet
Another adaptive use of fluorescence is to generate red light from the ambient blue light of the photic zone to aid vision. Source: Internet
Another possibility is that the granules provide photoprotection: the bursts of AA fluorescence entail the conversion of damaging UV light to relatively harmless visible light. Source: Internet
A somewhat more reliable statement, although still with exceptions, would be that the fluorescence spectrum shows very little dependence on the wavelength of exciting radiation. Source: Internet