A luminescence emitted by certain substances due to the absorption of radiation at one wavelength, and the almost instantaneous re-emission of radiation at another, usually longer wavelength. The re-radiation stops almost as soon as the incident radiation is halted, thus distinguishing this phenomenon from phosphorescence, in which re-radiation of light may continue for some time after the incident radiation is halted.

"The color of the radiated light typically differs from the apparent color 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, by first absorbing the light to achieve an excited state, and then radiating light to resume the ground energy level. The light emitted by fluorescent substances is in general of longer wavelength than the incident light. The radiation can also be induced by ionizing radiation which is not electromagnetic, such as alpha or beta rays, and cathode rays. This property is possessed by fluorspar, uranium glass, sulphide of calcium, and many other substances. It finds use in analytical instruments to detect or measure radiation, and in some commercial applications." [1913 Webster]

top

OXFORD DICTIONARY

Fluorescence, n.
1 the visible or invisible radiation produced from certain substances as a result of incident radiation of a shorter wavelength as X-rays, ultraviolet light, etc.
2 the property of absorbing light of short (invisible) wavelength and emitting light of longer (visible) wavelength.

Etymology

FLUORSPAR (which fluoresces) after opalescence

top

THESAURUS

Fluorescence

autoluminescence, bioluminescence, cathode luminescence, chemicoluminescence, chemiluminescence, corposant, crystalloluminescence, double corposant, electroluminescence, fata morgana, fox fire, ignis fatuus, luciferase, luciferin, luminescence, luminophor, marshfire, noctiluscence, phosphor, phosphorescence, photoluminescence, radioluminescence, thermoluminescence, tribofluorescence, triboluminescence, tribophosphorescence, wisp, witch fire

top

ROGET THESAURUS

Fluorescence

Luminary

N luminary, light, flame, spark, scintilla, phosphorescence, fluorescence, sun, orb of day, Phoebus, Apollo, Aurora, star, orb, meteor, falling star, shooting star, blazing star, dog star, Sirius, canicula, Aldebaran, constellation, galaxy, zodiacal light, anthelion, day star, morning star, Lucifer, mock sun, parhelion, phosphor, phosphorus, sun dog, Venus, aurora, polar lights, northern lights, aurora borealis, southern lights, aurora australis, lightning, chain lightning, fork lightning, sheet lightning, summer lightning, ball lightning, kugelblitz, phosphorus, yellow phosphorus, scintillator, phosphor, firefly luminescence, ignis fatuus, Jack o'lantern, Friar's lantern, will-o'-the- wisp, firedrake, Fata Morgana, Saint Elmo's fire, glowworm, firefly, June bug, lightning bug, anglerfish, gas, gas light, lime light, lantern, lanthorn, dark lantern, bull's-eye, candle, bougie, taper, rushlight, oil, wick, burner, Argand, moderator, duplex, torch, flambeau, link, brand, gaselier, chandelier, electrolier, candelabrum, candelabra, girandole, sconce, luster, candlestick, lamp, light, incandescent lamp, tungsten bulb, light bulb, flashlight, torch, arc light, laser, maser neon bulb, neon sign, fluorescent lamp, filament, socket, contacts, filler gas, firework, fizgig, pyrotechnics, rocket, lighthouse, self-luminous, glowing, phosphoric, phosphorescent, fluorescent, incandescent, luminescent, chemiluminescent, radiant, blossomed the lovely stars, the forget-me-nots of the angels, the sentinel stars set their watch in the sky, the planets in their station list'ning stood, the Scriptures of the skies, that orbed continent, the fire that severs day from night.

Transparency

N transparence, transparency, clarity, translucence, translucency, diaphaneity, lucidity, pellucidity, limpidity, fluorescence, transillumination, translumination, transparent medium, glass, crystal, lymph, vitrite, water, transparent, pellucid, lucid, diaphanous, translucent, tralucent, relucent, limpid, clear, serene, crystalline, clear as crystal, vitreous, transpicuous, glassy, hyaline, hyaloid, vitreform.

For further exploring for "Fluorescence" in Webster Dictionary Online