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- Dictionaryluminesce/ˌluːmɪˈnɛs/
verb
- 1. emit light by luminescence: "genes in these marine bacteria make them luminesce"
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LUMINESCE definition: 1. (of a substance) to produce light without being heated: 2. (of a substance) to produce light…. Learn more.
- English (US)
LUMINESCE meaning: 1. (of a substance) to produce light...
- Znaczenie Luminesce, Definicja W Cambridge English Dictionary
LUMINESCE definicja: 1. (of a substance) to produce light...
- Simplified
LUMINESCE translate: （物质）发冷光. Learn more in the Cambridge...
- Translate to Traditional Chinese
LUMINESCE translate: （物質）發冷光的. Learn more in the Cambridge...
- Translate English to Portuguese
LUMINESCE translate: apresentar luminescência. Learn more in...
- Pronunciation in English
luminesce pronunciation. How to say luminesce. Listen to the...
- English
the giving out of light by a substance that has not been...
- English (US)
verb. lu· mi· nesce ˌlü-mə-ˈnes. luminesced; luminescing. Synonyms of luminesce. intransitive verb. : to exhibit luminescence. Examples of luminesce in a Sentence. Recent Examples on the Web. These examples are automatically compiled from online sources to illustrate current usage.
- Overview
- Sources and process
- Luminescence and incandescence
- Luminescent pigments and dyes
- Early investigations
- Phosphorescence and fluorescence
- GeneratedCaptionsTabForHeroSec
luminescence, emission of light by certain materials when they are relatively cool. It is in contrast to light emitted from incandescent bodies, such as burning wood or coal, molten iron, and wire heated by an electric current. Luminescence may be seen in neon and fluorescent lamps; television, radar, and X-ray fluoroscope screens; organic substanc...
Luminescence emission occurs after an appropriate material has absorbed energy from a source such as ultraviolet or X-ray radiation, electron beams, chemical reactions, and so on. The energy lifts the atoms of the material into an excited state, and then, because excited states are unstable, the material undergoes another transition, back to its un...
As mentioned above, luminescence is characterized by electrons undergoing transitions from excited quantum states. The excitation of the luminescent electrons is not connected with appreciable agitations of the atoms that the electrons belong to. When hot materials become luminous and radiate light, a process called incandescence, the atoms of the ...
Nonluminescent pigments and dyes exhibit colours because they absorb white light and reflect that part of the spectrum that is complementary to the absorbed light. A small fraction of the absorbed light is transformed into heat, but no appreciable radiation is produced. If, however, an appropriate luminescent pigment absorbs daylight in a special region of its spectrum, it can emit light of a colour different from that of the reflected light. This is the result of electronic processes within the molecule of the dye or pigment by which even ultraviolet light can be transformed to visible—e.g., blue—light. These pigments are used in such diverse ways as in outdoor advertising, blacklight displays, and laundering: in the latter case, a residue of the “brightener” is left in the cloth, not only to reflect white light but also to convert ultraviolet light into blue light, thus offsetting any yellowness and reinforcing the white appearance.
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Although lightning, the aurora borealis, and the dim light of glowworms and of fungi have always been known to mankind, the first investigations (1603) of luminescence began with a synthetic material, when Vincenzo Cascariolo, an alchemist and cobbler in Bologna, Italy, heated a mixture of barium sulfate (in the form of barite, heavy spar) and coal; the powder obtained after cooling exhibited a bluish glow at night, and Cascariolo observed that this glow could be restored by exposure of the powder to sunlight. The name lapis solaris, or “sunstone,” was given to the material because alchemists at first hoped it would transform baser metals into gold, the symbol for gold being the Sun. The pronounced afterglow aroused the interest of many learned men of that period, who gave the material other names, including phosphorus, meaning “light bearer,” which thereafter was applied to any material that glowed in the dark.
Today, the name phosphorus is used for the chemical element only, whereas certain microcrystalline luminescent materials are called phosphors. Cascariolo’s phosphor evidently was a barium sulfide; the first commercially available phosphor (1870) was “Balmain’s paint,” a calcium sulfide preparation. In 1866 the first stable zinc sulfide phosphor was described. It is one of the most important phosphors in modern technology.
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One of the first scientific investigations of the luminescence exhibited by rotting wood or flesh and by glowworms, known from antiquity, was performed in 1672 by Robert Boyle, an English scientist, who, although not aware of the biochemical origin of that light, nevertheless established some of the basic properties of bioluminescent systems: that the light is cold; that it can be inhibited by chemical agents such as alcohol, hydrochloric acid, and ammonia; and that the light emission is dependent on air (as later established, on oxygen).
In 1885–87 it was observed that crude extracts prepared from West Indian fireflies (Pyrophorus) and from the boring clam, Pholas, gave a light-emitting reaction when mixed together. One of the preparations was a cold-water extract containing a compound relatively unstable to heat, luciferase; the other was a hot-water extract containing a relatively heat-stable compound, luciferin. The luminescent reaction that occurred when solutions of luciferase and luciferin were mixed at room temperature suggested that all bioluminescent reactions are “luciferin–luciferase reactions.” In view of the complex nature of bioluminescent reactions, it is not astonishing that this simple concept of bioluminescence has had to be modified. Only a small number of bioluminescent systems have been investigated for their respective luciferin and the corresponding luciferase, the best known being the bioluminescence of fireflies from the United States, a little crustacean living in the Japanese sea (Cypridina hilgendorfii), and decaying fish and flesh (bacterial bioluminescence). Although bioluminescent systems have not yet found practical applications, they are interesting because of their high luminescence efficiency.
The name luminescence has been accepted for all light phenomena not caused solely by a rise of temperature, but the distinction between the terms phosphorescence and fluorescence is still open to discussion. With respect to organic molecules, the term phosphorescence means light emission caused by electronic transitions between levels of different multiplicity (explained more fully below), whereas the term fluorescence is used for light emission connected with electronic transitions between levels of like multiplicity. The situation is far more complicated in the case of inorganic phosphors.
The term phosphorescence was first used to describe the persistent luminescence (afterglow) of phosphors. The mechanism described above for the phosphorescence of excited organic molecules fits this picture in that it is also responsible for light persistence up to several seconds. Fluorescence, on the other hand, is an almost instantaneous effect, ending within about 10−8 second after excitation. The term fluorescence was coined in 1852, when it was experimentally demonstrated that certain substances absorb light of a narrow spectral region (e.g., blue light) and instantaneously emit light in another spectral region not present in the incident light (e.g., yellow light) and that this emission ceases at once when the irradiation of the material comes to an end. The name fluorescence was derived from the mineral fluorspar, which exhibits a violet, short-duration luminescence on irradiation by ultraviolet light.
Luminescence is the emission of light by certain materials when they are relatively cool, in contrast to incandescence. Learn about the sources, processes, and applications of luminescence, as well as its history and types, such as fluorescence, phosphorescence, and chemiluminescence.
- Karl-Dietrich Gundermann
Luminesce means to produce light without being heated, or to produce light by chemical reaction. Learn how to use this word in sentences and see translations in different languages.
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To luminesce is to shine or glow with light. Some types of jellyfish have the uncanny ability to luminesce underwater. Glow-in-the-dark paint will luminesce when you turn out the lights, and fireflies luminesce in the night sky during the summertime.
Luminescence is the giving out of light by a substance that has not been heated, or soft light. Learn more about the word, its usage, and related terms with examples from the Cambridge Dictionary and Corpus.
Luminesce means to exhibit luminescence, which is the property of giving off light without heat. Learn the word origin, pronunciation, synonyms, and usage examples of luminesce from Collins English Dictionary.
