What (who) is luminescence - definition

EMISSION OF LIGHT BY A SUBSTANCE NOT RESULTING FROM HEAT

Luminescent; Luminesces; Luminescent measurements; Luminise; Luminising; Luminiscent microsphere; Light-emitting material; Light-emitting materials; Luminescent microsphere

luminescence

Luminescence is a soft, glowing light. (LITERARY)

Lights reflected off dust-covered walls creating a ghostly luminescence.

N-UNCOUNT

Luminescence

·add. ·noun The light thus produced; luminosity; phosphorescence.

II. Luminescence ·add. ·noun The faculty or power of voluntarily producing light, as in the firefly and glowworm.

III. Luminescence ·add. ·noun Any emission of light not ascribable directly to incandescence, and therefore occurring at low temperatures, as in phosphorescence and fluorescence or other luminous radiation resulting from vital processes, chemical action, friction, solution, or the influence of light or of ultraviolet or cathode rays, ·etc.

luminescence

[?lu:m?'n?s(?)ns]

¦ noun the emission of light by a substance that has not been heated, as in fluorescence and phosphorescence.

Derivatives

luminescent adjective

Origin

C19: from L. lumen, lumin- 'light' + -escence (denoting a state).

Wikipedia

Luminescence

Luminescence is the "spontaneous emission of radiation from an electronically excited species (or from a vibrationally excited species) not in thermal equilibrium with its environment", according to IUPAC definition. A luminescent object is emitting "cold light", in contrast to "incandescence", where an object only emits light after heating. Generally, 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, as seen in sonoluminescence.

There are various ways to make an object emit light, such as by light (photoluminescence), chemical reactions (chemiluminescence), electrical energy (electroluminescence), ultrasound vibrations (sonoluminescence), and by ionising radiation (radioluminescence).

The dials, hands, scales, and signs of aviation and navigational instruments and markings are often coated with luminescent materials in a process known as "luminising".

https://en.wikipedia.org/wiki/Luminescence

Pronunciation examples for luminescence

1. the Earth's luminescence will start

Dr. Christopher Mason _ The Next 500 Years _ Talks at Google

2. curbing their luminescence to firefly glimmers trapped

Knights Of The Borrowed Dark _ Dave Rudden _ Talks at Google

3. Ambient luminescence is something very different.

ted-talks_1098_RogierVanDerHeide_2010X-320k

4. That sparkle you're seeing is not luminescence,

ted-talks_833_EdithWidder_2010Z-320k

5. You don't see luminescence until the submersible

ted-talks_833_EdithWidder_2010Z-320k

Examples of use of luminescence

1. Dating techniques included radiocarbon dating and optical stimulated luminescence.

2. Although it seemed no more than a blink of the eye since Roger Federer trudged dejectedly off the Philippe Chatrier court two weeks ago having lost the French Open final to the Spaniard Rafael Nadal, he reappeared on his favourite Centre Court yesterday as if surrounded by an ethereal luminescence.