Luminescence

Description

An emission of light from energy changes that do not involve heat. Some luminescent materials are called phosphors. When luminescent materials are activated by the absorption of light (i.e., photoluminescence), their electrons can move from the ground level to an elevated energy level. Later when the electron falls back to its original orbital, a photon of light is emitted. When the time difference between excitation and emission is less than 1/100,000 of a second, then the luminescence is called fluorescence. If the length of time is greater then the luminescence is called phosphorescence. Examples are light from the firefly, fluorescent lamp tubes, and television screens. Other types of luminescence include; bioluminescence, cathodoluminescence, chemoluminescence, crystalloluminescence, radioluminescence, thermoluminescence, and triboluminescence.

Synonyms and Related Terms

photoluminescence; fluorescence; phosphorescence; luminosity; bioluminescence; cathodoluminescence; chemiluminescence; crystalloluminescence; radioluminescence; thermoluminescence; triboluminescence; luminescens (Dan., Nor.); Lumineszenz (Deut.); luminescence (Fr.); luminescentie (Ned.); luminescencja (Pol.); luminiscens (Sven.); luminescência (Port.)

Authority

• Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993

• Wikipedia, the free encyclopedia, at http://www.wikipedia.com Comment: http://en.wikipedia.org/wiki/Luminescence

• Book and Paper Group, Paper Conservation Catalog, AIC, 1984, 1989

• Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997

• The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998

• Art and Architecture Thesaurus Online, http://www.getty.edu/research/tools/vocabulary/aat/, J. Paul Getty Trust, Los Angeles, 2000