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n. Abbr. fL
A unit of luminance equal to 1/π candela per square foot.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Units) a former unit of luminance equal to the luminance of a surface emitting or reflecting 1 lumen per square foot. A completely reflecting surface illuminated by 1 foot-candle has a luminance of 1 foot-lambert. Abbreviation: ft-L
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


a unit of luminance equal to the luminance of a surface emitting a luminous flux of one lumen per square foot.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.foot-lambert - a former luminance unit equal to one lumen per square foot
luminance unit - a measure of luminance
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
References in periodicals archive ?
Calibration units include nit (cd/[m.sup.2]), lumens, lux, cd and foot-lamberts. All products feature NIST traceable calibration, carried out in Gamma's ISO 17025 NVLAP accredited laboratory.
The GSX theater system at the Peoria Riverfront Museum will deliver up to 6 foot-lamberts (ftL.) of brightness in Giant Screen 3D mode in 4:3 aspect ratio; a 3D image at least twice as bright when compared to alternative Giant Screen Cinema systems.