出典:Wiktionary
foot-lambert (複数形 foot-lamberts)
出典:Wikipedia
出典:『Wikipedia』 (2011/06/29 00:10 UTC 版)
A foot-lambert or footlambert (fL, sometimes fl or ft-L) is a unit of luminance in U.S. customary units and some other unit systems. A foot-lambert equals 1/π candela per square foot, or 3.426 candela per square meter (the corresponding SI unit). The foot-lambert is named after Johann Heinrich Lambert (1728–1777), a German mathematician, physicist and astronomer. It is rarely used by electrical and lighting engineers, in favor of the candela per square foot or candela per square meter.