A unit of luminance or brightness equal to 1/d candles per foot'.
The measure of reflectance of a surface; the number of reflected footcandles from a surface, sometimes referred to as the brightness of a surface.
Lumen per square foot, if the light source has the features of lambert. Measuring unit for the luminance of cathode ray tubes or other extensive light source. Stands for the brightness which the screen reflects to the audience. More exact measuring unit than ANSI lumen, if the room is not completely dark, since the remaining light changes the reflected image.
Measurement for the amount of light reflected which is described as the uniform lighting of a perfectly diffusing surface that reflects light at the rate of one Lumen per square foot. The number of footlamberts is measured by counting the number of foot-candles that reach the surface and by multiplying this figure by the amount of light reflecting on the surface.
old unit of luminance. 1fL = 3.426 candela per square meter
a luminance measurement unit
An obsolete term referring to a luminance of 1/? candelas per square foot.
A unit of luminance equal to 1/candela per square foot or to the uniform luminance at a perfectly diffusing surface emitting or reflecting light at the rate of one lumen per square foot. A lumen per square foot is a unit of incident light and a footlambert is a unit of emitted or reflected light. For a perfectly reflecting and perfectly diffusing surface, the number of lumens per square foot is equal to the number of footlamberts.
English unit of luminance. One footlambert is equal to 1/p candelas per square foot.
US luminance measurement unit (1 footlambert = 3.425 candelas per square meter). See Candela.
An older unit for luminance (brightness) that has been replaced by the "nit."
A unit of luminance equal to 0.3183010 candela per square foot, or to the uniform luminance of a perfectly diffusing surface emitting or reflecting light at a rate of one lumen per square foot, or to the average luminance of a surface emitting or reflecting light at that rate. An unobstructed sky of one footlambert uniform luminance contributes one footcandle of illuminance on a horizontal plane.
A unit of luminance (or brightness) equal to 1/π candles ft−2. In the United Kingdom this is also called the equivalent foot-candle.
