English - English
Definition of footlambert in English English dictionary
- A unit of luminance (photometric brightness) equal to 1/pi candela per square foot, or to the uniform luminance of a perfectly diffusing surface emitting or reflecting light at the rate of one lumen per square foot, or to the average luminance of any surface emitting or reflecting light at that rate
- A unit of luminance or brightness equal to 1/d candles per foot'
- A unit of luminance (photometric brightness) equal to one candela per square foot
- A measurement of exitance, equal to lumens per square foot The use of this term is no longer popular; exitance should be used instead See exitance
- An older unit for luminance (brightness) that has been replaced by the "nit "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