The lambert (symbol L[1][2]) is a non-SI metric unit of luminance named for Johann Heinrich Lambert (1728–1777), a Swiss mathematician, physicist and astronomer.
A related unit of luminance, the foot-lambert, is used in the lighting, cinema and flight simulation industries.
The SI unit is the candela per square metre (cd/m2).
candela per square centimetre (0.3183 cd/cm2) or
cd m−2 Other units of luminance: