n (1) Brightness is measured by the flux emitted per unit emissive area as projected on a plane normal to the line of sight. The unit of brightness is that of a perfectly diffusing surface giving out one lumen per square centimeter of projected surface and is called the lambert. The millilambert (0.001 lambert) is a more convenient unit. Candle per square centimeter is the brightness of a surface which has, ion the direction considered, a luminous intensity of one candle per cm2. (2) (Deprecated) The dimension of color that is referred to an achromatic scale, ranging from black to white, also called lightness or luminous reflectance or transmittance. Because of confusion with saturation, the use of this term should be discouraged. (McDonald (ed) (1997) Colour physics for industry, 2nd edn. Roderick, Society of Dyers and Colourists, West Yorkshire).