|1.||a state or quality of radiating or reflecting light|
|2.||L a measure (in candelas per square metre) of the brightness of a point on a surface that is radiating or reflecting light. It is the luminous intensity in a given direction of a small element of surface area divided by the orthogonal projection of this area onto a plane at right angles to the direction|
|[C19: from Latin lūmen light]|
|luminance (l'mə-nəns) Pronunciation Key
The luminous intensity of a light source per unit area. Occasionally the lambert unit is used to measure luminance. Also called photometric brightness.