luminance

American  

[loo-muh-nuhns] / ˈlu mə nəns /

noun

1. the state or quality of being luminous.

2. Also called luminosity.  the quality or condition of radiating or reflecting light.

   the blinding luminance of the sun.

3. Optics. the quantitative measure of brightness of a light source or an illuminated surface, equal to luminous flux per unit solid angle emitted per unit projected area of the source or surface.

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luminance British  

/ ˈluːmɪnəns /

noun

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

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luminance Scientific  

/ lo̅o̅′mə-nəns /

1. The luminous intensity of a light source per unit area. Occasionally the lambert unit is used to measure luminance.

2. Also called photometric brightness

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Etymology

Origin of luminance

1875–80; < Latin lūmin- (stem of lūmen ) light + -ance