luminance

[ loo-muh-nuhns ]

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.

luminance

/ ˈluːmɪnəns /

noun

1. a state or quality of radiating or reflecting light
2. 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 L

luminance

/ 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

Word History and Origins

Origin of luminance¹

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

Word History and Origins

Origin of luminance¹

C19: from Latin lūmen light

Example Sentences

The Perseid meteor shower is back for its annual display, dotting our skies with its signature bright, streaking trails at peak luminance.

From Salon

Early in life, when newborns receive strongly limited color information, the brain is forced to learn to distinguish objects based on their luminance, or intensity of light they emit, rather than their color.

From Science Daily

Conventional blue OLEDs typically require around 4 V for a luminance of 100 cd/m2; this is higher than the industrial target of 3.7 V -- the voltage of lithium-ion batteries commonly used in smartphones.

From Science Daily

But at dawn and dusk, when males of the species swoop and dart in the pale luminance to attract a mate, they really shine.

From Science Magazine

In their quiet luminance, the scars left from the Rupture almost disappeared.

From Literature