Definition of luminance in English:



mass nounPhysics
  • 1The intensity of light emitted from a surface per unit area in a given direction.

    • ‘Nits are also a measure of luminance, in so many candela per square metre.’
    • ‘This principal component direction is taken to be the luminance direction.’
    • ‘The specifications are commonly based on the 2 - D illuminance, luminance, intensity, chromaticity, and polarization distributions.’
    1. 1.1 The component of a television signal which carries information on the brightness of the image.
      • ‘These signals are also what is referred to as Y / C signal or luminance and chrominance.’
      • ‘The Y component is the luminance of the signal (not the color yellow), and delivers the gray scale image.’
      • ‘It is thus possible to quickly restore the light quantity control function by inputting the current luminance signal to an iris controller before the display of the still picture is stopped.’
      • ‘A sequence of passes separates the luminance and chrominance information from the composite video signal and demodulates the color carrier to separate out color information.’
      • ‘Note that the green channel has twice the number of photodetectors as red or blue (this is because the majority of luminance information is carried in the green channel).’


Late 19th century (as a general term meaning ‘light, brightness’): from Latin luminant- ‘illuminating’ (from the verb luminare) + -ance.