luminance

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luminance

physics

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June 30, 2026

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Luminance refers to the brightness of a surface, essentially how much visible light it emits or reflects. It is measured in units like the lambert, which is defined as the brightness of a surface radiating one lumen per square centimeter. The intensity of light from a source is measured in candela, with one candela being equal to one lumen per steradian. Luminance is a key aspect of how we perceive the brightness of objects and is related to the overall quality of light.1234

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colour
Tristimulus measurement and chromaticity diagrams
…their different Y values (luminance, or visually perceived brightness).
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…their different Y values (luminance, or visually perceived brightness).
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television
Basic principles of compatible colour: The NTSC system
…by three quantities: (1) its luminance (brightness or “brilliance”); (2) its hue (the redness, orangeness, blueness, or greenness, etc., of the light); and (3) its saturation (vivid versus pastel quality). Since the intended luminance value of each point in the scanning pattern is transmitted by the methods of monochrome television,…
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…by three quantities: (1) its luminance (brightness or “brilliance”); (2) its hue (the redness, orangeness, blueness, or greenness, etc., of the light); and (3) its saturation (vivid versus pastel quality). Since the intended luminance value of each point in the scanning pattern is transmitted by the methods of monochrome television,…
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luminescence
Efficiency of luminescence; luminance
The efficiency of luminescence emission must be regarded on an energy and a quantum basis. When every exciting photon yields an emitted photon of the same energy (as is the case for resonance excitation—i.e., excitation of fluorescence by a monochromatic light of exactly the…
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The efficiency of luminescence emission must be regarded on an energy and a quantum basis. When every exciting photon yields an emitted photon of the same energy (as is the case for resonance excitation—i.e., excitation of fluorescence by a monochromatic light of exactly the…
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film
Luminosity
The intense brightness of the picture projected by powerful light onto a coated screen in itself transforms the most mundane element of reality. The appeal of a luminous picture is attested by efforts of advertisers to achieve luminous effects in posters and displays. The…
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The intense brightness of the picture projected by powerful light onto a coated screen in itself transforms the most mundane element of reality. The appeal of a luminous picture is attested by efforts of advertisers to achieve luminous effects in posters and displays. The…
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