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Illuminance

In photometry, illuminance is the total luminous flux incident on a surface, per unit area. It is a measure of how much the incident light illuminates the surface, wavelength-weighted by the luminosity function to correlate with human brightness perception. Similarly, luminous emittance is the luminous flux per unit area emitted from a surface. Luminous…

Measurement, Overview & Relation to luminous intensity

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Common symbols
Ev
Dimension
L − 2 J {\displaystyle {\mathsf {L}}^{-2}{\mathsf {J}}}
In SI base units
cd·sr·m−2
Other units
phot, foot-candle
SI unit
lux

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Overview

Astronomy

Relation to luminous intensity

Relation to luminance

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Map overview Semantic statistics

Illuminance

Nodes34
Edges33
Triples28
Avg. degree1.94
Density0.058824
Components1

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Illuminance

Top relations

related to External links · 10
Illuminance → Also, Constants, Estimating Luminance, Illuminance Converter Archived, Illuminance QuantityKodak's, Library, LLC, PDF, Units, Wayback MachineKnowledgedoor
related to Astronomy · 5
Illuminance → Earth's, Ev, In, The, V-magnitudes
related to Relation to luminance · 4
Illuminance → Mv, Omega, Sigma, The
is a · 2
Illuminance → phot, total luminous flux incident on a surface
related to Relation to luminous intensity · 2
Illuminance → Iv, When
Common symbols · 1
Illuminance → Ev
Dimension · 1
Illuminance → L − 2 J {\displaystyle {\mathsf {L}}^{-2}{\mathsf {J}}}
In SI base units · 1
Illuminance → cd·sr·m−2
Other units · 1
Illuminance → phot, foot-candle
SI unit · 1
Illuminance → lux

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Important terminology

lux luminous unit surface brightness luminance per also light displaystyle units exitance used area lm phot foot-candle mathrm flux incident

Entity relationships Subject–Predicate–Object triples

SubjectPredicateObjectConfidenceSrc
IlluminanceCommon symbolsEv1.00infobox
IlluminanceDimensionL − 2 J {\displaystyle {\mathsf {L}}^{-2}{\mathsf {J}}}1.00infobox
IlluminanceIn SI base unitscd·sr·m−21.00infobox
IlluminanceOther unitsphot, foot-candle1.00infobox
IlluminanceSI unitlux1.00infobox
Illuminanceis atotal luminous flux incident on a surface0.90text
Illuminanceis aphot0.90text
Illuminancerelated to AstronomyIn0.60section
Illuminancerelated to AstronomyEarth's0.60section
Illuminancerelated to AstronomyThe0.60section
Illuminancerelated to AstronomyV-magnitudes0.60section
Illuminancerelated to AstronomyEv0.60section

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    Min side: 3
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