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(General Physics) the luminous flux incident on unit area of a surface. It is measured in lux. Symbol: Ev Sometimes called: illumination Compare irradiance


(ɪˌlu məˈneɪ ʃən)

1. an act or instance of illuminating.
2. the state of being illuminated.
3. a decoration of lights.
4. Sometimes, illuminations. a display using lights as a major decoration.
5. intellectual or spiritual enlightenment.
6. the intensity of light falling at a given place on a lighted surface; the luminous flux incident per unit area, expressed in lumens per unit of area.
7. a supply of light.
8. decoration of a manuscript or book with a painted design in color and gold or silver.
9. a design used in such decoration.
[1300–50; Middle English < Latin]
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.illuminance - the luminous flux incident on a unit area
brightness level, luminance, luminosity, luminousness, brightness, light - the quality of being luminous; emitting or reflecting light; "its luminosity is measured relative to that of our sun"
References in periodicals archive ?
Power installations, main building distribution and subdistribution, lighting system, daylight and presence-dependent regulation of illuminance, emergency lighting as central battery system, exterior lighting, fault light floor protection device
Light state and indoor illuminance are being measured by standalone data loggers installed in each office.
This paper investigates to adequate the daylighting performance in terms of illuminance level (lux) and daylight factor (DF) in low cost high-rise residential building in tropical area.
Range of illuminance this been selected according to the IE SNA recommendations based on the type of activity [18], [7].
Layers of transparent hydrogel electrodes sandwich a ZnS phosphor-doped dielectric elastomer layer; creating thin rubber sheets that change illuminance and capacitance under deformation.
The BER performance with the SOP ER enhancement can satisfy FEC at low illuminance (i.
1-2016 energy code will use the performance data of LEDs, not fluorescents, to calculate illuminance levels.
Generally, a dimming system will save more energy than a switching system when illuminance is adjusted many times during the day due to climate conditions and variable illuminance needs.
illuminance uniformity, luminance distributions, light colour characteristics and glare.
Summary: installing the right tyPe of lighting, ensuring right illuminance and combining direct and indirect light source are very imPortant while designing offices as it Plays a very imPortant role in ensuring Productivity and health of emPloyees.
Ei is the illuminance due to daylight at a point on the indoors working plane
The zone has artificial lighting controls with a 500 lux illuminance set point facing the ceiling.