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irradiance

irradiance

3 8.5
The amount of light that falls on a surface
  • noun
  • /ɪˈreɪdiəns/
  • Specialized
translation icon : irradiancia
  • Our functional and morphological results indicate that the wavelength and the SPD, rather than total light irradiance, are crucial risk factors that contribute to photochemical retinal injury.
  • solar irradiance
  • irradiance levels
  • variations in irradiance

Examples

  • The beam of light incident on the objective lens usually has a Gaussian electric field (or irradiance) profile.

    Academic text (1996)
  • At the mid-latitudes, the daily solar irradiance follows a near-perfect sinusoidal pattern for the yearly cycle.

    Blog text (27)
  • And it's intuitive that the image irradiance goes as the inverse square of the F stop.

  • The peak in March tends to morph with the irradiance peak due to the orbital factor in January.

    Blog text (28)
  • Effectively, variations in growth irradiance are comparable to variations in inorganic carbon supply.

    Academic text (1993)
  • When these weighting factors are combined with the measured spectral irradiance of the source, an effective irradiance is determined.

    Academic text (1998)
  • We present evidence for long-term drift in solar UV irradiance, which is not found in its commonly used proxies.

    Blog text (29)
  • The differences between the irradiances from a fully clouded sky and a clear sky can be used to quantify the clouds' opposing effects.

    Academic text (2012)
  • At perihelion, the maximum available irradiance is 717 W/m², while at aphelion the maximum is 493 W/m².

    Blog text (27)
  • The solar panel's efficiency depends on the level of irradiance it receives during the day.

Synonyms

illumination
vsirradiance
12 4.1

The amount of light in a place or on a surface

is a technical measure per surface area rather than general visibility
illuminance
vsirradiance
  • Specialized
8.8

The amount of light that falls on a surface

measures light energy per surface area rather than luminous flux

How Bright

glare
37 3.3
brightness
41 1.0
irradiance
  • Specialized
3 8.5
dimness
4 3.4
darkness
534 1.0

Surface Forms

irradiance singular
irradiances plural

Morphology

irradiance = irradiate (semi-transparent) = ir + radiate + ance

The noun is a regular nominalization of 'irradiate' with '-ance', but 'irradiate' itself involves the prefix 'ir-' (not a negation) on 'radiate' and the term is technical.

Etymology

Irradiance comes from Latin parts in- 'on' and radiare 'to shine' and shares the same root as radiate and the English word 'ray'. So irradiance means how much light is shining on or falling onto a surface.