Irradiance

prefLabel
  • Irradiance
definition
  • Irradiance - A radiometric term for the power of electromagnetic radiation at a surface, per unit area. "Irradiance" is used when the electromagnetic radiation is incident on the surface. Irradiance data may be reported in any units (i.e. counts/s) due to, for example, being at a particular wavelength, or to being a not-fully-calibrated relative measurement.
topConceptOf
inScheme
Abstract from DBPedia
    In radiometry, irradiance is the radiant flux received by a surface per unit area. The SI unit of irradiance is the watt per square metre (W⋅m−2). The CGS unit erg per square centimetre per second (erg⋅cm−2⋅s−1) is often used in astronomy. Irradiance is often called intensity, but this term is avoided in radiometry where such usage leads to confusion with radiant intensity. In astrophysics, irradiance is called radiant flux. Spectral irradiance is the irradiance of a surface per unit frequency or wavelength, depending on whether the spectrum is taken as a function of frequency or of wavelength. The two forms have different dimensions and units: spectral irradiance of a frequency spectrum is measured in watts per square metre per hertz (W⋅m−2⋅Hz−1), while spectral irradiance of a wavelength spectrum is measured in watts per square metre per metre (W⋅m−3), or more commonly watts per square metre per nanometre (W⋅m−2⋅nm−1).

    放射照度(ほうしゃしょうど、英語: irradiance)とは、物体へ時間あたりに照射される、面積あたりの放射エネルギーを表す物理量である。放射束を物体の表面積で微分することにより得られる。SIにおける単位はワット毎平方メートル(記号: W m−2)が用いられる。天文学ではCGS単位系のエルグ毎平方センチメートル毎秒(記号: erg cm−2 s−2)がよく用いられる。 放射発散度は同じ単位を持つが、放射発散度は放射源の指標であり、放射照度は照射される対象の指標である。

    (Source: http://dbpedia.org/resource/Irradiance)