View source for Template:SI radiometry units

{{anchor|table-si-radiometry-units}}
{|class="wikitable" style="margin: 1em auto 1em auto"
|+ {{navbar-header |1={{resize|130%|{{#if:{{{1|}}}|Table&nbsp;{{{1}}}.&nbsp;}}SI radiometry units}}|2=SI radiometry units}}
|-
! colspan="2" | Quantity
! colspan="2" | Unit
! Dimension
! rowspan="2" | Notes
|-
! <small>Name</small>
! <small>Symbol</small>{{#tag:ref|[[Engineering:Standards organization|Standards organization]]s recommend that radiometric [[Physics:Physical quantity|quantities]] should be denoted with suffix "e" (for "energetic") to avoid confusion with photometric or [[Physics:Photon|photon]] quantities.|group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-e}}<!-- f.e. USA Standard Letter Symbols for Illuminating Engineering USAS Z7.1-1967, Y10.18-1967 -->
! scope="col" style="width: 10em;"|<small>Name</small>
! <small>Symbol</small>
! <small>Symbol</small>
|-
| [[Physics:Radiant energy|Radiant energy]]
| ''Q''<sub>e</sub>{{#tag:ref|Alternative symbols sometimes seen: ''W'' or ''E'' for radiant energy, ''P'' or ''F'' for radiant flux, ''I'' for irradiance, ''W'' for radiant&nbsp;exitance.|group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-alternative-symbol-radiometric}}<!-- radiant energy alternatives: Q is used in radiometry and photometry. Palmer recommends W (typo for E?) as acceptable alternative, but it conflicts with the alternative usage of W for radiant exitance by others. E is sometimes used in more general physics, but conflicts with the radiometric usage of E for irradiance. -->
| [[Joule|joule]]
| [[Joule|J]]
| '''M'''⋅'''L'''<sup>2</sup>⋅'''T'''<sup>−2</sup>
| Energy of electromagnetic radiation.
|-
| style=white-space:nowrap | [[Physics:Radiant energy density|Radiant energy density]]
| ''w''<sub>e</sub>
| joule per cubic metre
| J/m<sup>3</sup>
| '''M'''⋅'''L'''<sup>−1</sup>⋅'''T'''<sup>−2</sup>
| Radiant energy per unit volume.
|-
| [[Physics:Radiant flux|Radiant flux]]
| Φ<sub>e</sub>{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-alternative-symbol-radiometric}}<!-- radiant flux alternatives: Palmer uses uppercase Greek Phi, but recommends P as acceptable alternative, while he himself uses F in some HTML documents. P was also found to be used in Slovakian WP. -->
| [[Watt|watt]]
| [[Watt|W]] = J/s
| '''M'''⋅'''L'''<sup>2</sup>⋅'''T'''<sup>−3</sup>
| Radiant energy emitted, reflected, transmitted or received, per unit time. This is sometimes also called "radiant power".
|-
| rowspan=2 | [[Physics:Radiant flux|Spectral flux]]
| Φ<sub>e,ν</sub>{{#tag:ref|Spectral quantities given per unit [[Physics:Frequency|frequency]] are denoted with suffix "[[Nu (letter)|ν]]" (Greek)—not to be confused with suffix "v" (for "visual") indicating a photometric quantity.|group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-nu}}
| watt per [[Hertz|hertz]]
| W/[[Hertz|Hz]]
| '''M'''⋅'''L'''<sup>2</sup>⋅'''T'''<sup>−2</sup>
| rowspan=2 | Radiant flux per unit frequency or wavelength. The latter is commonly measured in W⋅nm<sup>−1</sup>.
|-
| Φ<sub>e,λ</sub>{{#tag:ref|Spectral quantities given per unit [[Physics:Wavelength|wavelength]] are denoted with suffix "[[Lambda|λ]]" (Greek).|group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-lambda}}
| watt per metre
| W/m
| '''M'''⋅'''L'''⋅'''T'''<sup>−3</sup>
|-
| [[Physics:Radiant intensity|Radiant intensity]]
| ''I''<sub>e,Ω</sub>{{#tag:ref|Directional quantities are denoted with suffix "[[Omega|Ω]]" (Greek).|group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-omega}}<!-- Notations recommended by ISO 9288 (1989). -->
| watt per [[Steradian|steradian]]
| W/[[Steradian|sr]]
| '''M'''⋅'''L'''<sup>2</sup>⋅'''T'''<sup>−3</sup>
| Radiant flux emitted, reflected, transmitted or received, per unit solid angle. This is a ''directional'' quantity.
|-
| rowspan=2 | [[Physics:Radiant intensity|Spectral intensity]]
| ''I''<sub>e,Ω,ν</sub>{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-nu}}
| watt per steradian per hertz
| W⋅sr<sup>−1</sup>⋅Hz<sup>−1</sup>
| '''M'''⋅'''L'''<sup>2</sup>⋅'''T'''<sup>−2</sup>
| rowspan=2 | Radiant intensity per unit frequency or wavelength. The latter is commonly measured in W⋅sr<sup>−1</sup>⋅nm<sup>−1</sup>. This is a ''directional'' quantity.
|-
| ''I''<sub>e,Ω,λ</sub>{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-lambda}}
| watt per steradian per metre
| W⋅sr<sup>−1</sup>⋅m<sup>−1</sup>
| '''M'''⋅'''L'''⋅'''T'''<sup>−3</sup>
|-
| [[Physics:Radiance|Radiance]]
| ''L''<sub>e,Ω</sub>{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-omega}}
| watt per steradian per square metre
| W⋅sr<sup>−1</sup>⋅m<sup>−2</sup>
| '''M'''⋅'''T'''<sup>−3</sup>
| Radiant flux emitted, reflected, transmitted or received by a ''surface'', per unit solid angle per unit projected area. This is a ''directional'' quantity. This is sometimes also confusingly called "intensity".
|-
| rowspan=2 | [[Physics:Radiance|Spectral radiance]]
| ''L''<sub>e,Ω,ν</sub>{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-nu}}
| watt per steradian per square metre per hertz
| W⋅sr<sup>−1</sup>⋅m<sup>−2</sup>⋅Hz<sup>−1</sup>
| '''M'''⋅'''T'''<sup>−2</sup>
| rowspan=2 | Radiance of a ''surface'' per unit frequency or wavelength. The latter is commonly measured in W⋅sr<sup>−1</sup>⋅m<sup>−2</sup>⋅nm<sup>−1</sup>. This is a ''directional'' quantity. This is sometimes also confusingly called "spectral intensity".
|-
| ''L''<sub>e,Ω,λ</sub>{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-lambda}}
| watt per steradian per square metre, per metre
| W⋅sr<sup>−1</sup>⋅m<sup>−3</sup>
| '''M'''⋅'''L'''<sup>−1</sup>⋅'''T'''<sup>−3</sup>
|-
| [[Physics:Irradiance|Irradiance]]<br/>[[Flux density]]
| ''E''<sub>e</sub>{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-alternative-symbol-radiometric}}<!-- E is typically used in radiometry and photometry. I is sometimes used as well, but conflicts with the radiometry usage of I for radiant intensity. -->
| watt per square metre
| W/m<sup>2</sup>
| '''M'''⋅'''T'''<sup>−3</sup>
| Radiant flux ''received'' by a ''surface'' per unit area. This is sometimes also confusingly called "intensity".
|-
| rowspan=2 style=white-space:nowrap | [[Physics:Irradiance|Spectral irradiance]]<br/>[[Physics:Spectral flux density|Spectral flux density]]
| ''E''<sub>e,ν</sub>{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-nu}}
| watt per square metre per hertz
| W⋅m<sup>−2</sup>⋅Hz<sup>−1</sup>
| '''M'''⋅'''T'''<sup>−2</sup>
| rowspan=2 | Irradiance of a ''surface'' per unit frequency or wavelength. This is sometimes also confusingly called "spectral intensity". Non-SI units of spectral flux density include [[Astronomy:Jansky|jansky]] (1&nbsp;Jy = 10<sup>−26</sup>&nbsp;W⋅m<sup>−2</sup>⋅Hz<sup>−1</sup>) and [[Astronomy:Solar flux unit|solar flux unit]] (1&nbsp;sfu = 10<sup>−22</sup>&nbsp;W⋅m<sup>−2</sup>⋅Hz<sup>−1</sup> = 10<sup>4</sup>&nbsp;Jy).
|-
| ''E''<sub>e,λ</sub>{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-lambda}}
| watt per square metre, per metre
| W/m<sup>3</sup>
| '''M'''⋅'''L'''<sup>−1</sup>⋅'''T'''<sup>−3</sup>
|-
| [[Physics:Radiosity (radiometry)|Radiosity]]
| ''J''<sub>e</sub>{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-alternative-symbol-radiometric}}<!-- W found to be used instead of M in older version of English WP, conflictive with W for radiant energy. -->
| watt per square metre
| W/m<sup>2</sup>
| '''M'''⋅'''T'''<sup>−3</sup>
| Radiant flux ''leaving'' (emitted, reflected and transmitted by) a ''surface'' per unit area. This is sometimes also confusingly called "intensity".
|-
| rowspan=2 | [[Physics:Radiosity (radiometry)|Spectral radiosity]]
| ''J''<sub>e,ν</sub>{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-nu}}
| watt per square metre per hertz
| W⋅m<sup>−2</sup>⋅Hz<sup>−1</sup>
| '''M'''⋅'''T'''<sup>−2</sup>
| rowspan=2 | Radiosity of a ''surface'' per unit frequency or wavelength. The latter is commonly measured in W⋅m<sup>−2</sup>⋅nm<sup>−1</sup>. This is sometimes also confusingly called "spectral intensity".
|-
| ''J''<sub>e,λ</sub>{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-lambda}}
| watt per square metre, per metre
| W/m<sup>3</sup>
| '''M'''⋅'''L'''<sup>−1</sup>⋅'''T'''<sup>−3</sup>
|-
| [[Physics:Radiant exitance|Radiant exitance]]
| ''M''<sub>e</sub>{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-alternative-symbol-radiometric}}<!-- W found to be used instead of M in older version of English WP, conflictive with W for radiant energy. -->
| watt per square metre
| W/m<sup>2</sup>
| '''M'''⋅'''T'''<sup>−3</sup>
| Radiant flux ''emitted'' by a ''surface'' per unit area. This is the emitted component of radiosity. "Radiant emittance" is an old term for this quantity. This is sometimes also confusingly called "intensity".
|-
| rowspan=2 | [[Physics:Radiant exitance|Spectral exitance]]
| ''M''<sub>e,ν</sub>{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-nu}}
| watt per square metre per hertz
| W⋅m<sup>−2</sup>⋅Hz<sup>−1</sup>
| '''M'''⋅'''T'''<sup>−2</sup>
| rowspan=2 | Radiant exitance of a ''surface'' per unit frequency or wavelength. The latter is commonly measured in W⋅m<sup>−2</sup>⋅nm<sup>−1</sup>. "Spectral emittance" is an old term for this quantity. This is sometimes also confusingly called "spectral intensity".
|-
| ''M''<sub>e,λ</sub>{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-lambda}}
| watt per square metre, per metre
| W/m<sup>3</sup>
| '''M'''⋅'''L'''<sup>−1</sup>⋅'''T'''<sup>−3</sup>
|-
| [[Physics:Radiant exposure|Radiant exposure]]
| ''H''<sub>e</sub>
| joule per square metre
| J/m<sup>2</sup>
| '''M'''⋅'''T'''<sup>−2</sup>
| Radiant energy received by a ''surface'' per unit area, or equivalently irradiance of a ''surface'' integrated over time of irradiation. This is sometimes also called "radiant fluence".
|-
| rowspan=2 | [[Physics:Radiant exposure|Spectral exposure]]
| ''H''<sub>e,ν</sub>{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-nu}}
| joule per square metre per hertz
| J⋅m<sup>−2</sup>⋅Hz<sup>−1</sup>
| '''M'''⋅'''T'''<sup>−1</sup>
| rowspan=2 | Radiant exposure of a ''surface'' per unit frequency or wavelength. The latter is commonly measured in J⋅m<sup>−2</sup>⋅nm<sup>−1</sup>. This is sometimes also called "spectral fluence".
|-
| ''H''<sub>e,λ</sub>{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-lambda}}
| joule per square metre, per metre
| J/m<sup>3</sup>
| '''M'''⋅'''L'''<sup>−1</sup>⋅'''T'''<sup>−2</sup>
|-
| [[Physics:Emissivity|Hemispherical emissivity]]
| ''ε''
| colspan=2 {{n/a}}
| '''1''' 
| Radiant exitance of a ''surface'', divided by that of a ''black body'' at the same temperature as that surface.
|-
| [[Physics:Emissivity|Spectral hemispherical emissivity]]
| ''ε''<sub>ν</sub><br>&nbsp;''or''<br>''ε''<sub>λ</sub>
| colspan=2 {{n/a}}
| '''1'''
| Spectral exitance of a ''surface'', divided by that of a ''black body'' at the same temperature as that surface.
|-
| [[Physics:Emissivity|Directional emissivity]]
| ''ε''<sub>Ω</sub>
| colspan=2 {{n/a}}
| '''1'''
| Radiance ''emitted'' by a ''surface'', divided by that emitted by a ''black body'' at the same temperature as that surface.
|-
| [[Physics:Emissivity|Spectral directional emissivity]]
| ''ε''<sub>Ω,ν</sub><br>&nbsp;''or''<br>''ε''<sub>Ω,λ</sub>
| colspan=2 {{n/a}}
| '''1'''
| Spectral radiance ''emitted'' by a ''surface'', divided by that of a ''black body'' at the same temperature as that surface.
|-
| [[Physics:Absorptance|Hemispherical absorptance]]
| ''A''
| colspan=2 {{n/a}}
| '''1'''
| Radiant flux ''absorbed'' by a ''surface'', divided by that received by that surface. This should not be confused with "[[Physics:Absorbance|absorbance]]".
|-
| [[Physics:Absorptance|Spectral hemispherical absorptance]]
| ''A''<sub>ν</sub><br>&nbsp;''or''<br>''A''<sub>λ</sub>
| colspan=2 {{n/a}}
| '''1'''
| Spectral flux ''absorbed'' by a ''surface'', divided by that received by that surface. This should not be confused with "[[Physics:Absorbance|spectral absorbance]]".
|-
| [[Physics:Absorptance|Directional absorptance]]
| ''A''<sub>Ω</sub>
| colspan=2 {{n/a}}
| '''1'''
| Radiance ''absorbed'' by a ''surface'', divided by the radiance incident onto that surface. This should not be confused with "[[Physics:Absorbance|absorbance]]".
|-
| [[Physics:Absorptance|Spectral directional absorptance]]
| ''A''<sub>Ω,ν</sub><br>&nbsp;''or''<br>''A''<sub>Ω,λ</sub>
| colspan=2 {{n/a}}
| '''1'''
| Spectral radiance ''absorbed'' by a ''surface'', divided by the spectral radiance incident onto that surface. This should not be confused with "[[Physics:Absorbance|spectral absorbance]]".
|-
| [[Physics:Reflectance|Hemispherical reflectance]]
| ''R''
| colspan=2 {{n/a}}
| '''1'''
| Radiant flux ''reflected'' by a ''surface'', divided by that received by that surface.
|-
| [[Physics:Reflectance|Spectral hemispherical reflectance]]
| ''R''<sub>ν</sub><br>&nbsp;''or''<br>''R''<sub>λ</sub>
| colspan=2 {{n/a}}
| '''1'''
| Spectral flux ''reflected'' by a ''surface'', divided by that received by that surface.
|-
| [[Physics:Reflectance|Directional reflectance]]
| ''R''<sub>Ω</sub>
| colspan=2 {{n/a}}
| '''1'''
| Radiance ''reflected'' by a ''surface'', divided by that received by that surface.
|-
| [[Physics:Reflectance|Spectral directional reflectance]]
| ''R''<sub>Ω,ν</sub><br>&nbsp;''or''<br>''R''<sub>Ω,λ</sub>
| colspan=2 {{n/a}}
| '''1'''
| Spectral radiance ''reflected'' by a ''surface'', divided by that received by that surface.
|-
| [[Physics:Transmittance|Hemispherical transmittance]]
| ''T''
| colspan=2 {{n/a}}
| '''1'''
| Radiant flux ''transmitted'' by a ''surface'', divided by that received by that surface.
|-
| [[Physics:Transmittance|Spectral hemispherical transmittance]]
| ''T''<sub>ν</sub><br>&nbsp;''or''<br>''T''<sub>λ</sub>
| colspan=2 {{n/a}}
| '''1'''
| Spectral flux ''transmitted'' by a ''surface'', divided by that received by that surface.
|-
| [[Physics:Transmittance|Directional transmittance]]
| ''T''<sub>Ω</sub>
| colspan=2 {{n/a}}
| '''1'''
| Radiance ''transmitted'' by a ''surface'', divided by that received by that surface.
|-
| [[Physics:Transmittance|Spectral directional transmittance]]
| ''T''<sub>Ω,ν</sub><br>&nbsp;''or''<br>''T''<sub>Ω,λ</sub>
| colspan=2 {{n/a}}
| '''1'''
| Spectral radiance ''transmitted'' by a ''surface'', divided by that received by that surface.
|-
| [[Physics:Attenuation coefficient|Hemispherical attenuation coefficient]]
| ''μ''
| reciprocal metre
| m<sup>−1</sup>
| '''L'''<sup>−1</sup>
| Radiant flux ''absorbed'' and ''scattered'' by a ''volume'' per unit length, divided by that received by that volume.
|-
| [[Physics:Attenuation coefficient|Spectral hemispherical attenuation coefficient]]
| ''μ''<sub>ν</sub><br>&nbsp;''or''<br>''μ''<sub>λ</sub>
| reciprocal metre
| m<sup>−1</sup>
| '''L'''<sup>−1</sup>
| Spectral radiant flux ''absorbed'' and ''scattered'' by a ''volume'' per unit length, divided by that received by that volume.
|-
| [[Physics:Attenuation coefficient|Directional attenuation coefficient]]
| ''μ''<sub>Ω</sub>
| reciprocal metre
| m<sup>−1</sup>
| '''L'''<sup>−1</sup>
| Radiance ''absorbed'' and ''scattered'' by a ''volume'' per unit length, divided by that received by that volume.
|-
| [[Physics:Attenuation coefficient|Spectral directional attenuation coefficient]]
| ''μ''<sub>Ω,ν</sub><br>&nbsp;''or''<br>''μ''<sub>Ω,λ</sub>
| reciprocal metre
| m<sup>−1</sup>
| '''L'''<sup>−1</sup>
| Spectral radiance ''absorbed'' and ''scattered'' by a ''volume'' per unit length, divided by that received by that volume.
|-
| style="text-align:center;" colspan=9 |See also: [[SI]]{{·}} [[Astronomy:Radiometry|Radiometry]]{{·}} [[Physics:Photometry (optics)|Photometry]]{{#if:{{{2|}}}|{{·}} ([[{{#ifeq:{{{2}}}|self||Photometry (optics)}}#table-si-photometry-units{{!}}Compare]])}}
|}
{{#if:{{{3|}}}||{{Reflist|group=nb}}}}<noinclude>
{{Documentation}}
<!--Please add this template's categories to the /doc subpage, not here - thanks!-->
</noinclude>