Sukanthi: "{{anchor|table-si-radiometry-units}} {|class="wikitable plainrowheaders" |+ {{navbar-header |1={{resize|130%|{{#if:{{{1|}}}|Table {{{1}}}. }}SI radiometry units}}|2=SI radiometry units}} |- ! scope="col" colspan="2" | Quantity ! scope="col" colspan="2" | Unit ! scope="col" rowspan="2" | Dimension ! scope="col" rowspan="2" | Notes |- ! scope="col" | Name..."-இப்பெயரில் புதிய பக்கம் உருவாக்கப்பட்டுள்ளது

2025-09-22T06:39:37Z

"{{anchor|table-si-radiometry-units}} {|class="wikitable plainrowheaders" |+ {{navbar-header |1={{resize|130%|{{#if:{{{1|}}}|Table {{{1}}}. }}SI radiometry units}}|2=SI radiometry units}} |- ! scope="col" colspan="2" | Quantity ! scope="col" colspan="2" | Unit ! scope="col" rowspan="2" | Dimension ! scope="col" rowspan="2" | Notes |- ! scope="col" | Name..."-இப்பெயரில் புதிய பக்கம் உருவாக்கப்பட்டுள்ளது

புதிய பக்கம்

{{anchor|table-si-radiometry-units}}
{|class="wikitable plainrowheaders"
|+ {{navbar-header |1={{resize|130%|{{#if:{{{1|}}}|Table {{{1}}}. }}SI radiometry units}}|2=SI radiometry units}}
|-
! scope="col" colspan="2" | Quantity
! scope="col" colspan="2" | Unit
! scope="col" rowspan="2" | Dimension
! scope="col" rowspan="2" | Notes
|-
! scope="col" | Name
! scope="col" | Symbol{{#tag:ref|[[Standards organization]]s recommend that radiometric [[Physical quantity|quantities]] should be denoted with suffix "e" (for "energetic") to avoid confusion with photometric or [[photon]] quantities.|group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-e}}
! scope="col" | Name
! scope="col" | Symbol
|-
! scope="row" | [[Radiant energy]]
| {{math|''Q''{{sub|e}}}}{{#tag:ref|Alternative symbols sometimes seen: {{mvar|W}} or {{mvar|E}} for radiant energy, {{mvar|P}} or {{mvar|F}} for radiant flux, {{mvar|I}} for irradiance, {{mvar|W}} for radiant exitance.|group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-alternative-symbol-radiometric}}
| [[joule]]
| [[Joule|J]]
| '''M'''⋅'''L'''{{sup|2}}⋅'''T'''{{sup|−2}}
| Energy of electromagnetic radiation.
|-
! scope="row" style=white-space:nowrap | [[Radiant energy density]]
| {{math|''w''{{sub|e}}}}
| joule per cubic metre
| J/m{{sup|3}}
| '''M'''⋅'''L'''{{sup|−1}}⋅'''T'''{{sup|−2}}
| Radiant energy per unit volume.
|-
! scope="row" | [[Radiant flux]]
| {{math|Φ{{sub|e}}}}{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-alternative-symbol-radiometric}}
| [[watt]]
| [[Watt|W]] = J/s
| '''M'''⋅'''L'''{{sup|2}}⋅'''T'''{{sup|−3}}
| Radiant energy emitted, reflected, transmitted or received, per unit time. This is sometimes also called "radiant power", and called [[luminosity]] in astronomy.
|-
! scope="row" rowspan=2 | [[Radiant flux|Spectral flux]]
| {{math|Φ{{sub|e,''ν''}}}}{{#tag:ref|Spectral quantities given per unit [[frequency]] are denoted with suffix "''[[ν]]''" (Greek letter [[Nu (letter)|nu]], not to be confused with a letter "v", indicating a photometric quantity.)|group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-nu}}
| watt per [[hertz]]
| W/[[Hertz|Hz]]
| '''M'''⋅'''L'''{{sup|2}}⋅'''T'''{{sup| −2}}
| rowspan=2 | Radiant flux per unit frequency or wavelength. The latter is commonly measured in W⋅nm{{sup|−1}}.
|-
| {{math|Φ{{sub|e,''λ''}}}}{{#tag:ref|Spectral quantities given per unit [[wavelength]] are denoted with suffix "''[[λ]]''".|group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-lambda}}
| watt per metre
| W/m
| '''M'''⋅'''L'''⋅'''T'''{{sup|−3}}
|-
! scope="row" | [[Radiant intensity]]
| {{math|''I''{{sub|e,Ω}}}}{{#tag:ref|Directional quantities are denoted with suffix "[[Ω]]".|group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-omega}}
| watt per [[steradian]]
| W/[[steradian|sr]]
| '''M'''⋅'''L'''{{sup|2}}⋅'''T'''{{sup|−3}}
| Radiant flux emitted, reflected, transmitted or received, per unit solid angle. This is a ''directional'' quantity.
|-
! scope="row" rowspan=2 | [[Radiant intensity|Spectral intensity]]
| {{math|''I''{{sub|e,Ω,''ν''}}}}{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-nu}}
| watt per steradian per hertz
| W⋅sr{{sup|−1}}⋅Hz{{sup|−1}}
| '''M'''⋅'''L'''{{sup|2}}⋅'''T'''{{sup|−2}}
| rowspan=2 | Radiant intensity per unit frequency or wavelength. The latter is commonly measured in W⋅sr{{sup|−1}}⋅nm{{sup|−1}}. This is a ''directional'' quantity.
|-
| {{math|''I''{{sub|e,Ω,''λ''}}}}{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-lambda}}
| watt per steradian per metre
| W⋅sr{{sup|−1}}⋅m{{sup|−1}}
| '''M'''⋅'''L'''⋅'''T'''{{sup|−3}}
|-
! scope="row" | [[Radiance]]
| {{math|''L''{{sub|e,Ω}}}}{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-omega}}
| watt per steradian per square metre
| W⋅sr{{sup|−1}}⋅m{{sup|−2}}
| '''M'''⋅'''T'''{{sup|−3}}
| 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".
|-
! scope="row" rowspan=2 style=white-space:nowrap | [[Spectral radiance]]</br>Specific intensity
| {{math|''L''{{sub|e,Ω,''ν''}}}}{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-nu}}
| watt per steradian per square metre per hertz
| W⋅sr{{sup|−1}}⋅m{{sup|−2}}⋅Hz{{sup|−1}}
| '''M'''⋅'''T'''{{sup|−2}}
| rowspan=2 | Radiance of a ''surface'' per unit frequency or wavelength. The latter is commonly measured in W⋅sr{{sup|−1}}⋅m{{sup|−2}}⋅nm{{sup|−1}}. This is a ''directional'' quantity. This is sometimes also confusingly called "spectral intensity".
|-
| {{math|''L''{{sub|e,Ω,''λ''}}}}{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-lambda}}
| watt per steradian per square metre, per metre
| W⋅sr{{sup|−1}}⋅m{{sup|−3}}
| '''M'''⋅'''L'''{{sup|−1}}⋅'''T'''{{sup|−3}}
|-
! scope="row" | [[Irradiance]]<br/>[[Flux density]]
| {{math|''E''{{sub|e}}}}{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-alternative-symbol-radiometric}}
| watt per square metre
| W/m{{sup|2}}
| '''M'''⋅'''T'''{{sup|−3}}
| Radiant flux ''received'' by a ''surface'' per unit area. This is sometimes also confusingly called "intensity".
|-
! scope="row" rowspan=2 style=white-space:nowrap | [[Irradiance|Spectral irradiance]]<br/>[[Spectral flux density]]
| {{math|''E''{{sub|e,''ν''}}}}{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-nu}}
| watt per square metre per hertz
| W⋅m{{sup|−2}}⋅Hz{{sup|−1}}
| '''M'''⋅'''T'''{{sup|−2}}
| 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 [[jansky]] ({{val|1|u=Jy}} = {{val||e=−26|u=W⋅m{{sup|−2}}⋅Hz{{sup|−1}}}}) and [[solar flux unit]] ({{val|1|u=sfu}} = {{val||e=−22|u=W⋅m{{sup|−2}}⋅Hz{{sup|−1}}}} = {{val||e=4|u=Jy}}).
|-
| {{math|''E''{{sub|e,''λ''}}}}{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-lambda}}
| watt per square metre, per metre
| W/m{{sup|3}}
| '''M'''⋅'''L'''{{sup|−1}}⋅'''T'''{{sup|−3}}
|-
! scope="row" | [[Radiosity (radiometry)|Radiosity]]
| {{math|''J''{{sub|e}}}}{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-alternative-symbol-radiometric}}
| watt per square metre
| W/m{{sup|2}}
| '''M'''⋅'''T'''{{sup|−3}}
| Radiant flux ''leaving'' (emitted, reflected and transmitted by) a ''surface'' per unit area. This is sometimes also confusingly called "intensity".
|-
! scope="row" rowspan=2 | [[Radiosity (radiometry)|Spectral radiosity]]
| {{math|''J''{{sub|e,''ν''}}}}{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-nu}}
| watt per square metre per hertz
| W⋅m{{sup|−2}}⋅Hz{{sup|−1}}
| '''M'''⋅'''T'''{{sup|−2}}
| rowspan=2 | Radiosity of a ''surface'' per unit frequency or wavelength. The latter is commonly measured in W⋅m{{sup|−2}}⋅nm{{sup|−1}}. This is sometimes also confusingly called "spectral intensity".
|-
| {{math|''J''{{sub|e,''λ''}}}}{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-lambda}}
| watt per square metre, per metre
| W/m{{sup|3}}
| '''M'''⋅'''L'''{{sup|−1}}⋅'''T'''{{sup|−3}}
|-
! scope="row" | [[Radiant exitance]]
| {{math|''M''{{sub|e}}}}{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-alternative-symbol-radiometric}}
| watt per square metre
| W/m{{sup|2}}
| '''M'''⋅'''T'''{{sup|−3}}
| 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".
|-
! scope="row" rowspan=2 | [[Radiant exitance|Spectral exitance]]
| {{math|''M''{{sub|e,''ν''}}}}{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-nu}}
| watt per square metre per hertz
| W⋅m{{sup|−2}}⋅Hz{{sup|−1}}
| '''M'''⋅'''T'''{{sup|−2}}
| rowspan=2 | Radiant exitance of a ''surface'' per unit frequency or wavelength. The latter is commonly measured in W⋅m{{sup|−2}}⋅nm{{sup|−1}}. "Spectral emittance" is an old term for this quantity. This is sometimes also confusingly called "spectral intensity".
|-
| {{math|''M''{{sub|e,''λ''}}}}{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-lambda}}
| watt per square metre, per metre
| W/m{{sup|3}}
| '''M'''⋅'''L'''{{sup|−1}}⋅'''T'''{{sup|−3}}
|-
! scope="row" | [[Radiant exposure]]
| {{math|''H''{{sub|e}}}}
| joule per square metre
| J/m{{sup|2}}
| '''M'''⋅'''T'''{{sup|−2}}
| 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".
|-
! scope="row" rowspan=2 | [[Radiant exposure|Spectral exposure]]
| {{math|''H''{{sub|e,''ν''}}}}{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-nu}}
| joule per square metre per hertz
| J⋅m{{sup|−2}}⋅Hz{{sup|−1}}
| '''M'''⋅'''T'''{{sup|−1}}
| rowspan=2 | Radiant exposure of a ''surface'' per unit frequency or wavelength. The latter is commonly measured in J⋅m{{sup|−2}}⋅nm{{sup|−1}}. This is sometimes also called "spectral fluence".
|-
| {{math|''H''{{sub|e,''λ''}}}}{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-lambda}}
| joule per square metre, per metre
| J/m{{sup|3}}
| '''M'''⋅'''L'''{{sup|−1}}⋅'''T'''{{sup|−2}}
|-
| style="text-align:center;" colspan=6 | See also: {{hlist|class=inline|[[SI]]|[[Radiometry]]|[[Photometry (optics)|Photometry]]{{#if:{{{2|}}}|{{!}}([[{{#ifeq:{{{2}}}|self||Photometry (optics)}}#table-si-photometry-units{{!}}Compare]])}}}}
|}
{{#if:{{{3|}}}||{{Reflist|group=nb}}}}<noinclude>
{{Documentation}}

</noinclude>

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