ਫਰਮਾ:SI light units ਲਈ ਸਰੋਤ ਵੇਖੋ

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|- 
! colspan="2"| Quantity
! colspan="2"| Unit<!-- &nbsp;(SI) -->
! Dimension<!-- &nbsp;(SI) -->
! rowspan="2"| Notes
|- 
! <small>Name</small>
! <small>Symbol</small>{{#tag:ref|[[Standards organization]]s recommend that photometric quantities be denoted with a suffix "v" (for "visual") to avoid confusion with radiometric or [[photon]] quantities. For example: ''USA Standard Letter Symbols for Illuminating Engineering'' USAS Z7.1-1967, Y10.18-1967|group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-suffix-v}}
! <small>Name</small>
! <small>Symbol</small>
! <small>Symbol</small>
|- 
| [[Luminous energy]]
| ''Q''<sub>v</sub>&nbsp;{{#tag:ref|Alternative symbols sometimes seen: ''W'' for luminous energy, ''P'' or ''F'' for luminous flux, and ''&rho;'' or ''K'' for luminous efficacy.|group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-alternative-symbol-photometric}}<!-- Luminous energy alternatives: Q is used throughout literature. Palmer recommends W (typo for E?) as acceptable alternative. -->
| [[lumen second]]
| [[lumen (unit)|lm]]⋅s
| '''T'''⋅'''J'''&nbsp;{{#tag:ref|"'''J'''" here is the symbol for the [[Dimension of a physical quantity|dimension]] of luminous intensity, not the symbol for the [[Units of measurement|unit]] joules.|group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-dimension-J}}<!-- [[http://www.bipm.org/utils/common/pdf/si_brochure_8.pdf]] [[http://www.ptb.de/cms/fileadmin/internet/publikationen/DasInternationaleEinheitensystem.pdf]] -->
| Units are sometimes called ''talbots''.
|- 
| [[Luminous flux]] / luminous power
| ''Φ''<sub>[[Luminosity function|v]]</sub>&nbsp;{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-alternative-symbol-photometric}}<!-- Luminous flux alternatives: Phi_v is used throughout the literature, Palmer uses Phi_p as well, but recommends P as acceptable alternative and uses F in HTML docs. P is used in Slovakian WP, F is still partially used in English WP. -->
| [[lumen (unit)|lumen]] (=&nbsp;cd⋅[[steradian|sr]])
| lm
| '''J'''&nbsp;{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-dimension-J}}
| Luminous energy per unit time.
|- 
| [[Luminous intensity]]
| ''I''<sub>v</sub>
| [[candela]] (=&nbsp;lm/sr)
| [[candela|cd]]
| '''J'''&nbsp;{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-dimension-J}}
| Luminous power per unit [[solid angle]].
|- 
| [[Luminance]]
| ''L''<sub>v</sub>
| [[candela per square metre]]
| cd/m<sup>2</sup>
| '''L'''<sup>−2</sup>⋅'''J'''
| Luminous power per unit solid angle per unit ''projected'' source area. Units are sometimes called ''[[nit_(unit)|nit]]s''.
|- 
| [[Illuminance]]
| ''E''<sub>v</sub>
| [[lux]] (=&nbsp;lm/m<sup>2</sup>)
| [[lux|lx]]
| '''L'''<sup>−2</sup>⋅'''J'''
| Luminous power ''incident'' on a surface.
|-
| [[Luminous exitance]] / luminous emittance
| ''M''<sub>v</sub>
| lux
| lx
| '''L'''<sup>−2</sup>⋅'''J'''
| Luminous power ''emitted'' from a surface.
|- 
| [[Luminous exposure]]
| ''H''<sub>v</sub>
| [[lux second]]
| lx⋅s
| '''L'''<sup>−2</sup>⋅'''T'''⋅'''J'''
| 
|- 
| [[Luminous energy density]]
| ''ω''<sub>v</sub>
| lumen second per cubic metre
| lm⋅s⋅m<sup>−3</sup>
| '''L'''<sup>−3</sup>⋅'''T'''⋅'''J'''
| 
|- 
| [[Luminous efficacy]]
| ''η''&nbsp;{{#tag:ref||group={{#if:{{{3|}}}|{{{3}}}|nb}}|name=note-alternative-symbol-photometric}}<!-- Examples of usage: eta seems to be in general use, rho has been seen in Slovakian WP, K in English literature. -->
| lumen per [[watt]]
| lm/[[watt|W]]
| '''M'''<sup>−1</sup>⋅'''L'''<sup>−2</sup>⋅'''T'''<sup>3</sup>⋅'''J'''
| Ratio of luminous flux to [[radiant flux]] or power consumption, depending on context.
|- 
| [[Luminous efficiency]] / luminous coefficient
| ''V''
| 
| 
| 1
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|- 
| style="text-align:center;" colspan=9 |See also: [[SI]]{{&middot;}} [[Photometry (optics)|Photometry]]{{&middot;}} [[Radiometry]]{{#if:{{{2|}}}|{{&middot;}} ([[{{#ifeq:{{{2}}}|self||Radiometry}}#table-si-radiometry-units{{!}}Compare]])}}
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