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Section 7-62 entries

7-6.1

radiance

URNurn:iso:std:iso:80000:-7:ed-2:en:item:7-6.1

https://metanorma.github.io/isq-smart/quantities/part-7/t7-6.1
urn:iso:std:iso:80000:-7:ed-2:en:item:7-6.1

ISQ Identifiers

ISO

urn:iso:std:iso:80000:-7:ed-2:en:item:7-6.1

IEC

urn:iec:std:iec:80000-7:2019:::item:7-6.1

Designations

ENradiance

FRluminance énergétique

FRradiance

Symbol

L_{e}

(L)

Notation systems

Rendered

L_{e}

Rendered

(L)

AsciiMath

L_"e"

AsciiMath

(L)

LaTeX

L_{\text{e}}

LaTeX

( L )

Definition

density of radiant intensity with respect to projected area in a specified direction at a specified point on a real or imaginary surface, expressed by

L_{e} = \frac{d l_{e}}{d A} \frac{1}{cos α}

where $I_{e}$ is radiant intensity (radiant intensity), A is area (ISO 80000-3: Space and time), and $α$ is the angle between the normal to the surface at the specified point and the specified direction

quotient de l'intensité énergétique reçue par un élément d'une surface réelle ou fictive contenant un point spécifié par l'aire de la projection de cet élément dans une direction spécifiée, exprimée par

L_{e} = \frac{d l_{e}}{d A} \frac{1}{cos α}

où $I_{e}$ est l'intensité énergétique (radiant intensity), A est l'aire (ISO 80000-3: Space and time) et $α$ est l'angle entre la normale à la surface au point spécifié et la direction spécifiée

Units

\frac{W}{s r \cdot m^{2}}

watt per steradian square metre

View related quantities →

k g \cdot s^{- 3} \cdot s r^{- 1}

kilogram per second cubed steradian

View related quantities →

Notes

Referenced by

spectral radiance irradiance luminance photon radiance radiance factor

Concept HierarchyPendrill (2024)

L²L² quantitiesLevel 0 · Kind

Broader concepts

◇ L² quantities

Characterizes

● photon

Ontology
isq:Quantity smart:TermEntry

Class Hierarchy

smart:Entity smart:TermEntryisq:Quantity

A physical quantity as defined in ISO/IEC 80000, with associated symbols, definitions, and units of measurement.

Instance IRI

isq:t7-6.1

Properties

isq:QuantityShape

Property	Value
rdf:type	isq:Quantity smart:TermEntry
dcterms:identifier	7-6.1
skosxl:prefLabel	"radiance"@en
skosxl:altLabel	"L_"e""@en"(L)"@en
skos:definition	density of radiant intensity with respect to projected area in a specified direction at a specified point on a real or i…
skos:note	See also <<cls-0.1>>. For Planckian radiation, [stem%unnumbered] ++++ L_"e" = sigma/pi T^4 ++++ where stem:[T] is the…
isq:hasUnit	W/(srm^2) (watt per steradian square metre)kgs^(-3)*sr^(-1) (kilogram per second cubed steradian)
isq:hasDimension	isq:Dimension
smart:hasBindingnessType	bindingness-type:normative
dcterms:isPartOf	isq:part-7

Related Entities

isq:QuantityShape isq:part-7 isq:Unit isq:Dimension isq:hasDimension smart:TermEntry