Category:Photometry
Photometry is the science of measurement of light, in terms of its apparent brightness to the human eye. It is distinct from radiometry, which is the science of measurement of light in terms of absolute power. Note that this term is used differently in astronomy. For information on the astronomical method, see Photometry (astronomy). Lua error in package.lua at line 80: module 'Module:Category main article' not found.
Quantity | Unit | Dimension | Notes | |||||
---|---|---|---|---|---|---|---|---|
Name | Symbol[nb 1]r | Name | Symbol | Symbol | ||||
Luminous energy | Qv [nb 2] | lumen second | lm⋅s | T⋅J [nb 3] | Units are sometimes called talbots. | |||
Luminous flux / luminous power | Φv [nb 2] | lumen (= cd⋅sr) | lm | J [nb 3] | Luminous energy per unit time. | |||
Luminous intensity | Iv | candela (= lm/sr) | cd | J [nb 3] | Luminous power per unit solid angle. | |||
Luminance | Lv | candela per square metre | cd/m2 | L−2⋅J | Luminous power per unit solid angle per unit projected source area. Units are sometimes called nits. | |||
Illuminance | Ev | lux (= lm/m2) | lx | L−2⋅J | Luminous power incident on a surface. | |||
Luminous exitance / luminous emittance | Mv | lux | lx | L−2⋅J | Luminous power emitted from a surface. | |||
Luminous exposure | Hv | lux second | lx⋅s | L−2⋅T⋅J | ||||
Luminous energy density | ωv | lumen second per cubic metre | lm⋅s⋅m−3 | L−3⋅T⋅J | ||||
Luminous efficacy | η [nb 2] | lumen per watt | lm/W | M−1⋅L−2⋅T3⋅J | Ratio of luminous flux to radiant flux or power consumption, depending on context. | |||
Luminous efficiency / luminous coefficient | V | 1 | ||||||
See also: SI · Photometry · Radiometry |
<templatestyles src="Reflist/styles.css" />
Cite error: Invalid <references>
tag; parameter "group" is allowed only.
<references />
, or <references group="..." />
![]() |
Wikimedia Commons has media related to Photometry. |
Cite error: <ref>
tags exist for a group named "nb", but no corresponding <references group="nb"/>
tag was found, or a closing </ref>
is missing
Subcategories
This category has the following 6 subcategories, out of 6 total.
C
U
Pages in category "Photometry"
The following 40 pages are in this category, out of 40 total.