This page documents an OPTIMADE Unit Definition. See https://schemas.optimade.org/ for more information.
ID: https://schemas.optimade.org/defs/v1.2/units/si/1983/base/candela
Definition name: candela
Unit name: candela
Latin symbol: cd
Display symbol: cd
Description: The candela is the SI base unit of luminous intensity in a given direction defined from the luminous intensity of monochromatic radiation at a specific frequency and radiant intensity at the 16th CGPM Meeting in 1979; implicitly redefined via the redefinition of the metre at the 17th CGPM Meeting in 1983.
"The candela is the luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency 540×10¹² hertz and that has a radiant intensity in that direction of 1/683 watt per steradian." [16th CGPM Meeting (1979), resolution 3].
Following the redefinition of the metre at the 17th CGPM Meeting in 1983, resolution 1, the implicitly redefined candela references:
Resources:
JSON definition:
{
"$id": "https://schemas.optimade.org/defs/v1.2/units/si/1983/base/candela",
"$schema": "https://schemas.optimade.org/meta/v1.2/optimade/physical_unit_definition.json",
"title": "candela",
"symbol": "cd",
"display-symbol": "cd",
"description": "The candela is the SI base unit of luminous intensity in a given direction defined from the luminous intensity of monochromatic radiation at a specific frequency and radiant intensity at the 16th CGPM Meeting in 1979; implicitly redefined via the redefinition of the metre at the 17th CGPM Meeting in 1983.\n\n\"The candela is the luminous intensity, in a given direction, of a source that emits monochromatic radiation of frequency 540\u00d710\u00b9\u00b2 hertz and that has a radiant intensity in that direction of 1/683 watt per steradian.\" [16th CGPM Meeting (1979), resolution 3].\n\nFollowing the redefinition of the metre at the 17th CGPM Meeting in 1983, resolution 1, the implicitly redefined candela references:\n\n- the SI 1967 derived hertz unit (https://schemas.optimade.org/defs/v1.2/units/si/1967/named/hertz).\n- the SI 1983 derived watt unit (https://schemas.optimade.org/defs/v1.2/units/si/1983/named/watt).\n- the SI 1960 supplementary unit steradian (https://schemas.optimade.org/defs/v1.2/units/si/1960/supplementary/steradian).",
"resources": [
{
"relation": "Definition at the 41st CIPM meeting (1946), resolution 2",
"resource-id": "https://www.bipm.org/en/committees/ci/cipm/41-1946/resolution-2"
},
{
"relation": "Inclusion in SI at the establishment of the SI unit system at the 11th CGPM meeting (1960), resolution 12.",
"resource-id": "https://www.bipm.org/en/committees/cg/cgpm/11-1960/resolution-12"
},
{
"relation": "Redefinition of the metre at the 17th CGPM meeting (1983), resolution 1",
"resource-id": "https://www.bipm.org/en/committees/cg/cgpm/17-1983/resolution-1"
},
{
"relation": "Redefinition of the second at the 13th CGPM meeting (1967), resolution 1",
"resource-id": "https://www.bipm.org/en/committees/cg/cgpm/13-1967/resolution-1"
},
{
"relation": "Wikipedia article describing the unit",
"resource-id": "https://en.wikipedia.org/wiki/Candela"
}
],
"standard": {
"name": "si",
"year": 1983,
"category": "base",
"symbol": "cd"
},
"x-optimade-definition": {
"label": "candela_si_1983_base",
"kind": "unit",
"format": "1.2",
"version": "1.2.0",
"name": "candela"
}
}