ISO 31-6
ISO 31-6 is the part of international standard ISO 31 that defines names and symbols for quantities and units related to light and related electromagnetic radiations. It is superseded by ISO 80000-7.
Its definitions include:
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Wikipedia
ISO 31-6 is the part of international standard ISO 31 that defines names and symbols for quantities and units related to light and related electromagnetic radiations. It is superseded by ISO 80000-7.
Its definitions include: