The e-ILV provides free access to all the terms and definitions contained in the international standard CIE S 017:2020 ILV: International Lighting Vocabulary, 2nd edition.

To search for another term please use  "Back to the list" to return to the main page or the e-ILV.

For the complete set of terms and definitions CIE S 017:2020 can be purchased from the CIE Webshop. Members of a CIE National Committee or Associate National Committee have access to a 66,7 % discount on the purchase price of the standard.


mesopic vision

vision by the normal eye intermediate between photopic vision and scotopic vision

Note 1 to entry: In mesopic vision, both the cones and the rods are active.

Note 2 to entry: See also CIE 191:2010 Recommended System for Mesopic Photometry based on Visual Performance.

Note 3 to entry: This entry was numbered 845-02-11 in IEC 60050-845:1987.

Note 4 to entry: This entry was numbered 17-763 in CIE S 017:2011.

Publication date: 2020-12
Copyright © CIE 2020. All Rights Reserverd.