The Use of Terms and Units in Photometry – Implementation of the CIE System for Mesopic Photometry

CIE TN 004:2016
Division 2

This Technical Note gives guidance on the use of terms and units in photometry, particularly in relation to terms and units applicable for mesopic photometry. It can be used in conjunction with CIE 191:2010 Recommended System for Mesopic Photometry based on Visual Performance, which gives details of the method that should be used to calculate mesopic quantities and is fully compliant with the requirements of the SI system and the principles governing photometry, as published by the Bureau International des Poids et Mesures (BIPM).
The publication is written in English, consists of 11 pages and is freely downloadable from the CIE website.

The following members of TC 2-65 “Photometric measurements in the mesopic range“ took part in the preparation of this Technical Note. The committee comes under Division 2 “Physical measurement of light and radiation”.


  • Goodman, T.M. (Chair)    United Kingdom
  • Bergen, T.    Australia
  • Blattner, P.    Switzerland
  • Ohno, Y.    USA
  • Schanda, J. †    Hungary
  • Uchida, T.    Japan


  • Dam-Hansen, C.    Denmark
  • Schakel, M.    Netherlands
  • Shpak, M.    Finland