General V(λ) mismatch index: History, current state and new ideas

U. Krüger, A. Ferrero, A. Thorseth, V. Mantela*, A. Sperling

*Corresponding author for this work

Research output: Contribution to journalArticleScientificpeer-review

1 Citation (Scopus)
62 Downloads (Pure)


The general V(λ) mismatch index f1′ specifies the mismatch between the relative spectral responsivity of a photometer, and the spectral luminous efficiency function for photopic vision, V(λ). A short review of its historical development explains the reasons for the current definition and which adjustments may be helpful in the future. The properties of the current definition are described in detail. It is very likely that photometers will be calibrated with a white light-emitting diode (LED) light source as the reference in the future. This might involve the need for a more appropriate definition of the general V(λ) mismatch index, either by using a different normalisation in f1′ for the relative spectral responsivity of the photometer or by introducing a different type of function for assessing the mismatch. On the other hand, the measurement of coloured LEDs is also becoming increasingly important. So, is a single general mismatch index for white and coloured light sources sufficient?
Original languageEnglish
Pages (from-to)420-432
Number of pages13
JournalLighting Research and Technology
Issue number4-5
Early online date15 Apr 2023
Publication statusPublished - 1 Jun 2023
MoE publication typeA1 Journal article-refereed


Dive into the research topics of 'General V(λ) mismatch index: History, current state and new ideas'. Together they form a unique fingerprint.

Cite this