A unified formula for light-adapted pupil size

J Vis. 2012 Sep 25;12(10):12. doi: 10.1167/12.10.12.

Abstract

The size of the pupil has a large effect on visual function, and pupil size depends mainly on the adapting luminance, modulated by other factors. Over the last century, a number of formulas have been proposed to describe this dependence. Here we review seven published formulas and develop a new unified formula that incorporates the effects of luminance, size of the adapting field, age of the observer, and whether one or both eyes are adapted. We provide interactive demonstrations and software implementations of the unified formula.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Review

MeSH terms

  • Adaptation, Ocular / physiology*
  • Humans
  • Models, Theoretical*
  • Photoperiod*
  • Pupil / physiology*