Legibility of Pictograms on Coloured Surfaces Under Different Illuminants

Abstract

Ambient lighting conditions, under which the packaging is viewed, determine to a large extent the visual perception of the information which it carries. This paper investigated how different illuminants affect the legibility of pictograms intended for the application on different coloured packaging. 87 participants observed the pictograms on blue, red and yellow coloured backgrounds in a viewing booth which assured controlled lightning conditions. The results indicated that the legibility of pictograms varied in dependence of the background colour used. The best performance was obtained by pictograms designed on a yellow background. Furthermore, it was found that the pictograms were significantly more legible under illuminant ‘A’ compared to the other tested illuminants.