Age effects on mesopic and scotopic anisocoria determined in vehicle drivers.

Abstract

The diameter of the pupil affects a person´s vision in a complex manner. As the pupil dilates, it allows more light to enter the eye and stimulate the retina, reducing blur caused by diffraction to a minimum. A narrow pupil, on the other hand, reduces the negative effects of these aberrations on the crystaline lens. In general, a pupil diameter of 3 to 6 mm increases clarity of vision. Owing to the adaptation process, humans can tolerate a difference in luminance conditions from 1 to 10000000 cd/m2. The spectrum of visual sensitivity is so broad that in a graph, the intensity of light has to be plotted on a logarithmic scale.