Abstract

The pupil is an important componant of the optics of the human eye. Pupil centration and diameter contribute to retinal image quality¹,². It has been previously shown that the geometric center of the entrance pupil of the eye may shift during mydriasis, either pharmacologically induced or naturally induced by darkness³-⁶. However, the repeatability of the pupil displacement has not been studied and it does not seem to be known whether this shift occurs at random or not for a given subject. This information is important for photorefractive surgery⁷ because the relative centration of the ablated corneal zone with respect to the pupil is a critical issue for retinal image quality. Pupil displacement with respect to this corneal zone occurring during pupil dilation may introduce a comatic aberration and this could explain some complaints reported by patients at night.

© 1997 Optical Society of America