Relation between spherical refractive error and visual acuity.

The relation between a spherical refractive error and visual acuity is investigated and the results compared with previous studies. This study, unlike most of the previous studies, presents a mathematical model that includes a pupil size factor. It also examines a theoretical relation between refractive error and visual acuity which predicts that there should be a linear relation among refractive error (E), the pupil diameter (D), and minimum angle of resolution (A), over a wide range of refractive errors.