The diopter is a unit of measurement used to describe how well a person sees.
With diopters, the farther a measurement is from 0, the more severe the refractive error. For example, if a person has -4 diopters of nearsightedness, it means that the farthest point you can see clearly is one-fourth of a meter (about 10 inches) from your eye.
|Primary Medical Reviewer||Kathleen Romito, MD - Family Medicine|
|Specialist Medical Reviewer||Christopher J. Rudnisky, MD, MPH, FRCSC - Ophthalmology|
|Last Revised||June 24, 2011|
WebMD Medical Reference from Healthwise