Understanding how vision works requires a basic knowledge of how the eye focuses light. Ideally, the eye is able to perfectly focus light rays coming through the cornea onto the retina. When the curve of the cornea is too steep, too flat or irregular, light rays do not focus directly on the retina, which results in impaired vision.
These types of imperfections are called “refractive errors.” Some of the most common types of refractive errors are nearsightedness, farsightedness and astigmatism.
To understand the terms that your providers may use, it can be helpful to have a general understanding of the anatomy of the eye. This short video will give you an overview of how the eye works.