Refractive error in your eye happen when the shape of your eyeball prevents light from correctly focusing on your retina. If your eyeball is longer than normal (oblong) or shorter than normal, it changes the shape of your cornea and lens, causing an abnormal image to be projected on your retina in the back of your eye. This distorts the visual messages to your brain. The lens in your eye can also change shape with age — another cause of refractive error issues.
Refraction is normally defined as the bending of light rays passing through an object. Eye refraction is the same: the bending of light as it passes through your cornea and lens. Your vision works by bending light that passes through your cornea and lens, where it’s then focused on your retina. Your retina translates these light rays into electrochemical messages and sends them to your brain through the optic nerve. Your brain interprets this information into the imagery you see.
If you are having any abnormal visual symptoms, you should always be evaluated with a thorough consultation and examination by a physician for an accurate diagnosis and treatment plan as it may be a symptom or sign of a serious illness or condition.