People suffer from four types of refractive eye problems:
A refractive error occurs when light entering the eye is not precisely focused on the retina at the back of the eye, causing blurred vision. Normally, light rays passing through the cornea, pupil, and lens are focused directly on the retina, allowing you to perceive objects clearly.
Hypermetropia eye problems
Astigmatism eye problems
Astigmatism causes blurred vision at all distances. This is caused by an “egg” shaped cornea, where light rays are focused both behind and in front of the retina.