Structure, how it works,correcting eye problems
Parts of the eye
The iris is a thin, circular structure in the eye, responsible for controlling the diameter and size of the pupil and thus the amount of light reaching the retina.
The (crystalline) lens is a transparent structure that, along with the cornea, helps to refract to the retina.
Light coming by the cornea and crystalline lens then reaches the retina, the light-sensitive inner lining of the back of the eye. The retina acts like an image sensor of a digital camera, converting optical images into signals. The optic nerve then transmits these signals to the visual cortex, the part of the brain that controls the sense of sight.
Correcting eye problems
Now, several modern approaches to corrective eye surgery are from laser reshaping of the eye's surface in operations like LASIK and PRK to surgical insertion of artificial lenses to correct eyesight.