Learn how the eye works

How the eye works

Light enters the eye through the cornea (the clear front window of the eye). The amount of light that enters is controlled by the pupil. In people with perfect vision, the light focuses directly on the retina and the image is sent to the brain. In many people with vision problems, light does not focus directly on the retina. This produces visual distortions.

Common Vision Problems

Nearsightedness (Myopia)

Nearsightedness is a visual problem that affects about one-third of the population. People who are nearsighted are able to clearly see items close up, but have trouble with their distance vision. Nearsightedness occurs when the eyeball is slightly longer than usual, causing light to focus on a point in front of the retina rather than on its surface. Nearsightedness can be corrected with glasses, contacts, or refractive surgery.

Farsightedness (Hyperopia)

Farsightedness affects about one-forth of the population. Farsighted people have no problem seeing distant objects, but struggle with seeing nearby items. Hyperopia occurs when the eyeball is shorter than usual, causing light rays to focus behind the retina instead of directly on it. Refractive surgery, glasses, and contact lenses can all be used to correct this visual problem.


Astigmatism usually occurs due to an irregularly shaped cornea, but can sometimes be the result of an irregularly shaped lens. In most cases, people with astigmatism experience distorted vision because their cornea has an oblong shape rather than a spherical shape. This causes light rays to focus on two points at the back of the eye, instead of just one. Astigmatism can occur alone or in conjunction with myopia or hyperopia. It can be corrected with rigid contact lenses (RCLs), toric contact lenses, or refractive surgery. For more information about vision correction options for astigmatism, contact our practice.


Presbyopia is different from other common visual problems because it is caused by an age-related process. When people reach middle age (usually in the forties), nearby items start to appear blurry. People with presbyopia may struggle while working on a computer or find that they have to hold a menu at arm’s length in order to read it. Presbyopia affects everyone, even those who had perfect vision in the past. It is widely believed to be caused by a loss of flexibility in the lens of the eye. Treatment options for presbyopia include monovision, ck surgery, bifocals, progressive addition lenses, reading glasses, and multifocal lenses.

If you would like to find out more about treatment options for common visual problems or would like to arrange a thorough eye examination, please contact our laser eye surgery practice today.

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