Understanding Vision

Normal Vision

Light rays pass through the cornea to merge and focus perfectly on the back surface of the eye, called the retina, producing clear vision.

Nearsightedness - Myopia

Because the eye is longer than normal, light rays merge and focus before they reach the retina. The nearsighted eye sees close objects more clearly than distant objects.

Farsightedness - Hyperopia

Because the eye is shorter than normal, light rays reach the retina before merging and focusing. The farsighted eye sees distant objects more clearly, but may not see any object perfectly.

Astigmatism

Because the cornea is irregularly shaped, light rays focus at multiple points within the eye and distort vision. The astigmatic eye cannot focus clearly at any distance. Astigmatism often occurs in combination with near or farsightedness.

Presbyopia

In the natural processes of aging, the protein composition of the lens changes, making it harder and less flexible. The lens of the eye loses some of its elasticity and therefore its ability to change focus. Beginning sometime during our mid-forties, presbyopia diminishes close-range vision. This natural condition occurs even if LASIK has been performed to correct nearsightedness, farsightedness, or astigmatism.

Reading Glasses and Monovision

Presbyopia is a naturally occurring aging change that causes everyone to need bifocals or reading glasses usually around the age of 40-45. Having LASIK surgery does not cause presbyopia. Many nearsighted people can take off their glasses and see up close. If you have your nearsighted vision corrected for distance and are over age 40, you will no longer be able to see up close (3-4 feet) without reading glasses.

Monovision consists of leaving one eye somewhat nearsighted to allow for some close vision without glasses after age 40. Please inform us if you are interested in this option.