The Eye And Laser Eye Surgery Essay

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A Functioning Eye (Emmetropia)
The eye is the organ of sight. It is used in almost everything we do, from playing sport to reading. A normal and well functioning eye can focus objects and images, both near and far, perceive depth and adapt to changes in light.

The perception of depth is due to having two separate eyes creating two separate images, while the ability to adapt to light change is attributed to the iris and the dilator muscles. However these two aspects of the eye are not involved in laser eye surgery and will not be discussed in reference. The focusing of objects and images is very much part of laser eye surgery. In order for a clear visual image to be formed the image must come to a point on the retina. Light rays do not
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Refractive surgery is a term for several procedures designed to treat these vision abnormalities.

Eye Defects
Myopia - is the refractive condition where the farthest point of focus is located at a point near to the observer, and not at infinity. When one is nearsighted, distance vision is blurred at all times while near vision is often excellent within a certain range. There are a number of explanations for this optical condition. The eyeball may be too long, causing the image to be focused short of the retina at the back of the eye. Or, the focusing lenses of the eye are too strong.

The primary focusing lens is the cornea, the clear window at the very front of your eye. The internal lens, called the crystalline lens, is adjustable and alters your focus from distance to near. Sometimes, one of these two lenses may have a radius of curvature that is too steep. In myopia, it is often the cornea that is too highly curved. It is this curvature which is altered in laser eye surgery. Shortening the eyeball has been tried, but it has not been without the potential of serious and permanent damage. Often in situations where the crystalline lens is forced into an excessive plus power curvature, myopia can result. This may occur from near vision stress, a
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