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Essay On Human Eye

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Essay On Human Eye
In this research paper, I am going to talk about many different subtopics surrounding the human eye, such as how an eye works and some of the diseases and conditions that affect someone’s vision. I also want to find out if myopia (near-sightedness) disappears by adulthood, considering my brother has just been diagnosed with it. Plus, I am curious to see if there is some type of cure for blindness, considering how many people it must affect. First, let me explain how the human eyeball works!

The human eye works like a camera. The cornea acts like the window of the eye; when light enters through the cornea, the light rays bend in a way that they pass freely through the pupil. The cornea is also where most of the focusing in the eye occurs. The
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Astigmatism is usually caused by an irregularly shaped cornea, which most often in the shape of a football instead of a sphere. This causes light to fail meeting at a single point on the retina, and instead creates multiple focus points that fall short of the retina, or in behind it. Uncorrected astigmatism can cause eyestrain and headaches, especially after reading, and blurred and distorted vision to a certain degree. There are three types of astigmatism: myopic astigmatism, hyperopic astigmatism, and mixed astigmatism. Myopic astigmatism causes one or both of the principal meridians (the two imaginary lines, one vertical and one horizontal, that intersect at the middle of the eye) to become near-sighted. Hyperopic astigmatism is the exact opposite; it causes one or both of the principal meridians to become far-sighted, and mixed astigmatism is the mixture of both myopic and hyperopic astigmatism. Treatment options include eyeglasses, contact lenses, and refractive surgery. Astigmatism usually occurs early in life, so it is suggested to have children checked by an optometrist

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