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Correcting Vision Problems Using Lenses

Refractive errors are common vision problems affecting the ability to focus on objects at varying distances. Hyperopia (farsightedness) occurs when an eyeball is too short, causing difficulty in viewing nearby objects. Myopia (nearsightedness) arises from an elongated eyeball, leading to blurred distance vision. Astigmatism results from an irregularly shaped cornea, causing distorted vision in multiple directions. These conditions can be corrected using lenses: convex for hyperopia and concave for myopia, while astigmatism may require varying prescriptions across different axes.

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Correcting Vision Problems Using Lenses

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  1. Correcting Vision Problems Using Lenses Light and Geometric Optics

  2. Refractive Errors – Hyperopia(Far- Sightedness) • those who are farsighted have difficulty focusing on distant objects and are even blurrier up close; • caused by an eyeball that is too short, and a cornea that is too flat • light rays from nearby object diverge more strongly than the ones from faraway objects; • the light rays focus at a point behind the retina; • can be corrected using convex lenses

  3. Refractive Errors - Myopia (Nearsightedness) • - individuals can see objects that are close clearly, but cannot see far away; • happens when light rays focus in front of the retina; • caused by an eyeball that is too long, and a cornea with too much curvature (i.e., too much focusing power); • corrected by concave lenses; • - diverging lenses cause the light from distant objects to diverge as they approach the eye.

  4. Refractive Errors - Astigmatism • occurs along with nearsightedness or farsightedness; • due to a cornea that has an irregular shape • light entering the eye from different directions is focused different amounts; • or example, light entering vertically may be focused more than light entering horizontally; • light is focused the same amount in each axis  blurred vision; • letters appear slanted or have tails, and the affected eye sees double; • astigmatism is treated similarly to nearsightedness and farsightedness, but with different amounts of treatment on each axis.

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