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A cylindrical lens is used by a person suffering from astigmatism. Astigmatism is a common vision condition that causes blurred or distorted vision. It occurs when the curvature of the cornea or lens is uneven, causing light to focus on multiple points on the retina instead of one clear point.
A cylindrical lens is specifically designed to correct this uneven curvature by providing different refractive powers in different meridians. It has a cylindrical shape, with one surface curved more than the other. This shape allows the lens to bend the light in one direction more than the other, compensating for the uneven curvature of the eye.
The other options listed in the question are different vision conditions that require different types of corrective lenses:
- Myopia, also known as nearsightedness, is corrected with concave lenses that diverge light before it reaches the eye.
- Hypermetropia, also known as farsightedness, is corrected with convex lenses that converge light before it reaches the eye.
- Presbyopia, which is an age-related loss of near vision, is corrected with multifocal lenses or reading glasses.
Therefore, the correct answer is option 1: Astigmatism.