Myopia can be corrected by using lens.

Question

Question

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KGMU Nursing Officer 2023 Memory-Based Previous Year Paper

Answer 1

Correct Answer: Concave lens

Rationale:

Myopia, also known as nearsightedness, is a common refractive error of the eye where distant objects appear blurry while nearby objects can be seen clearly. This occurs because the light entering the eye focuses in front of the retina instead of directly on it.
A concave lens is used to correct myopia as it diverges the incoming light rays before they enter the eye. This divergence shifts the focal point further back, allowing the light to focus directly on the retina and thus enabling clear vision of distant objects.
Concave lenses are prescribed based on the severity of myopia, measured in diopters. The stronger the myopia, the higher the power of the concave lens required.
These lenses are characterized by their thinner center and thicker edges, which create the diverging effect needed for correction.

Explanation of Other Options:

Convex lens

Rationale: Convex lenses converge light rays and are used to correct hyperopia (farsightedness), not myopia. Hyperopia occurs when the light focuses behind the retina, and the convex lens helps bring the focal point forward onto the retina.

Cylindrical lens

Rationale: Cylindrical lenses are used to correct astigmatism, a condition caused by irregular curvature of the cornea or lens. Unlike myopia or hyperopia, astigmatism affects vision clarity in all directions, and cylindrical lenses help focus the light correctly on the retina.

Plain lens

Rationale: A plain lens, also known as a plano lens, has no refractive power and does not alter the focus of light. It is typically used in protective eyewear or fashion glasses, not for correcting refractive errors like myopia.

Additional Information:

Myopia is often diagnosed during routine eye exams, and corrective lenses are the most common treatment. Other options include contact lenses, orthokeratology (special reshaping lenses worn overnight), or refractive surgery such as LASIK.
Lifestyle factors, such as prolonged screen usage and lack of outdoor activities, can contribute to the progression of myopia, especially in children. Preventive measures, such as regular breaks during close work and spending time outdoors, are recommended.

Conclusion:

Among the given options, concave lenses are the correct choice for correcting myopia as they address the underlying issue of light focusing in front of the retina. Other lens types serve different corrective purposes and are not suitable for treating nearsightedness.