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What is Lens used in Astigmatism: and explain in detail?
Ans. (b) CylindricalRef: A.K. Khurana 6th ed. 142-423* Astigmatism is a common eye condition that's easily corrected by eyeglasses, contact lenses, or surgery.* It is caused by an eye that is not completely round. It is a type of refractive error.* Cause: Astigmatism is a natural and commonly occurring cause of blurred or distorted vision. The exact cause in not known.* Symptom: Blurring of vision which can be associated with fatigue and eyestrain.*The cylindrical lens is used for the management of astigmatism.Also, Know* Myopics are said to be short-sighted. Concave lenses are used in myopics* A convex lens is used in hypermetropic.