Astigmatism is a condition where there is asymmetric blur of an object. In an astigmatic eye, one direction of the image may be focused on the retina and part in front or behind the retina. Astigmatism is usually due to the shape of the front of the eye, the cornea, not being completely spherical. This results in light which would normally be focused as a point on the retina, being focused as a line. To focus the image on the retina, a cylindrical spectacle lens is required to be placed in front of the eye. This will make objects at any distance clear.



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