Myopia (shortsightedness)
Having this defect means clear vision for near objects but images of distant objects are formed in front of the retina. The cause of the defect is the eyeball being too long or shorter focal length. The defect is corrected by using a diverging lens of appropriate focal length so that the rays reaching the eye lens appear as if they are coming from a near object.
Hypermetropia (long-sightedness)
A person who is long-sighted has clear vision of distant objects but cannot see clearly closer objects clearly. It is caused by the eyeball being too short or longer focal length so that the image of a closer object is formed behind the retina. The defect is corrected by using a converging lens of appropriate focal length.
Moraa orina answered the question on August 14, 2018 at 17:07
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