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InterviewSolution
| 1. |
Explain myopia, hypermetropia, pressbiopia |
| Answer» Myopia\tNear-sightedness : A person with Myopia can see nearby objects clearly\tA person with myopia cannot see faraway objects clearly.\tThe far point for the myopic eye is nearer than infinity\tOccurs due to\tExcessive curvature of the eye lensElongation of eyeball\t\t\tThe image of a distance object is formed in front of the retina and not on the retina\tDefected is corrected by using Concave lenses such that the lens will bring the image back on to the retina.Hypermetropia\tFar sightedness : A person with Hypermetropia can see faraway objects clearly.\tA person with Hypermetropia cannot see nearby objects clearly.\tThe near point of the eye is more than 25cm\tThis arises mostly during latter stages in life, as a result of the weakening of the ciliary muscles and/or the decreased flexibility of the lens.Focal length of the eye lens is too longEyeball has become too small.\xa0\t\t\tThe image of a distance object is formed in behind the retina and not on the retina\tDefected is corrected by using Convex lenses such that the lens will bring the image back on to the retina.Presbyopia\tThe power of accommodation of the eye usually decreases with ageing. The ciliary muscles weaken and thereby the flexibility of the eye lens reduces.\tThe near point moves away.\tSpectacles with convex lenses are recommended | |