We say that a particular person is suffering from hypermetropia, also known as farsightedness, when they have difficulty seeing objects up close. In hypermetropia, distant objects may be seen more clearly than nearby objects. This condition occurs when the eyeball is too short or the cornea is too flat, causing light rays entering the eye to focus behind the retina instead of directly on it.
Two causes of hypermetropia include:
- Short Eyeball: When the eyeball is shorter than normal, the image of nearby objects falls behind the retina instead of on it, leading to difficulty in focusing on close objects.
- Flat Cornea: A cornea that is too flat also results in the focal point falling behind the retina, causing distant objects to be in focus while nearby objects appear blurry.
To correct hypermetropia, a converging lens, also known as a convex lens, is used. This type of lens bends light rays inward and focuses them onto the retina, compensating for the eye's inability to do so.
