What Causes Hyperopia (Farsightedness)?

Hyperopia (also called Hypermetropia or Farsightedness / Duur Drishti Dosh) is a common eye defect in which a person can see distant objects clearly but nearby objects appear blurred. It is the opposite of Myopia (Nearsightedness).

Question (Click to Flip)

What is the difference between hyperopia and myopia?

Answer

In Myopia (Nearsightedness), the image forms in FRONT of the retina — near objects are clear, far objects are blurred. Corrected with concave (negative) lenses. In Hyperopia (Farsightedness), the image forms BEHIND the retina — far objects are clear, near objects are blurred. Corrected with convex (positive) lenses.

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Key Facts

Presbyopia is a special case of hyperopia that affects almost everyone after age 40-45. The word comes from the Greek word presbys meaning 'old man'. People with presbyopia often use reading glasses.

Causes of Hyperopia

Hyperopia occurs because the image of a nearby object forms behind the retina instead of exactly on it. This happens due to:

Decreased power of the eye lens: The eye lens becomes too flat (less curved) and cannot converge rays from nearby objects sufficiently.
Shortened eyeball: If the eyeball is shorter than normal (front to back), the retina is too close to the lens, so the focal point falls behind the retina.
Age-related (Presbyopia): With age, the lens loses its flexibility and can no longer accommodate (change shape) to focus on near objects. This is the most common cause in adults over 40.

Correction of Hyperopia

Hyperopia is corrected using Convex Lenses (Converging Lenses) (positive power glasses or contact lenses).

A convex lens converges the incoming light rays before they enter the eye, effectively helping the eye lens focus the image exactly on the retina instead of behind it.

Prescription: A hyperopic person's spectacle prescription will have a positive (+) power (e.g., +1.5D, +2.0D).

Questions and Answers

What is the difference between hyperopia and myopia?+

In **Myopia (Nearsightedness)**, the image forms in FRONT of the retina — near objects are clear, far objects are blurred. Corrected with **concave (negative) lenses**. In **Hyperopia (Farsightedness)**, the image forms BEHIND the retina — far objects are clear, near objects are blurred. Corrected with **convex (positive) lenses**.

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