The Human Eye and the Colourful World · medium

Hypermetropia (Far-sightedness)

Your eye focuses nearby objects behind the retina — so close-up things blur while distant ones stay clear.

nerveirislenscornearetinafocus(behind retina)

Rays are still converging when they reach the retina — the focus point lies behind it.

Hypermetropia is the opposite problem to myopia. Here the eyeball is a bit too short, or the lens is too weakly curved (focal length too long) — so light from nearby objects focuses at a point behind the retina instead of on it.

A person with this defect has to hold reading material well beyond the normal 25 cm to see it clearly, because their near point has shifted farther away than normal.

The fix: a convex (converging) lens adds extra focusing power, bending the light rays inward a bit more before they enter the eye, so they now converge exactly on the retina instead of behind it.

  • Near point is farther than the normal 25 cm
  • Caused by: (i) eyeball too small, or (ii) focal length of eye lens too long
  • Image of a nearby object forms behind the retina
  • Corrected using a convex lens of suitable (positive) power

Difference between Myopia and Hypermetropia — Class 10 · Class 10 Science

← back to search