Myopia (near-sightedness) and its correctionनिकट-दृष्टि दोष और उसका संशोधन

NCERT Fig 10.2 · interactive diagram

Parts and their functions

• Far point O of a myopic eye (निकट-दृष्टि दोषयुक्त नेत्र का दूर बिंदु O) — Nearer than infinity. Objects up to O are seen clearly.
• Image of a distant object forms in front of the retina (दूर की वस्तु का प्रतिबिंब दृष्टिपटल के आगे) — Cause: excessive curvature of the eye lens, or elongation of the eyeball.
• Corrected eye (संशोधित नेत्र) — The diverging lens makes parallel rays appear to come from the far point O, so the image falls on the retina.
• Concave lens of suitable power (उपयुक्त क्षमता का अवतल लेंस) — Focal length = − (distance of the far point). e.g. far point 80 cm → f = −80 cm, P = −1.25 D.

Original diagram drawn by Simple Learning Hub, based on NCERT Fig 10.2. Report a mistake