- Retina – Light sensitive screen at the back of the eye.
- Optic Nerve – Carries information in electrical form to the brain.
- Cornea – Together with the lens, it forms part of the focusing system.
- Iris – Acts like a shutter, controls the amount of light entering.
- Ciliary Muscle – Changes the shape of the lens.
Power of Accommodation
Long Sightedness – Hypermetropia
- Distant objects are seen clearly.
- Near objects are focused beyond the retina.
- Convex (converging) lens.
Short Sightedness – Myopia
- Near objects are seen clearly.
- Distant objects are focused before the retina.
- Concave (diverging) Lens.