Question

Name three refractive defects of vision with help of diagram. Explain its reasons and correction of these defects. ?

Answer 1

(a) List three common refractive defects of vision. Suggest the way of correcting these defects. (b) About 45 lac people in the developing countries are suffering from corneal blindness. About 30 lac children below the age of 12 years suffering from this defect can be cured by replacing the defective cornea with the cornea of a donated eye. How and why can students of your age involve themselves to create awareness about this fact among people?

Ask for details Follow Report by Radzkarankaarchitt 10.02.2016

Answers

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bjahnavi

bjahnavi Ace

The 3 common defects are :-

# ) Myopia

# ) Hypermetropia

# ) Presbyopia.

Corrections:-

#) Myopia- Concave Lens

#) Hypermetropia - Convex lens

#) Presbyopia - Bifocal lens of corrective focal length.

By having Awareness classes or by programmes.

By printing a pamphlet

By making posters

Thank you.....!!!!

Mark as brainliest of helpful..

Answer 2

There are three 'refractive defects of vision'.

• Myopia: (Near sightedness) in which people are unable to see far objects.

• Hypermetropia:  (Far sightedness) in which people are unable to see nearby objects.

• Presbyopia: The eye sight becomes weak due to aging.

Explanation:

Myopia occurs when your "eyeball is longer" than normal or cornea is 'curved' too steeply. Instead of focusing light on retina, light is focused in front of the retina, resulting in blur image. It can be corrected with concave lens.

Hypermetropia occurs when your "eyeball is shorter" than normal or cornea is 'curved' too little. It can be corrected with the help of convex lens.

Presbyopia occurs due to weakening of eyes muscles and eye lens becomes rigid. It can be corrected with the help of bifocal lens.