name the type of defeat of vision a person is suffering from , if he uses convex lenses in his spectacle for the correction of his vision ,if the power of the lenses is +0.50 , find the focal length og the lenses
Answers
The person using spectacles of convex lenses is suffering from
hypermetropja (farsightedness).
1. A person suffering from hypermetropja can see distant objects clearly as the image of a distant object is formed on the retina, but cannot see nearby objects clearly as the image of a nearby object would be formed behind the retina instead of on the retina.
2. A convex lens converges the rays of light passing through it.
3. When spectacles of convex lenses of appropriate power are used, the rays of light coming from a nearby object are converged to proper extent before they are incident on the eye lens.
Therefore, after the converging action of the eye lens, the image of a nearby object is formed on the retina of the eye and hence the nearby object can be seen clearly.
Hope it helps!