Cataract is the defect of vision which makes the eye-lens cloudy resulting in a blurred vision.
Name the eye defect in which eye lens becomes cloudy or milky. Mention the method for its correction. A person uses a lens of power -1.0 D for correcting his distant vision and for correcting his near vision he uses a lens of power + 2.0 D. Calculate the focal length of the lenses required to correct these defects. Explain why a normal eye is not able to see clearly the objects placed closer than the near points.
The following diagram represents a certain defect of vision of the human eye. Name the defect.