In the human eye,the image of an object is formed on the $................$.

$A$ near-sighted person can see only nearer objects.

$A$ person suffering from an eye defect uses lenses of power $-1 \,D$. Identify the eye defect. Draw a suitable diagram to illustrate how this type of lens corrects the defect. Give the nature of the corrective lens to be used. Also,calculate the focal length of the corrective lens.

Name the essential parts of the human eye.

What is another name for the defect of myopia?

What color of light is produced when blue and yellow light are superimposed?