Name the type of lens used to correct eye defect.

Given below is a diagram depicting a defect of the human eye, study the same and then answer the questions that follow: (i) Name the defect shown in the diagram. (ii) What are the two possible reasons that cause this defect? (iii) Name the type of lens used to correct this defect. (iv) With the help of a diagram show how the defect shown above is rectified using a suitable lens.

Study the diagram given below and answer the questions which follow. The diagram is depicting a defect of the human eye. Name the type of lens used to correct short sightedness.

We can burn a piece of paper by focusing the sun rays by using a particular type of lens. Name the type of lens used for the above purpose.

What type of lens is used to correct long sightedness ?

Make a diagram to show how hypermetropia is corrected. The near point of a hypermetropic eye is 1 metre . What is the power of the lens required to correct this defect ? Assume that the near point of the normal eye is 25 cm .

The lens used for correcting myopia is.

Due to gradual weakening of ciliary muscles and diminishing flexibility of the eye lens, a certain defect of vision arises. Write the name of this defect. Name the type of lens required by such persons to improve the vision. Explain the structure and function of such a lens.

A person is unable to see objects distinctly placed within 50 cm from his eyes. (a) Name the defect of vision the person is suffering from and list its two possible causes. (b) Draw ray diagram to show the defect in the above case. (c) Mention the type of lens used by him for the correction of the defect and calculate its power. Assume that the near point for the normal eye is 25 cm. (d) Draw a labelled diagram for the correction of the defect in the above case.

Which type of lens is used to correct astigmatisum ?

Which of the following type of lens is used to correct the vision of a near sighted individual ?