A doctor has prescribed a corrective lens of power +1.5 D. Find the focal length of the lens. Is the prescribed lens diverging or converging ?

Power of lens, P= 1/f
P= 1.5D
f= \(\frac{1}{1.5 } = \frac{10}{15} = 0.66 m \)

A convex lens has a positive focal length. Hence, it is a convex lens or a converging lens.