An observer holds in front of himself a thin equi convex lens. R is the radius of curvature of each face. He sees two images of his nose, one erect and the other inverted. Explain the formation of these images and assuming the refractive index of glass to be 1.50 prove that he will see two erect images if the distance of the lens is less than 0.25 R from his nose.

Answer

Reflection from the two surfaces results in formation of two images.