Question

Define the following term in reference to a lens with a proper diagram:

Centre of curvature

Answer 1

Each curved surface of a lens is the part of a spherical surface. The centre of this sphere is called the centre of curvature. In the figure, C₁ and C₂ are the centres of curvature of the right and the left curved surfaces of the convex lens, respectively. In a concave lens, C₁ is on the left side and C₂ is on the right side of the surface.