Physics - Geometrical Optics Question with Solution | TestHub

Spherical aberration of a plano-convex lens is minimised by sharing the total deviation between the two refracting surfaces (A), by using a coaxial aperture stop so only the central paraxial portion is used (B), and by keeping the convex surface toward the parallel (incident or emergent) beam so the deviation is distributed (C). Turning the curved surface perpendicular to the principal axis (D) does not minimise it. Hence (A), (B), (C).