A plano-convex lens of index has a curved face of radius magnitude mm
PHYSICS · Multi-part · Fermi University Physics · Optics & Photonics · Geometrical optics and imaging · Geometrical optics and imaging
Optics and Photonics, Ch Image formation by mirrors and lenses
Problem
A plano-convex lens of index n=1.50 has a curved face of radius magnitude 25 mm, a flat face, and an axial thickness tℓ=6.0 mm; it stands in air, light travelling left to right. Rays are paraxial. Use CV1 for the radii and CV2 for the matrices.
((a)) Curved face first. Write the two surface powers, build the vertex-to-vertex system matrix, and find the focal length and both principal planes, each measured from its nearer vertex.
((b)) Turn the lens round so the flat face meets the light first, and repeat. Which numbers change, which do not, and why?
((c)) A distant object is photographed with the lens in each orientation, the film being placed at the focus. By how much must the film move between the two orientations, measured from the back vertex of the glass?