For a function to be piecewise continuous according to Dirichlet’s conditions, it must have only a finite number of extremities (maxima and minima) and discontinuities within any finite interval. This specifically excludes infinite discontinuities which would make the function not piecewise continuous.
In the diagram given below, there are three lenses formed. Considering negligible thickness of each of them as compared to \( R_1 \) and \( R_2 \), i.e., the radii of curvature for upper and lower surfaces of the glass lens, the power of the combination is: