A lens system is proposed that not only provides spherical correction of the objective lens by charges that are induced on a thin foil, in the way proposed in a paper by Otto Scherzer [Optik56(2), 133–147, 1980], but also provides Zernike phase contrast by means of an appropriate phase shift of the scattered electrons within the foil. This system has the potential to provide strong phase contrast from very low spatial frequencies to frequencies above 1/(100 pm).