Properties of electron round lenses produced by the ponderomotive potential are investigated in geometrical optics. An electron convex lens and a third-order spherical aberration corrector are provided by a potential proportional to the intensity distribution of a focused first-order Bessel or Laguerre-Gaussian beam. Several formulas for the focal length and aberration coefficients in the thin lens approximation enable the design of lens properties and associated optical beam parameters. When

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... e optical beam's mode field is small, the results of electron trajectory calculations show properties that are similar to those given by the formulas, whereas large higher-order aberrations are introduced because of the annular distribution of the potential. The Bessel and Laguerre-Gaussian beams of second- and higher-order produce no focusing power and no negative third-order spherical aberration. However, they would be still promising for use as circularly symmetric higher-order aberration correctors. According to the findings, an electron lens or phase plate based on the ponderomotive potential forms a refractive index medium with a much more flexible shape than conventional electrostatic and magnetic electron optics. The formulas presented in this article can serve as guidelines for designing preferred light fields, resulting in the advancement of novel technology in electron optics that makes use of the electron-light interaction.