Abstract: Improved aberration correction in multipass electron microscopy is provided by having Fourier images of the sample (instead of real images) at the reflection planes of the resonator. The resulting ?1 magnification of the sample reimaging can be compensated by appropriate sample placement or by adding compensating elements to the resonator. This enables simultaneous correction of lowest order chromatic and spherical aberration from the electron objective lenses. If real images of the sample are at the reflection planes of the resonator instead, only the lowest order chromatic aberration can be corrected.

Abstract: An electron beam phase plate is provided where patterned radiation is provided to the phase plate to creates a corresponding electrical pattern, This electrical pattern provides a corresponding patterned modulation of the electron beam. Such modulation can be done in transmission or in reflection. This approach has numerous applications in electron microscopy, such as providing phase and/or amplitude shaping, aberration correction and providing phase contrast.

Abstract: Improved aberration correction in multipass electron microscopy is provided by having Fourier images of the sample (instead of real images) at the reflection planes of the resonator. The resulting ?1 magnification of the sample reimaging can be compensated by appropriate sample placement or by adding compensating elements to the resonator. This enables simultaneous correction of lowest order chromatic and spherical aberration from the electron objective lenses. If real images of the sample are at the reflection planes of the resonator instead, only the lowest order chromatic aberration can be corrected.