Principles of electron structure research at atomic resolution using conventional electron microscopes for the measurement of amplitudes and phases

An electron microscope equipped with conventional electron optics can be used as a `diffractometer' for structure research on individual aperiodic objects. The resolution limit of the electron microscope is not the resolution limit of the `diffractometer' and electron structure research with atomic resolution is possible. The advantage is that a diffractometer of this type can measure amplitudes and phases. The theory is developed in the language of the crystallographer, mainly using the concept of modifying functions. It is shown that, as in crystallography, redundancies in structures can be used in the analysis.