Three tools for an automated analysis of electron diffraction pattern and crystallographic visualization are presented. Firstly,diffractGUIdetermines the zone axis from selected area diffraction, convergent beam diffraction or nanodiffraction patterns and allows for indexing of individual reflections. Secondly,ringGUIidentifies crystallographic planes corresponding to the depicted rings in the ring diffraction pattern and can select the sample material from a list of candidates. BothdiffractGUIandringGUIemploy methods of computer vision for a fast, robust and accurate analysis. Thirdly,cellVieweris an intuitive visualization tool which is also helpful for crystallographic calculations or educational purposes.diffractGUIandcellViewercan be used together during a transmission electron microscopy session to determine the sample holder tilts required to reach a desired zone axis. All the tools offer a graphical user interface. The toolbox is distributed as a standalone application, so it can be installed on the microscope computer and launched directly fromDigitalMicrograph(Gatan Inc.).

A new release of the CrysTBox software is introduced. The original toolbox allows for an automated analysis of transmission electron microscope (TEM) images and for crystallographic visualization. The existing tools, which are capable of highly precise analyses of high‐resolution TEM images, as well as spot, disc and ring diffraction patterns, are extended to include a tool for automatically measuring TEM sample thickness using convergent beam electron diffraction in a two‐beam approximation. An implementation of geometric phase analysis is newly available, employing one of the existing tools to identify parameters and indices of crystallographic planes depicted in the input image and allowing easier and more accurate analysis. The crystallographic visualization capabilities are extended as well. Along with the simulated diffraction pattern and atomic structure, a stereographic projection and inverse pole figure tool is newly offered. A new tool able to visualize the atomic structure of two different phases and their interface is also introduced.

A method for quantifying inhomogeneity of crystal structure at the nanoscale is suggested and experimentally verified. The method is based on digital processing of images obtained by high-resolution transmission electron microscopy. A series of images is acquired and each image is divided into several overlapping sliding windows. Interplanar distances are determined using a fast Fourier transform and the CrysTBox software. A spatial distribution of the estimated distances is obtained considering the size and position of the sliding window within the analysed sample. This approach provides for a picometric precision and accuracy if applied on ideal data. Although this accuracy was verified on experimental data, it can be worsened by errors specific to a particular application and data acquisition technique. The achieved spatial resolution ranges from a few to tens of nanometres. These levels of accuracy, precision and spatial resolution are reached without the need for aberration correction or for a reference lattice parameter, and using samples prepared by focused ion beam milling.

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