Methods and systems for acquiring three-dimensional electron diffraction data

A system, comprising:

• an electron source for generating an electron beam along an optical axis;
• a sample holder for holding a sample and adjusting a sample position;
• a deflector for shifting the electron beam to irradiate different locations of the sample and tilting the electron beam to adjust an incident angle;
• a detector for detecting electrons transmitted through the sample;
• and
• a controller including a non-transitory memory for storing computer readable instructions, wherein by executing the computer readable instructions, the controller is configured to:
• acquire a sample image of the sample;
• select multiple crystals in the sample image;
• determine coordinates of the multiple selected crystals;
• direct the electron beam towards each of the multiple selected crystals, wherein at a location of each selected crystal, adjust the electron beam to acquire multiple diffraction patterns of the selected crystal at different incident angles, and the selected crystal is not rotated by the sample holder while the electron beam is directed towards the selected crystal;
• merge multiple diffraction patterns of the selected crystals into a diffraction dataset;
• and
• extract crystallographic information from the diffraction dataset.