New foundational technology for scanning transmission electron microscopy developed by the Institute of Science Tokyo, JEOL, and others

A research team led by Professor Takumi Sannomiya of the Department of Materials Science and Engineering at the Institute of Science Tokyo, Dr. Akira Yasuhara of JEOL Ltd., and Professor Ryoichi Horisaki of the Graduate School of Information Science and Technology at the University of Tokyo has successfully reconstructed high-resolution images using fewer scan pixels by employing a multi-beam method in a scanning transmission electron microscope (STEM) that simultaneously generates multiple beams. It is expected to become a new fundamental technology for faster and lower dose electron microscopy measurements. The results were published in Ultramicroscopy.

In conventional STEM, acquisition speed is slow due to scanning one point at a time, and the electron beam damages the sample, limiting the measurement target. The research group has developed a new scanning transmission electron microscopy technique that combines multi-beam irradiation, which generates multiple electron beams simultaneously, with image reconstruction based on compressive sensing.

In this method, they formed a multi-beam probe using an aperture with multiple randomly distributed holes and adjusted the beam distribution through defocus control. While providing structured illumination on the sample, they acquired data through sparse sampling. The resulting signal is observed as a low-resolution multiplexed image of overlapping multi-beams. However, by utilizing the probe shape and reconstructing the signal as an optimization problem that includes total variation normalization, they demonstrated that high-fidelity images can be restored.

In experiments, they successfully reconstructed images of gold nanoparticles, even with sampling densities as low as 1/4 to 1/10 of the original level.

Since this method is based on bucket detection, which measures only the total amount of the signal without spatially resolving the detection signal, it can be applied not only to structural imaging but also to various types of analytical mapping. This demonstrates the possibility of significantly easing the trade-offs between high resolution, high speed, and low dose in electron microscopy observations.

Journal Information
Publication: Ultramicroscopy
Title: Compressive multi-beam scanning transmission electron microscopy
DOI: 10.1016/j.ultramic.2026.114353