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Dynamic Scan Shaping: Overcoming Coil Hysteresis for High-Speed STEM
Jonathan J P Peters1,2, Grigore Moldovan3, Lewys Jones1,2
1Advanced Microscopy Laboratory, CRANN, Trinity College Dublin, the University of Dublin.
Microscopy (Oxford, England)
|May 12, 2026
Summary
Researchers developed a predictive scan shaping method to overcome slow imaging speeds in scanning transmission electron microscopy (STEM). This advance enables faster, clearer dynamic event capture in materials science research.
Area of Science:
- Materials Science
- Physics
- Microscopy
Background:
- Scanning transmission electron microscopy (STEM) offers advanced imaging and spectroscopy capabilities.
- Conventional STEM suffers from slow imaging speeds (a few frames per second) due to sequential pixel acquisition.
- Slow speeds limit dose-rate control, increase distortions, and hinder in-situ dynamic event capture.
Purpose of the Study:
- To address the limitations of slow imaging speeds in STEM.
- To develop a method for faster STEM imaging without new hardware.
- To improve the ability to capture dynamic events during in-situ experiments.
Main Methods:
- Implemented a predictive scan shaping approach for conventional scanning systems.
- Scan input was determined based on predicted beam position rather than current position.
- Acquired fully sampled 512x512 images with a pixel dwell time of 60 nanoseconds.
Main Results:
- Achieved significantly faster imaging framerates.
- Demonstrated a framerate of 41 frames per second for 512x512 images.
- Overcame limitations imposed by scanning coil inductance and hysteresis.
Conclusions:
- Predictive scan shaping is an effective method to increase STEM imaging speed.
- This technique enhances the potential for capturing dynamic processes in materials.
- The approach offers a hardware-independent solution to a long-standing STEM challenge.
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