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Updated: Aug 12, 2026
08:04
Preparation and Observation of Thick Biological Samples by Scanning Transmission Electron Tomography
Published on: March 12, 2017
An improved scanning method based on characteristics of the human visual system for scanning electron microscopy
Eisaku Oho1, Takayoshi Sugawara, Kazuhiko Suzuki
1Department of Electrical Engineering, Kogakuin University, Tokyo, Japan. oho@cc.kogakuin.ac.jp
Scanning
|August 11, 2005
Summary
A new quincuncial scanning method improves scanning electron microscope (SEM) image quality under rough sampling. This technique enables faster image acquisition for SEM snapshots.
Area of Science:
- Microscopy and Imaging Technologies
- Image Processing and Analysis
Background:
- Conventional raster scanning in Scanning Electron Microscopy (SEM) can limit image quality under undersampling conditions.
- The human visual system exhibits lower sensitivity to diagonal patterns, a characteristic leveraged in this study.
Purpose of the Study:
- To introduce and evaluate an improved SEM scanning method using quincuncial sampling.
- To enhance SEM image quality, particularly under undersampling conditions.
- To enable faster SEM image acquisition for 'snapshot' mode applications.
Main Methods:
- Implementation of quincuncial scanning (sampling) as an alternative to conventional raster scanning.
- Utilizing high-precision interpolation techniques to reconstruct images.
- Analysis of image quality improvements and recording time reductions.
Main Results:
- Quincuncial scanning significantly improves SEM image quality when undersampling.
- The method requires doubling the number of pixels for optimal results, beneficial for printing.
- SEM image acquisition time is substantially reduced, facilitating rapid recordings.
Conclusions:
- Quincuncial scanning offers a viable method for enhancing SEM image quality and speed.
- This technique addresses limitations of undersampling and enables practical 'snapshot' SEM imaging.
- The method is advantageous for applications requiring frequent, quick SEM recordings.
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