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Point scanning imaging systems (e.g. scanning electron or laser scanning confocal microscopes) are perhaps the most widely used tools for high resolution cellular and tissue imaging. Like all other imaging modalities, the resolution, speed, sample preservation, and signal-to-noise ratio (SNR) of point scanning systems are difficult to optimize simultaneously. In particular, point scanning systems are uniquely constrained by an inverse relationship between imaging speed and pixel resolution. Here we show these limitations can be miti gated via the use of deep learning-based super-sampling of undersampled images acquired on a point-scanning system, which we termed point -scanning super-resolution (PSSR) imaging. Oversampled ground truth images acquired on scanning electron or Airyscan laser scanning confocal microscopes were used to generate semi-synthetictrain ing data for PSSR models that were then used to restore undersampled images. Remarkably, our EM PSSR model was able to restore undersampled images acquired with different optics, detectors, samples, or sample preparation methods in other labs . PSSR enabled previously unattainable xy resolution images with our serial block face scanning electron microscope system. For fluorescence, we show that undersampled confocal images combined with a multiframe PSSR model trained on Airyscan timelapses facilitates Airyscan-equivalent spati al resolution and SNR with ~100x lower laser dose and 16x higher frame rates than corresponding high-resolution acquisitions. In conclusion, PSSR facilitates point-scanning image acquisition with otherwise unattainable resolution, speed, and sensitivity.
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LBIC Imaging of Solar Cells: An Introduction to Scanning Probe-Based Imaging Techniques
Scanning probe-based microscopes (SPMs) are widely used in biology, chemistry, materials science, and physics to image and manipulate matter on the nanoscale. Unfortunately, high school and university departments lack expensive SPM tools and materials microscopy activities to educate a large number of students in this vital SPM imaging technique. As a result, students face challenges participating in and contributing value to the nanotechnology revolution driving modern scientific innovations. Here we demonstrate an affordable scanning laser-based imaging system (approximately $400, excluding the computer) to introduce students to the point-by-point image formation process underlying SPM methods. In this laboratory activity, students learn how to construct and optimize images of a working solar panel using a laser beam-induced current (LBIC) imaging system. We envision undergraduate and graduate students should be able to use this LBIC system for independent solar energy research projects as well as apply fundamental knowledge and measurement skills to understand other SPM techniques.
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- Award ID(s):
- 2046948
- PAR ID:
- 10394417
- Date Published:
- Journal Name:
- Journal of Chemical Education
- ISSN:
- 0021-9584
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1021/acs.jchemed.2c00623
