Confocal microscopy provides optical sectioning that is invaluable for many applications, most notably imaging into thick samples. However, the high cost of commercial confocal microscopes limits uses to specialized research and clinical settings. We present a minimalistic line-scanning confocal microscope costing less than $6,500 with optical performance comparable to a commercial laser scanning system. The optical sectioning and imaging performance are shown through measurement of the axial line-spread function and imaging of biological samples of varying thickness. Comparison is made to commercial widefield and confocal microscopes. The low cost of goods and optical sectioning capability of this microscope will allow the use of confocal microscopy in additional research and educational settings.
Confocal microscopy is an indispensable tool for biological imaging due to its high resolution and optical sectioning capability. However, its slow imaging speed and severe photobleaching have largely prevented further applications. Here, we present dual inclined beam line‐scanning (LS) confocal microscopy. The reduced excitation intensity of our imaging method enabled a 2‐fold longer observation time of fluorescence compared to traditional LS microscopy while maintaining a good sectioning capability and single‐molecule sensitivity. We characterized the performance of our method and applied it to subcellular imaging and three‐dimensional single‐molecule RNA imaging in mammalian cells.
- Award ID(s):
- 1805200
- NSF-PAR ID:
- 10452496
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Journal of Biophotonics
- Volume:
- 12
- Issue:
- 10
- ISSN:
- 1864-063X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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