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arXiv · 2302.14628

Dark-field light scattering microscope with focus stabilization

Anna Peters·Zhu Zhang·Sanli Faez
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Abstract

We present detailed design and operation instructions for a single-objective inverted microscope. Our design is suitable for two dark-field modes of operation: 1- total internal reflection scattering, and 2- cross-polarization backscattering. The user can switch between the two modes by exchanging one mode-steering element, which is also adapted to the Thorlabs cage system. To establish a stable background speckle for differential microscopy the imaging plane is stabilized with active feedback. We validate the stabilization efficacy by performing long-term scattering measurement on single nanoparticles. This setup can be extended for simultaneous scattering, fluorescence, and confocal imaging modes.

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Anna Peters, Zhu Zhang, Sanli Faez. 2023-02-15. Dark-field light scattering microscope with focus stabilization. https://arxiv.org/abs/2302.14628

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