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arXiv · 1811.11457

Diffraction-limited axial scanning in thick biological tissue employing an aberration correcting adaptive lens

Katrin Philipp·Florian Lemke·Stefan Scholz·Ulrike Wallrabe·Matthias C. Wapler·Nektarios Koukourakis·Jürgen W. Czarske
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Abstract

Diffraction-limited focusing deep into biological tissue is challenging due to spherical aberrations that lead to a broadening of the focal spot particularly in axial direction. While the diffraction-limit can be restored employing aberration correction with a deformable mirror or spatial light modulator, a bulky optical setup results due to the required beam-folding. We propose a bi actor adaptive lens, that enables axial scanning and at the same time correction of specimen induced spherical aberrations while offering a compact setup. Using the bi-actor lens in a confocal microscope, we show diffraction limited axial scanning up to \SI{340}{\micro m} deep inside a phantom specimen. Applying this technique for in-vivo measurements of zebrafish embryos with reporter gene-driven fluorescence in the thyroid gland reveals substructures of thyroid follicles.

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Katrin Philipp, Florian Lemke, Stefan Scholz, Ulrike Wallrabe, Matthias C. Wapler, Nektarios Koukourakis, Jürgen W. Czarske. 2018-11-28. Diffraction-limited axial scanning in thick biological tissue employing an aberration correcting adaptive lens. https://doi.org/10.1038/s41598-019-45993-4

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