@article{e252a19599a84d12a9b183fe949cb41a,
title = "Reflective multi-immersion microscope objectives inspired by the Schmidt telescope",
abstract = "Imaging large, cleared samples requires microscope objectives that combine a large field of view (FOV) with a long working distance (WD) and a high numerical aperture (NA). Ideally, such objectives should be compatible with a wide range of immersion media, which is challenging to achieve with conventional lens-based objective designs. Here we introduce the multi-immersion {\textquoteleft}Schmidt objective{\textquoteright} consisting of a spherical mirror and an aspherical correction plate as a solution to this problem. We demonstrate that a multi-photon variant of the Schmidt objective is compatible with all homogeneous immersion media and achieves an NA of 1.08 at a refractive index of 1.56, 1.1-mm FOV and 11-mm WD. We highlight its versatility by imaging cleared samples in various media ranging from air and water to benzyl alcohol/benzyl benzoate, dibenzyl ether and ethyl cinnamate and by imaging of neuronal activity in larval zebrafish in vivo. In principle, the concept can be extended to any imaging modality, including wide-field, confocal and light-sheet microscopy.",
keywords = "RESOLUTION, DESIGN, ORGANS, EYE",
author = "F.F. Voigt and A.M. Reuss and T. Naert and Sven Hildebrand and M. Schaettin and A.L. Hotz and L. Whitehead and A. Bahl and S.C.F. Neuhauss and Alard Roebroeck and E.T. Stoeckli and S.S. Lienkamp and A. Aguzzi and F. Helmchen",
note = "Funding Information: We would like to thank S. Giger for machining all custom objective parts, J. Kuhl for illustrations, D. Liittschwager for scallop photographs, B. Grewe for providing data acquisition hardware, U. Fuchs for optical design discussions, H. Kasper and M. Wieckhorst for technical assistance and S. Weidner for the design and production of 3D-printed parts. F.F.V. is supported by an HFSP fellowship (LT00687). T.N. received funding from H2020 Marie Sk{\l}odowska-Curie Actions (xenCAKUT - 891127). A.R. and S.H. were supported by a Dutch Science Foundation VIDI Grant (14637), and A.R. was additionally supported by an ERC Starting Grant (MULTICONNECT, 639938). In addition, this work was supported by the University Research Priority Program (URPP) {\textquoteleft}Adaptive Brain Circuits in Development and Learning (AdaBD){\textquoteright} of the University of Zurich (E.S. and F.H.); grants from the Swiss National Science Foundation (grant nos. 31003B-170269, 310030_192617 and CRSII5-18O316 to F.H. and 310030_189102 to S.S.L.); an ERC Starting Grant by the European Union{\textquoteright}s Horizon 2020 Research and Innovation Programme to S.S.L (grant agreement no. 804474, DiRECT); and the US Brain Initiative (1U01NS090475-01, F.H.). Publisher Copyright: {\textcopyright} 2023, The Author(s).",
year = "2024",
month = jan,
doi = "10.1038/s41587-023-01717-8",
language = "English",
volume = "42",
pages = "65--71",
journal = "Nature Biotechnology",
issn = "1087-0156",
publisher = "Nature Publishing Group",
number = "1",
}