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bioRxiv · 10.1101/2024.08.15.607323

Sidelobe suppressed Bessel beams for one-photon light-sheet microscopy

Taneja, C.·George, J. G.·Corsetti, S.·Wijesinghe, P.·Bruce, G. D.·Zwart, M. F.·Bhattacharya, S.·Dholakia, K.
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Abstract

Bessel beams (BB) have found widespread adoption in various forms of light-sheet microscopy. However, for one-photon fluorescence, the transverse profile of the beam poses challenges due to the detrimental effect of the sidelobes. Here, we mitigate this issue by using a computer generated phase element for generating a sidelobe suppressed Bessel beam (SSBB). We then progress to perform a comparison of biological imaging using SSBB to standard BB in a light-sheet geometry. The SSBB peak intensity is more than an order of magnitude higher than the first sidelobe. In contrast to a standard BB light-sheet, SSBB does not need deconvolution and propagates to depths exceeding 400m in phantom samples maintaining a transverse size of 5 m. Finally, we demonstrate the advantage of using a SSBB light-sheet for biological applications by imaging fixed early-stage zebrafish larvae. In comparison to the standard BB, we observe a two-fold increase in contrast-to-noise ratio (CNR) when imaging the labelled cellular eye structures and the notochords. Our results provide an effective approach to generating and using SSBB light-sheets to enhance contrast for one-photon light-sheet microscopy.

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Taneja, C., George, J. G., Corsetti, S., Wijesinghe, P., Bruce, G. D., Zwart, M. F., Bhattacharya, S., Dholakia, K.. 2024-08-17. Sidelobe suppressed Bessel beams for one-photon light-sheet microscopy. https://doi.org/10.1101/2024.08.15.607323

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