Generation of Bessel-like beams with reduced sidelobes for enhanced light-sheet microscopy

The authors acknowledge financial support from the Ministry of Human Resource Development, New Delhi through the SPARC project. KD acknowledges support from the Australian Research Council and the European Union’s Horizon 2020 research and innovation programme under the H2020 FETOPEN project “Dynamic”.Bessel beams have found important applications due to their propagation invariant nature. However, the presence of sidelobes has proven a hindrance in key imaging and biophotonics applications. We describe the design and generation of sidelobe-suppressed Bessel-like beams (SSBB) that provide enhanced contrast for light-sheet imaging. The sidelobe suppression is achieved by the interference of two Bessel beams with slightly different wavevectors. Axicon phase functions for each Bessel beam are combined into a single phase function using the random multiplexing technique. This phase function is realised using a spatial light modulator to generate a SSBB. The generated beam at 633 nm has a 1/e2 radius of 44 µm and a propagation invariant distance of 39 mm which is more than four times that of the Rayleigh range of a Gaussian beam with the same 1/e2 radius. Within this distance, the overall peak intensity of the sidelobes of the SSBB is less than 10% that of the main lobe peak intensity. In addition, through numerical simulation for the recovery of spatial frequencies, we show that the SSBB improves image contrast compared to a Bessel beam for light-sheet imaging. We also show that the designed phase function can be realised using a meta-optical element.Publisher PDFPeer reviewe