Quasi-non-diffracting static light sheets generated by holistically optimized pupil masks

Sidelobe-suppressed sub-diffraction-limit quasi-non-diffracting light sheets achieved by super-oscillatory lenses

Sub-diffraction-limit quasi-non-diffracting light sheets (SQLSs) are crucial for a resolution-enhanced and field of view (FOV)-enlarged light sheet microscope. However, it has aways been plagued by sidelobes inducing severe background noise. Here, a self-trade-off optimized method is proposed to generate sidelobe-suppressed SQLSs based on super-oscillatory lenses (SOLs). An SQLS thus obtained shows sidelobes of only 15.4%, first realizing the sub-diffraction-limit thickness, quasi-non-diffracting characteristic, and suppressed sidelobes simultaneously for static light sheets. Moreover, a window-like energy allocation is realized by the self-trade-off optimized method, successfully further suppressing the sidelobes. In particular, an SQLS with theoretical sidelobes of 7.6% is achieved within the window, which provides a new strategy to deal with sidelobes for light sheets and shows great potential in high signal-to-noise ratio light sheet microscopy (LSM).

Sub-diffraction-limit light sheet enabled by a super-oscillatory lens with an enlarged field of view and depth of focus

Static light sheets are widely used in various super-resolution three-dimensional (3D) imaging applications. Here, a multifocal diffraction-free optimized design method is proposed for super-oscillatory lenses (SOLs) owning an enlarged field of view (FOV) to generate sub-diffraction-limit light sheets with reduced divergence. Various propagation lengths of sub-diffraction-limit thickness for light sheets can be obtained by adopting corresponding numbers of discrete foci and spacing between them. In particular, the propagation lengths of 150.4λ and 118.9λ are obtained by SOLs with an enlarged FOV of 150λ and 820λ, respectively, which show the longest depth of focus (DOF), as far as we know, and are the first to realize the combination of enlarged DOF and FOV for SOLs. We show a way of using binary-amplitude modulation to generate static light sheets with sub-diffraction-limit thickness and reduced divergence, which is simple, easy to integrate, and sidelobe-suppressed.