Multiplane Illumination Enabled by Fourier-Transform Metasurfaces for High-Speed Light-Sheet Microscopy

Light-sheet fluorescence microscopy has made a substantial imprint in the development of cell biology, anatomical sciences and neurosciences with its superior performance of high-speed three-dimensional imaging acquisition at high resolution. However, its implementation requires delicate instrumentation, and further extension of its present capability seems limited by current optics systems and techniques. Metasurfaces are presently receiving increased attention for its versatile capacity in constructing multifunctional photonic components with low dimension and high efficiency. Here, we propose and design a dielectric metasurface to realize convenient multiple light-sheet illumination. In mathematics, ideal periodic multiple light sheets are the Fourier transform of a series of coherent light waves with discrete angular spatial frequencies, which can be easily generated by the sophisticatedly designed compact yet efficient metasurface. Full-wave simulations demonstrate that the diffraction pattern, produced by the metasurface, has extremely large interval and nearly half-wavelength thickness in the direction perpendicular to light propagation. This consequently allows for the realization of multiple light sheets with time-averaged uniform intensity by mechanically dithering the metasurface in the propagation direction. We finally show that the inevitable background noise dressed in the diffraction pattern can be effectively suppressed by adopting two-photon excitation. This study provides a practicable means to produce multiple light sheets potentially for building high-speed, high-resolution light-sheet microscopy.