Single-shot isotropic differential interference contrast microscopy

Abstract

Differential interference contrast (DIC) microscopy allows high-contrast, low-phototoxicity, and label-free imaging of transparent biological objects, and has been applied in the field of cellular morphology, cell segmentation, particle tracking, optical measurement and others. Commercial DIC microscopy based on Nomarski or Wollaston prism resorts to the interference of two polarized waves with a lateral differential offset (shear) and axial phase shift (bias). However, the shear generated by these prisms is limited to the rectilinear direction, unfortunately resulting in anisotropic contrast imaging. Here we propose an ultracompact metasurface-assisted isotropic DIC (i-DIC) microscopy based on a grand original pattern of radial shear interferometry, that converts the rectilinear shear into rotationally symmetric along radial direction, enabling single-shot isotropic imaging capabilities. The i-DIC presents a complementary fusion of typical meta-optics, traditional microscopes and integrated optical system, and showcases the promising and synergetic advancements in edge detection, particle motion tracking, and label-free cellular imaging.

Trichannel Spin-Selective Metalenses

“…40 Furthermore, the two individual functionalities encoded into the cross-polarized channel here, deflection and OAM, could also be combined to provide complete control of the angle and SAM and OAM states of light (Supporting Note 10), while fractional 41 or higher orders of OAM could be investigated for other special image processing effects, such as using l = ±2 to highlight the curved contours by performing second order differentiation, 32 which has exciting potential for phase contrast imaging. 42,43 As an example of higher order topological charges, we experimentally demonstrate a metalens with l = ±3 in Supporting Note 11. Finally, large-scale fabrication processes could be employed to create metalenses that are large enough for commercial applications, 44,45 as well as integrating liquid crystals as a method of actively switching between the three different functionalities.…”

“…Furthermore, chirality could be utilized to provide additional and distinctive functionalities to the cross-polarized components through the design of a chiral meta-atom . Furthermore, the two individual functionalities encoded into the cross-polarized channel here, deflection and OAM, could also be combined to provide complete control of the angle and SAM and OAM states of light (Supporting Note 10), while fractional or higher orders of OAM could be investigated for other special image processing effects, such as using l = ±2 to highlight the curved contours by performing second order differentiation, which has exciting potential for phase contrast imaging. , As an example of higher order topological charges, we experimentally demonstrate a metalens with l = ±3 in Supporting Note 11. Finally, large-scale fabrication processes could be employed to create metalenses that are large enough for commercial applications, , as well as integrating liquid crystals as a method of actively switching between the three different functionalities. , We envision that our spin-selective metalenses could be implemented as actively modulated flat optical devices that achieve not only bright-field imaging but also chiral bioimaging and all-optical image processing, all within the same miniaturized footprint.…”

Polychromatic Dual-Mode Imaging with Structured Chiral Photonic Crystals

“…In addition to digital image processing methods, the diffraction of light actually offers a natural platform for implementing various kinds of analog computations, like Fourier transform and convolution. The desired optical edge detection can be achieved by appropriate wavefront-shaping components like metasurfaces − and spatial light modulators. , Phase contrast imaging − and differential interference contrast imaging are two typical methods. They have been successfully used to highlight the edges and reveal the geometric shapes of undyed cells.…”

Intelligent Phase Contrast Meta-Microscope System

“…Metalenses, a subset of metasurfaces specifically designed for focusing, have already been intensively utilized in a variety of biomedical imaging fields, such as endomicroscopy, light sheet fluorescence microscopy, etc., − allowing device designs more compact than those of their conventional counterparts. Recently, computing metasurfaces have been proposed, offering optically mathematical operations like spatial first-order and second-order differentiation and filtering, which are essential for image processing and analysis. − However, most of the previous works substitute only a few optical elements with metasurfaces, resulting in the conventional optical components still dominating the performance of the system. For example, while the spiral metalens based on the geometric method design proposed by Kim et al shows promising results in isotropic edge-enhanced imaging, it still relies on the support of conventional circular polarizers, an objective, and a tube lens …”