Directionally Asymmetric Holographic Imaging for Arbitrary Polarization States Using Janus Metasurfaces

Janus metasurfaces have emerged as a powerful platform for directionally asymmetric holographic imaging. However, existing designs often suffer from limitations such as complex fabrication processes, reliance on spatial multiplexing or vertical stacking, restricted polarization control, or significant Ohmic losses—particularly preventing operation in the visible spectrum. In this study, single‐layer dielectric Janus metasurface holograms are presented utilizing TiO 2 meta‐atoms, each capable of operating simultaneously for forward and backward illumination, to overcome these obstacles. By incorporating the Dammann grating principle and precise phase manipulation, this design generates high‐fidelity holographic images for arbitrary polarized light at wavelength of 532 nm. This approach not only achieves simplified fabrication and minimizes losses but also broadens the applicability of holography, paving the way for diverse innovations in compact and versatile optical technologies.