Design of a Bilayer Metalens for Red, Green, and Blue‐Achromatic Imaging with Wide Field of View

Metasurfaces offer precise manipulation of light through engineered subwavelength nanostructures. However, metalenses are challenging to design such that they simultaneously achieve wide field of view (WFOV), achromatic focusing at red (R), green (G), and blue (B), and high numerical aperture (NA). Here, an RGB‐achromatic bilayer metalens capable of wide‐angle imaging with a field of view of 80° and a NA of 0.65 is proposed. Utilizing silicon nitride bilayer meta‐atoms, the metalens maintains consistent focal lengths across RGB even at oblique incident angles up to 40°. Simulation results verify superior achromatic focusing and reduced coma aberration compared to conventional hyperbolic metalenses. This approach significantly enhances practical applicability of metalenses in digital imaging and display systems.