Achromatic Petal-Shaped Beam Generation and Information Encoding Based on Perfect Vortex Beam

Based on the successful generation of petal-shaped beams with controllable topological charges (TCs), sizes, and rotation angles, this work employs a spatially multiplexed all-dielectric TiO₂ transmissive array to achieve focused petal-shaped beams at 480 nm, 530 nm, and 630 nm wavelengths, converging to the same focal plane through numerical simulation. We propose a new encoding scheme with different rotation angles and spot numbers, based on the characteristic doughnut-shaped intensity profile with certain TCs and an incremental rotational modulation, thereby enhancing the capacity of information transmission. Leveraging the high spatial multiplexing capability of all-dielectric metasurfaces and the flexible tunability of petal-shaped beams, we present the design and implementation of an achromatic petal-shaped beam platform operating across multiple wavelength bands. These results lay the groundwork for expanding the applications of petal-shaped beams in information processing and optical micromanipulation.