Meta-lens transformation of a vector vortex beam into a highly directive radiation with arbitrary linear polarization

We present a cascaded meta-lens composed of a polarization-selective surface followed by a phase-modulation surface to transform an incident vector vortex beam into a highly directive beam with enhanced polarization purity. More specifically, the first layer performs polarization filtering to extract the desired linear component, upon which the second layer imposes a tailored phase profile derived from the near-field phase of the original vector vortex beams to compensate residual wavefront distortions. Especially, by simply rotating the meta-lens, the overall system enables flexible synthesis of arbitrary linear polarizations, thereby linking the spatially varying polarization states of vector vortex beams with the polarization agility required for directive radiation. This cascaded strategy offers a practical route for efficient conversion of vector vortex beams into linearly polarized beams, demonstrating strong potential for advanced beam-forming and polarization-control applications.