Color Holographic Display Based on Complex-Amplitude Metasurface

Holography is an ideal solution for truly 3D display. Complex-amplitude hologram can realize high quality reconstructions compared to amplitude-only hologram and phase-only hologram. It is difficult for conventional spatial light modulators to achieve complex-amplitude holographic display while ensuring temporal and spatial resolution, let alone color complex-amplitude holographic display. Benefiting from the subwavelength pixel size and the powerful multi-dimensional electromagnetic wave control capabilities, a few metasurface hologram with large viewing angle, high resolution, and no high-order diffraction crosstalk based on complex-amplitude control have been studied and realized. Nevertheless, colorful complex-amplitude metasurface holography at visible frequency has not been implemented yet. Here a complex-amplitude dual-wavelength metasurface holography is proposed by using a single cross-shaped meta-atom. The polarization conversion efficiency of each wavelength channel is controlled by adjusting the geometric size, while the phase value from 0 to 2π is manipulated based on the Pancharatnam–Berry(PB) phase by rotating the meta-atom. Without spatial multiplexing, the high-resolution property of the metasurface is retained. The designed metasurface achieves dual-color holographic display in the far-field and the experimental results agree well with the simulation results. The proposed metasurface opens a pathway for high quality color holographic displays and other applications that require complex-amplitude modulation at different wavelengths.