Color Holographic Display Based on Complex‐Amplitude Metasurface

Abstract

AbstractHolography 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.