High Space‐Bandwidth‐Product (SBP) Hologram Carriers Toward Photorealistic 3D Holography

Abstract 3D holography capable of reproducing all necessary visual cues is considered the most promising route to present photorealistic 3D images. Three elements involving computer‐generated hologram (CGH) algorithms, hologram carriers, and optical systems are prerequisites to create high‐quality holographic displays for photorealistic 3D holography. Especially, the hologram carrier directly determines the holographic display capability and the design of high space‐bandwidth‐product (SBP) optical systems. Currently, two categories of hologram carriers, i.e., spatial light modulators (SLM) and metasurfaces, are regarded as promising candidates for photorealistic 3D holography. However, most of their SBP capability still cannot match the amount of information generated by the CGH. To address this issue, tremendous efforts are made to improve the capability of hologram carriers. Here, the main hologram carriers (from SLM to metasurfaces) that are widely utilized in holography systems to achieve high SBP capability (high resolution, wide viewing angles, and large sizes) are reviewed. The purpose of this review is to identify the key challenges and future directions of SLM‐based and metasurface‐based holography for photorealistic 3D holographic images.