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With the development of the information industry, the wearable three‐dimensional (3D) near‐eye display that can provide complete visual information has attracted increasing attention. Compared with other existing 3D display technologies, the holographic display is a promising true 3D display technology that can fully record and reproduce the original 3D scenes. The ability to present a continuous parallax and depth perception gives holography technology an unprecedented promise in the next‐generation 3D near‐eye display. However, currently available holographic near‐eye display systems can only provide a limited viewing area (including the field of view and eyebox), greatly restricting its practical application. Focusing on the development requirements of large viewing‐area 3D holographic near‐eye display, the reasons are introduced first why the viewing area of current holographic displays is limited and then the existing solutions from different aspects, including multiplexing‐based methods, steering viewing window methods, aperiodic wavefront modulation methods, and some emerging holographic display technologies are summarized. These various solutions are analyzed respectively, and their representative works are investigated. In addition, the different applications of holography in the near‐eye display system are also discussed. Finally, the advantages and disadvantages of these techniques are compared and perspectives are given. [ABSTRACT FROM AUTHOR]

• A new perspective light field-based holographic algorithm that can generate high-quality 3D holograms for arbitrary scenes. • The constructed radiance field representation can avoid the spatial-angular tradeoff and achieve high-resolution reconstruction within a deep depth range. • The computational hologram provides the natural occlusion and view-dependent effects. Conventional light field-based computer-generated holograms, such as holographic stereograms, can provide nature parallax and accurate occlusion relation but are restricted by the inherent tradeoff concerning the angular and spatial resolution of the reconstructed optical field. In contrast, Wigner distribution function based light field generated holograms, also called non-hogel-based holograms, release this limitation by using basic ray-to-wave transformation frameworks. However, at present, this transformation framework is accurate only for generating holograms from orthogonal light field images of 3D scenes with a limited depth range and size. Thus, the radiance field holography method is proposed in this paper to generate high-quality 3D holograms for arbitrary scenes that can achieve high-resolution reconstruction within a deep depth range. In our method, a proposed radiance field is constructed from the perspective light field, which consists of multiple reference planes to resample and redistribute the light rays to represent the diffracted optical field of the 3D objects according to our developed sampling criterion. The complex optical field of the 3D object can be synthesized from these reference planes based on inverse Wigner transform and Fresnel propagation. As a result, both the numerical simulations and the optical experiments are implemented, and it is demonstrated that the high-quality 3D reconstruction of the synthesized hologram is achieved, which reflects the highest reconstruction resolution among the existing methods, the large depth range with accurate refocus and defocus, and the natural view-dependent effects. [ABSTRACT FROM AUTHOR]

Manipulation of light energy flow within the tight focus not only is important to the fundamental study of light-matter interactions but also underpins significant practical applications. However, the coupling between the electric and the magnetic fields of a focused light beam sets a fundamental barrier for independent control of these field components, restricting the focal energy flow primarily in the axial direction. In this paper, a 4π microscopic configuration is theoretically proposed to untangle the tight relation between the electric field and the magnetic field in a subwavelength-scale focal voxel. By independently altering the amplitudes of different field components in the focal region, energy flow with three-dimensionally unlimited orientation and ultra-high orientation purity (more than 90%) can be generated. This result expands the flexibility of energy flow manipulations and holds great potential in nanophotonics such as light scattering and optical force at subwavelength dimensions.