Three-dimensional light field display technology marks a major leap forward in display technology and is of great significance. As technology advances, traditional 2D displays have reached their limits in conveying visual information and fall short of providing the depth and spatial perception that people desire. As a result, three-dimensional light field display technology has emerged to simulate the distribution of light rays in real 3D scenes, delivering a seamless and lifelike stereoscopic visual experience. Three-dimensional light field display technology can reproduce perspectives and details similar to those in the real world, which overcomes the limitations of 2D displays that cannot convey depth information and greatly enhances user immersion. This technology not only improves the realism of images but also enables free-viewpoint stereoscopic displays, allowing users to experience a more intuitive and immersive environment. Additionally, it has broad application potential in fields such as medicine, education, and industrial design. For example, it can assist doctors with more precise preoperative planning and intraoperative navigation, and help engineers with virtual prototype testing during design and modeling processes, thus enhancing work efficiency and outcomes. Despite facing challenges such as high cost and technical complexity, three-dimensional light field display technology is expected to achieve greater precision and broader applications in the future with ongoing advancements. This will push display technology to new dimensions and offer users a more realistic and immersive visual experience.

There are many forms of high-quality three-dimensional light field displays, including those based on cylindrical lens arrays, microlens arrays, diffraction gratings, and optical waveguide elements. In 2018, Liu et al. at Zhejiang University proposed a large-scale, multi-projector 360° light field 3D display system, using 360 projectors to achieve a display area of 1.8 m×2.78 m with a rendering rate of 30 frame/s or higher. In the same year, Wang’s team at the Beijing Institute of Technology introduced an optical scheme employing discrete lens arrays to create an optical perspective near-eye light field display, as shown in Fig. 11(a). Experimental results indicate that this method can achieve corrected depth perception of virtual information in augmented reality applications. In 2019, Liu et al. from the Beijing University of Posts and Telecommunications demonstrated a time-multiplexed light field display with a 120° wide viewing angle, using three sets of directional backlighting and fast-switching liquid crystal display panels. This system achieved a 120° viewing angle, 192 viewpoints, and a 30 cm display depth. In 2021, Xing et al. from Sichuan University presented a desktop integrated imaging 3D display system based on ring-shaped point light sources. This system can display 3D images to multiple viewers from an inclined angle within a standard ring-shaped viewing area. In the same year, Liu et al. from Beijing University of Posts and Telecommunications proposed an optical scheme based on directional diffusion films and trapezoidal composite grating lens units. This technology strengthens viewpoint utilization while expanding the viewing angle, presenting natural 3D images with accurate depth perception and occlusion relationships within a 65° viewing range and 30 cm display depth. In 2024, Yu et al. from Beijing University of Posts and Telecommunications introduced the concept of beam divergence angle to analyze the display depth of three-dimensional light field display systems. In the same year, Deng et al. from Sichuan University proposed a dual-mode optical perspective integrated imaging display system that can simultaneously reconstruct 3D images in both real and virtual display modes, which greatly extends the depth of field for 3D images, as shown in Fig. 15(a).

As carriers of visual information, display devices play an indispensable role in our daily lives. As the most promising new generation of naked-eye 3D display technology, 3D light field display technology has become an ideal choice due to its features, such as accurate depth cues, the ability to allow multiple people to view simultaneously, and high-quality display effects. Therefore, achieving high-fidelity 3D light field display is a key challenge for making significant progress in the market. In summary, the key technologies of high-fidelity 3D light field display need to be explored in greater detail to promote the application and development of light field display technology.