Large-scale metagrating complex-based light field 3D display with space-variant resolution for non-uniform distribution of information and energy

Glasses-free three-dimensional (3D) display has attracted wide interest for providing stereoscopic virtual contents with depth cues. However, how to achieve high spatial and angular resolution while keeping ultrawide field of view (FOV) remains a significant challenge in 3D display. Here, we propose a light field 3D display with space-variant resolution for non-uniform distribution of information and energy. The spatial resolution of each view is modulated according to watching habit. A large-scale combination of pixelated 1D and 2D metagratings is used to manipulate dot and horizontal line views. With the joint modulation of pixel density and view arrangement, the information density and illuminance of high-demand views are at most 5.6 times and 16 times that of low-demand views, respectively. Furthermore, a full-color and video rate light field 3D display with non-uniform information distribution is demonstrated. The prototype provides 3D images with a high spatial resolution of 119.6 pixels per inch and a high angular resolution of 0.25 views per degree in the high-demand views. An ultrawide viewing angle of 140° is also provided. The proposed light field 3D display does not require ultrahigh-resolution display panels and has form factors of thin and light. Thus, it has the potential to be used in portable electronics, window display, exhibition display, as well as tabletop display.