Augmented Reality Vector Light Field Display with Large Viewing Distance Based on Pixelated Multilevel Blazed Gratings

Jiacheng Shi,Wen Qiao,Min Yang,Jianyu Hua,Fengbin Zhou

doi:10.3390/photonics8080337

Abstract

Glasses-free augmented reality (AR) 3D display has attracted great interest in its ability to merge virtual 3D objects with real scenes naturally, without the aid of any wearable devices. Here we propose an AR vector light field display based on a view combiner and an off-the-shelf purchased projector. The view combiner is sparsely covered with pixelated multilevel blazed gratings (MBG) for the projection of perspective virtual images. Multi-order diffraction of the MBG is designed to increase the viewing distance and vertical viewing angle. In a 20-inch prototype, multiple sets of 16 horizontal views form a smooth parallax. The viewing distance of the 3D scene is larger than 5 m. The vertical viewing angle is 15.6°. The light efficiencies of all views are larger than 53%. We demonstrate that the displayed virtual 3D scene retains natural motion parallax and high brightness while having a consistent occlusion effect with natural objects. This research can be extended to applications in areas such as human–computer interaction, entertainment, education, and medical care.

Highlights

With the aid of optics and computer science, augmented reality (AR) enriches the physical world by overlaying virtual contents and information and offers unprecedented visual experiences for people [1].To take the advancement in glasses-free 3D display [2,3,4,5,6,7,8], people combine AR technology with glasses-free 3D display to avoid any wearable devices
Glasses-free AR 3D display can be divided into reflection-type AR display [11,12] and optical see-through (OST) display [13,14,15,16,17,18,19,20,21,22]
A compact reflection-type AR 3D display with a size of 152 × 76 mm was proposed based on a reflective polarizer (RP), a conventional lens array, and a 2D display [12]

Summary

Introduction

With the aid of optics and computer science, augmented reality (AR) enriches the physical world by overlaying virtual contents and information and offers unprecedented visual experiences for people [1].To take the advancement in glasses-free 3D display [2,3,4,5,6,7,8], people combine AR technology with glasses-free 3D display to avoid any wearable devices. The viewing angle was 20.8◦, and the diffraction efficiency of Photonics 2021, 8, 337 The OST glasses-free 3D display is another type of glasses-free AR 3D display that allows people to directly perceive the real physical world through a transparent combiner.

Results

Conclusion