Augmented reality display device with continuous depth rendering capabilities

Abstract True 3D display with continuous depth rendering is a key issue for augmented reality display system. However, the discrete sampling characteristics of current display devices makes the 3D images discontinuous in both lateral and depth directions. For depth information, very limited depth planes can be rendered, especially when the resolution of the display device is low. To address the limitation, a kind of augmented reality display device that can output continuous depth information using a modulated illumination integral imaging technique is demonstrated. Light field with a continuous directional component is achieved in a digitized integral imaging system by using a modulated convergent backlight. A custom-designed transparent off-axis spherical reflective lens is used as an optical combiner to project the light field images into the real world. Two prototype augmented reality display devices are fabricated that provided continuous depth information ranging from 0.5 m to 3 m for 3D images in front of the optical combiner. 3D images with continuous focus cues and double depth of field are realized using a simple optical structure. The imaging mechanisms of the augmented reality display devices are deduced analytically. The imaging characters of the augmented reality display devices are tested and verified.