Compact imaging system based on multi-variable focal lens system in AR display

Abstract

Augmented Reality (AR) has been attracted considerable attention according to the demand for non-face-to-face services. The principle of AR is overlapping a virtual image in the real world. To display a virtual image at a proper position, depth of field is a significant factor. In this paper, we propose a multi-variable focal lens system that can dynamically tune a depth of field. By using a multifocal lens that has several different focal lengths, an image has depth information corresponding to each focal length. A focus tunable lens controls a focused area and magnification to display the appropriate position and size. The proposed system has a huge advantage in form factor and fever issues owing to its simple architecture. In order to verify the feasibility of the system for AR, numerical simulations are performed. The system divides a 2D image into focused and defocused areas. Focused and defocused areas show feasibility that can be tuned by the multifocal lens and focus tunable lens. The results show the depth range from 0.3 m to 2 m (3.3D to 0.5D), which is determined by the design of the system.