Voxel characteristic estimation of integral imaging display system using self-interference incoherent digital holography.

Three-dimensional (3D) images reconstructed by integral imaging display are captured as a complex hologram using self-interference incoherent digital holography (SIDH) and analyzed for the volumetric image characteristics. The integrated images can present 3D perception through not only binocular disparity but also volumetric property, which is represented in forming a volume picture element, called 'voxel', and an important criterion to distinguish the integral imaging from the multiview 3D display. Since SIDH can record the complex hologram under incoherent lighting conditions, the SIDH camera system has the advantage to measure the voxel formed with the incoherent light fields. In this paper, we propose a technique to estimate and analyze the voxel characteristics of the integral imaging system such as the depth location and resolution. The captured holograms of the integrated images are numerically reconstructed by depth for the voxel analysis. The depth location of the integrated image can be calculated and obtained using the autofocus algorithms and the focus metrics values, which also show the modalities of depth resolution. The estimation method of this paper can be applied to the accurate and quantitative analysis of the volumetric characteristics of light field 3D displays.

Design of ghost-free floating 3D display with narrow thickness using offset lens and dihedral corner reflector arrays.

A floating 3D display with a dihedral corner reflector array (DCRA) is presented to improve space efficiency and eliminate ghost images. Floating displays using a DCRA have the space efficiency problem of having a system thickness equal to the height of the floating image and the problem of a ghost image interrupting the visibility of the floating display. The DCRA is analyzed to find the ghost image region. Based on the analysis, an off-axis integral floating display is placed outside the ghost image region to avoid the ghost image. To increase space efficiency, the optical path is folded using a mirror. In addition, the off-axis integral floating display is used to create a tilt angle for projecting the input image onto the DCRA in a proposed confined and narrow system to observe the complete 3D image. The effectiveness of the system was verified through simulations and experiments.