Hologram image quality of binary modulating SLM-based holographic display (Conference Presentation)

We have successfully implemented and reported 360-degree viewable tabletop-style holographic display prototype systems. In order to support 360 degree horizontal viewing angle, which is very much wider than previous systems, we used binary amplitude modulating DMD device as SLM of the display system. DMD has higher total data rate due to its high refresh rate, which is denoted as extended SBP or eSBP, than other SLM devices like LCD or LCoS. This is much beneficial for the system design aiming at wider viewing angle or larger image size. However, Binary amplitude modulating hologram has inherent limitation in terms of resulting hologram image quality, and thus there has been lots of studies on quality-improving coding algorithms like BERD or DBS. In this paper, pros and cons of using DMD in holographic display system are discussed, and in-depth analysis and experimental results are presented on the behavior and limitations of the reconstructed image quality based on our prototype system. Image quality is measured with various metrics like 3D-MTF, depth resolution and color reproducing fidelity for different pixel resolutions from QVGA up to 4K UHD. 3D-MTF represents lateral image resolution and depth resolution has to do with degree of supporting accommodation of human vision in holographic displays. Based on these observations, we draw some projection on the required pixel resolutions of binary modulating SLM device for achieving acceptable hologram image quality.