Large-pixel-count hologram data processing for holographic 3D display

摘要

The pixel count of hologram for a holographic 3D display system increases rapidly with the increase in reconstructed object size and viewing angle. According to our analysis, for 10 inch reconstructed object size with 5° viewing angle, a hologram with a pixel count of 378 Million is required. Such a large pixel count is a challenge for both hologram computation and hologram data transmission. The computation load is analyzed to be a few hundreds of T flop for the object with a few million object points, and the hologram data transmission rate required is analyzed to be 22.3 Gbps and 67.0 Gbps for monochrome display and color display using time division multiplexing at 60 Hz, respectively. A computer cluster with 32.7 Tflops GPU computing ability and 60 Gbps transmission bandwidth was built to meet the hardware requirements for large-pixel-count hologram computation and transmission. A distributed computation method was implemented for computing large-pixel-count holograms. Computation time of 5.6 seconds was achieved for 378-Mpixel hologram containing information of 1.7 M object points. During the playback of holographic video using our holographic 3D display system, the hologram data was read out from SSDs, transmitted over the high speed network, and finally launched onto SLMs for reconstruction. A data transmission rate of 31.8 Gbps was achieved, which corresponded to 378-Mpixel hologram at 84 Hz for monochrome reconstruction and full color reconstruction using space division multiplexing. The increasing demand for computation power and data transmission rate of large-pixel-count hologram video displays has been effectively addressed.