- Researchers from the University of Science and Technology of China have developed a new way to create dynamic ultrahigh-density 3D holographic projections.
- This new approach, called three-dimensional scattering-assisted dynamic holography (3D-SDH), overcomes two long-existing bottlenecks in current digital holographic techniques – low axial resolution and high interplane crosstalk – that limit the quality of the 3D display.
A team of researchers at the University of Science and Technology of China and the National University of Singapore have developed a new approach called three-dimensional scattering-assisted dynamic holography (3D-SDH) that enables dynamic ultrahigh-density 3D holographic projections.
This new technology could allow for more realistic representations of the world around us, opening up new possibilities for virtual reality and other applications.
According to Lei Gong, who led the research team, “a 3D hologram can present real 3D scenes with continuous and fine features,” and for virtual reality, this new method could be used with headset-based holographic displays to greatly improve the viewing angles and enhance the 3D viewing experience.
To create a realistic-looking holographic display of 3D objects, high-resolution images need to be projected onto a large number of successive planes that are spaced closely together to achieve high depth resolution.
The team’s new approach overcomes two long-existing bottlenecks in current digital holographic techniques, low axial resolution and high interplane crosstalk, which have prevented fine depth control of the hologram and limited the quality of the 3D display.
The researchers combined a spatial light modulator (SLM) with a diffuser to enable multiple image planes to be separated by a much smaller amount without being constrained by the properties of the SLM.
By also suppressing crosstalk between the planes and exploiting scattering of light and wavefront shaping, this setup enables ultrahigh-density 3D holographic projection.
The team’s new method achieved an improvement in axial resolution of more than three orders of magnitude over the conventional counterpart, which means a depth resolution more than three orders of magnitude greater than state-of-the-art methods for multiplane holographic projection.
The researchers demonstrated point-cloud 3D images and projected a 3D rocket model with 125 successive image planes at a depth interval of 0.96 mm in a single 1000×1000-pixel hologram. In comparison, another recently developed approach known as random vector-based computer-generated holography achieved 32 image planes with a depth interval of 3.75 mm.
While the 3D holograms demonstrated by the researchers are all point-cloud 3D images, ultimately, they would like to be able to project a collection of 3D objects with a hologram, which would require a higher pixel-count hologram and new algorithms.
The team believes their approach could also improve holography-based optical encryption by allowing more data to be encrypted in the hologram.