Augmented reality (AR), virtual reality (VR) and hyper-realistic holograms are hurtling from the realm of science fiction into life. Just as wildly popular AR games like Pokemon Go and VR headsets have solidified the technology as a fun addition to daily life, so too could life-like talking holograms, such as those of Star Wars fame, conceivably replace video calls within our lifetimes.
However, experts say this development is held back by current hologram-projecting headset technologies. Most AR headsets project images using spatial light modulators (SLMs) which are limited by their relatively large pixel sizes resulting in low-resolution and small fields of view.
“This limitation is particularly crucial for applications such as 3D holographic displays where field of view is of fundamental importance to achieve good user experience,” explained Principal Investigator Arseniy Kuznetsov from A*STAR’s Institute of Materials Research and Engineering (IMRE).
To that end, Kuznetsov and his team explored a new strategy for enhancing SLM performance: shrinking their liquid crystal layers with Fabry-Perot nanocavities, optical resonators that help to reduce the pixel size.
The team has been working on small-pixel-size SLMs for years, and had previously reported breakthroughs for reducing their pixel size using metasurfaces. In this study, they focused on how a similar pixel size reduction can be achieved using Fabry-Perot nanocavities.
They found that besides being ultra-thin, Fabry-Perot nanocavities can also tune the properties of light at different wavelengths simultaneously to project full-colour holographic images. In addition, the researchers successfully reduced the pixel size of the SLM to around 1 µm, about four times smaller than current industry gold standard SLMs.
This method of introducing nanocavities to reduce the thickness of liquid crystal SLMs has since been patented by the group, an achievement that Kuznetsov believes has transformative potential in the industry.
“One of the most exciting future applications of SLM technologies is true 3D holographic displays, which will allow us to see true 3D images from a display instead of the 2D projections which we see now,” he said. “When developed, these kinds of devices will completely change the way we receive and interact with information.”
The team now has its sights set on bringing its innovation to the market. Scaling the technology up from a lab-made prototype to market-ready headsets can be complicated, but Kuznetsov remains optimistic. “This should be a solvable problem and we see a high potential for commercialising this technology in the future,” he concluded.
The A*STAR researchers contributing to this research are from the Institute of Materials Research and Engineering (IMRE).
