A team of researchers from NVIDIA Research and Stanford University published a recent paper demonstrating a pair of thin holographic VR glasses. The scientists also proposed new algorithms for rendering the image for improved visual quality. It’s part of an ongoing effort to make VR headsets that are comfortable to use for long periods. “Holographic display is the only viable solution so far that provides 3D images in a glasses-form factor,” Jonghyun Kim, an NVIDIA researcher and one of the paper’s authors, told Lifewire in an email interview. “Since the users want something lightweight, cool, and very immersive, I think the industry will eventually adopt holographic displays as a standard.”
Your World in 3D
Nvidia’s proposed holographic glasses boast a 2.5mm thickness for the entire display. If the research translates into a genuine product, the glass would be much less bulky than the several inches of plastic that jut out from your face while wearing the popular Meta Quest 2 headset. “Since holograms can be located almost anywhere, there is no need for the gap between the display panel and eyepiece, which means we can shrink down the thickness without any gap between optical components,” Kim said. The researchers say that their proposed design shows holograms through the use of a spatial light modulator. But the headset would also be able to display flat images as well. “Holograms in displays basically means natural 3D images,” Kim said. “By modulating phase of the light instead of amplitude, the system can provide focus cues in front of or behind the display panel plane. Compared to the current VR headset, which provides binocular disparity only, holograms naturally provide additional accommodation cues because of their unique light wave reconstruction mechanism.” The proposed glasses would be a first of their kind for personal holographic displays Even state-of-the-art commercial VR displays don’t use any hologram or holographic optical elements yet, Kim said. Holographic displays are expensive and difficult to manufacture and require advanced computers to run. Developing the holographic headset was a major challenge, Kim said, due to the complexities of calibrating the display and figuring out how to apply enough computing power to process the images. “Since holographic displays require wavelength-level alignment and calibration, we need to capture a lot of images and train a network for each system,” Kim said. “With this camera-in-the-loop training, we can calibrate the system and generate a compensated phase pattern. So the computational load of phase pattern generation is much higher than normal stereoscopic VR displays.”
The Future May Be Holographic
NVIDIA isn’t the only company working on holographic displays for VR. Meta last year published research into holographic lenses in which they claimed to have created a VR display and lens that together are 9mm thick. “We anticipate that such lightweight and comfortable form factors may enable extended VR sessions and new use cases, including productivity,” the researchers wrote in a blog post. “The work demonstrates the promise of better visual performance, as well: Laser illumination is used to deliver a much wider gamut of colors to VR displays, and progress is made toward scaling resolution to the limit of human vision.” D.J. Smith, the chief creative officer of the VR company The Glimpse Group, told Lifewire in an email that holographic VR could be the driving force behind new kinds of entertainment. “Examples of live entertainment in VR will include everything from concerts to comedy clubs where performers are live broadcast directly into VR scenes,” he said. But before holographic VR heads to the shelves of your local retailer, there are significant challenges to making them a reality, Smith said. One of the main difficulties is placing the holographic content into the 3D environment in a way that makes it appear that the hologram is naturally in the VR scene. “For example, often the holographic content is imported into the scene as a two-dimensional “billboard” panel,” Smith said. “If a user walks around the hologram, the user’s point of view can break the holographic illusion. It is very important to design the scene so that a user can not go to specific areas of the environment that break the holographic illusion.”
