Imagine the big game is on, and you’re watching your favorite team trounce its rival on a 122-inch screen that displays every detail. But the curved display is actually only a 32-inch model that, when you place your face near it, generates the illusion of a much more massive display. A new light-field display now seeks to create such an immersive panoramic virtual screen without goggles.
Immersive displays generally either involve giant screens à la IMAX, virtual reality (VR), or augmented reality (AR) headsets that place tiny screens and lenses close to a person’s eyes to simulate large screens that encompass most of a user’s field of view. Engaging as immersive displays are, electrical engineer Barmak Heshmat and his colleagues at an AR startup, “realized the bitter reality that people don’t want to wear headgear; it’s just too much friction to have something on your face. I think people can talk volumes about that, considering that now everyone has to wear masks.
“Just imagine wearing a 200-gram object on your face for 6.5 hours,” Heshmat says. “It is really exhausting, but 6.5 hours is the average time we spend in front of computers, easily, every day.”
This led Heshmat to find a solution “that gives you some level of immersion of a headset but also provides the comfort and image accuracy of a monitor,” he says. He co-founded the display technology company Brelyon in San Mateo, Calif.; the startup came out of stealth mode with a TEDx talk on 22 June. (“Brelyon” is the Persian name for the ‘brilliant’ cut of diamond.)
The 13-by-30-inch pilot displays Brelyon is developing will have a perceived screen 122 inches large, as seen from 55 inches away, says Heshmat, who is Brelyon’s CEO. The displays will each provide an immersive 101-degree field of view, with a 4K to 8K resolution and high frame rate, he adds.
“We can replace six 32-inch monitors with the size of one,” Heshmat says.
The company says that, whereas conventional displays direct flat images at viewers, its light-field display creates a window-like 3-D scene by recreating the field of light rays that might travel from every point and in every direction within a 3-D space.
Previous research explored many different approaches toward light-field displays. For example, so-called autostereoscopic displays use pixels that send light in specific directions to project a different image at each of a viewer’s eyes, whereas multifocal displays use focus-tunable lenses to generate multiple 2-D images that span a range of depths on which eyes can focus.
Scientists are generally developing autostereoscopic and multifocal displays for 3-D applications, Heshmat says. In contrast, Brelyon aims to present virtual panoramic 2-D images to the viewer. Instead of generating images appearing to be set at a range of distances from the eye, Brelyon’s light-field display is “sparse-depth,” focused on producing the illusion of a large immersive image.
“We call it a near-head display,” Heshmat says. The screen is designed for viewing from a distance of about 2 to 20 inches.
Brelyon’s display is curved both vertically and horizontally. This causes the layers of light it emits to overlap in the space in front of the display where users place their heads. “In some cases, there are two layers or more on top of each other like onion layers at different depths,” Heshmat says. As such, Heshmat calls Brelyon’s device a concentric light-field display.
The curvature of the display increases the angles at which it can project light at viewer. This in turn increases the field of view it provides, “which is what you need to create the illusion of a larger screen,” Heshmat says.
To ensure that the immersive image appears to be a comfortable distance from the user, Brelyon places an optical component on top of a conventional LCD or OLED screen that manipulates the light emitted from the display. This device makes each pixel appear further away than its actual physical distance from the user, Heshmat says.
Specifically, the optical component manipulates the wavefront of light emitted by the display. The light from a point source like a pixel on a computer screen creates almost a spherical wavefront, and the human eye accounts for the curvature of this wavefront when it creates an image. “Our technology allows you to change this wavefront curvature without the need to physically put the light source further back,” Heshmat says.
Major companies such as Samsung and LG previously offered curved screen televisions. However, Brelyon’s invention differs from those displays in a number of key ways: Viewers are meant to sit up close to Brelyon’s display as opposed to far away, and the light field from Brelyon’s display emulates a much larger image than seen with previous curved displays.
A key advantage of Brelyon’s screen over conventional monitors is that it takes up much less space than multiple monitors while also providing an immersive experience, the company says. An advantage it has over VR and AR is that it has better image quality and doesn’;t require cumbersome headgear.
“Brelyon is really the first company that is telling the AR and VR community, ‘Hey guys, wait a minute: Who said that immersion always equals headset?’” Heshmat says. “There is plenty of room between a near-eye display and a freestanding flat monitor. We are exploring that uncharted territory.”
Brelyon is starting with a business-to-business (B2B) model, aiming its displays at finance centers, teleoperation centers and gaming centers. “This helps us to test our technology in the field,” Heshmat says. Assuming Brelyon succeeds in its endeavors, it will then focus on the general consumer market, he adds.
Future research will focus on improving the efficiency and fidelity of light-field experiences from the display, as well as integrating this type of display with other devices, Heshmat says.
Charles Q. Choi is a science reporter who contributes regularly to IEEE Spectrum. He has written for Scientific American, The New York Times, Wired, and Science, among others.