Hands-On With Kura’s Breakthrough Wide Field Of View AR Technology

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San Francisco-based startup Kura Technologies (official website) claims it will launch compact AR glasses with a wide field of view, high resolution, high opacity, high brightness, and variable focus in mid-2020. We got the chance to try a series of four different prototypes from Kura that each demonstrated portions of these promises. We came away very impressed.

The nature of the demos we tried makes it hard to say what the actual finished device will be like, but we’re optimistic. None of the demos were shown on a product that resembles the mock-up images on their website and all four of our prototypes were described as being 8-12 months old from where they are at with the technology right now. You can read more about those demos deeper into this story.

Photographs and videos of any of the hardware at all were not allowed during my meeting — only workspace photos like the ones shown below.

We’re told Kura intends to bring a functional prototype to CES in January that will have all of the functionality in a single device. However, it’s worth noting that the device they plan to ship in mid-2020 is specifically targeting only enterprise customers first.

If they can pull it off — and that remains a big if — this startup will have created a product with specifications years ahead of all known public competitors, including Microsoft, Magic Leap, and Nreal.

The Kura Gallium

To understand more about why what they’re doing seems significant, let’s take a step back. Kura’s product is called Gallium. Kura describes Gallium as having “eyeglass form factor”, yet the claimed specifications are far beyond even any known large bulky AR headsets. 

According to marketing materials, the glasses are said to be powered by a hip-mounted compute pack via a Snapdragon 855, similar to how Magic Leap and Nreal work, but when speaking with CEO Kelly Peng, she told us the initial version will likely be tethered to a PC at first before providing the compute pack as a secondary power option later. Then further in the future, an adapter could allow for wireless communication with a PC that’s within range.

Kura’s website lists the price for the glasses with the compute pack as $1199, a Lite version without the compute pack for $899, or the compute pack on its own for $399.

Kura AR Glasses

Claimed Specifications

  • Field of View: 150° (Binocular, Diagonal)
  • Focus: 10 cm to infinity
  • Brightness: 4000 nits (outdoor viewable)
  • Max Transparency: 95%
  • Resolution: 8K 75Hz / 6K 100Hz / 4K144
  • Image Quality: 100% DCI-P3, HDR, True Black Capable
  • IPD: Automatic accommodation of 55-68mm
  • Weight: 80 grams

Kura AR Glasses

These specifications would put Gallium significantly ahead of any known AR headset. HoloLens 2 and Magic Leap have a maximum diagonal field of view of just about 50 degrees. Magic Leap One does not have sufficient brightness to be used outside, and even HoloLens 2 has just 1/4 the claimed brightness of Gallium.

Crucially, Magic Leap One supports just two focal planes, and HoloLens 2 is fixed focus. With automatic IPD accommodation and varifocal from 10cm to infinity, Gallium would be visually comfortable to wear all-day.

If the company truly is achieving all this in an 80g pair of glasses, it would likely accelerate the arrival of consumer AR by years. But the magnitude of these claims should be met with skepticism — even after we tried many of these features in person.

The Prototype Demos

During our visit to Kura we tried out four different prototype demos and spoke with CEO Kelly Peng for nearly an hour. Our tour of the Kura workplace, which doubles as a home for several of the core team members, was eye-opening (pun intended) to say the least.

Three of the four demos did not have head tracking and were not on wearable devices. Instead, they were mounted on tables, completely stationary, to show off the display, optics, field of view, brightness, etc. in controlled environments. This is common for early head-mounted technology prototypes.

The first demo, which was stationary on a mount, was a great example of their optics technology using 90%+ transparent lenses combined with high-brightness images to really make objects look like they were in the real environment rather than suffering from the faded and blurry effect you get in at lot of current AR devices. The models shown were far brighter than anything I’d seen in an AR device before with great focal clarity. As a glasses wearer, the quality of the image and the field of view was really encouraging to see in such an early stage of development.

The second demo was also stationary, but this one had an even larger field of view and showed a larger range of animations and types of content. Most of the animations shown in the demo video embedded above were shown during this demo, and they looked about as crisp as you could hope for in an AR device. Again, I was pretty impressed. This demo also included hand tracking so I could reach out and see my hand moving around. There wasn’t any interaction here but it did show a wide range of colors.

Next up, in demo number three, I tried a fully wearable device similar to the one pictured below as an early prototype that had head and hand tracking operational. Again, this was said to be at least eight months old. This was another good demonstration of the field of view because when my hand reached out into the view of the cameras and lenses, it added a augmented overlay to my skin and I could interact with all of the floating multi-colored particles. I could reach my right arm across my body and see the AR overlay from my fingertips all the way down to my elbow. It didn’t have a postage stamp-sized vision box like in other AR devices. There was a delay trail when I moved my arm for the overlay to re-align itself — but again, early prototypes and all that.

Finally the last demo was the roughest and most experimental of the bunch. One of the Kura Gallium’s touted features is the focal distance that can adapt from 10cm all the way to infinity. In this demo I saw a green matrix-style animation of a cat floating in front of my eyes, almost large enough to look life-sized, and then it slowly shrank and faded into the distance like it was being shot into space, Bag Raiders style. The trick here though is that I could still clearly see it even as it drifted into the distance. It never lost focus.

Kura Gallium Real Occipital

Kura appears to be using Occipital’s technology for positional tracking and scene reconstruction. This lets Kura focus their resources on the display technology. An Occipital video from November 2018 appears to show footage of an old Kura prototype. This prototype has a form factor significantly bulkier than the images shown today on Kura’s website and it’s very similar to one of the prototypes we tried — specifically the third one mentioned above.

Prior to our demo we reached out to Peng about this prototype, who confirmed on Twitter: “This is purely software or integration test demo we built early on, not the optics we are going for product. We used to make some giant reflectors optics 3-4 years ago, but since then totally moved away from that because of the size, contrast ratio, brightness issues.”

“Structured Geometric Waveguide”

How exactly is Kura achieving this?

Before this announcement, no credible company has claimed specifications anywhere near these. As recently as October 2018, Facebook’s chief AR and VR researcher Michael Abrash stated that the technology to enable compact wide FoV AR glasses “doesn’t yet exist“.

Almost all AR headsets today, including HoloLens 2 and Magic Leap One, use a diffractive waveguide. This technology has a fundamental limitation on field of view, and can make the real world appear dull due to the semitransparent nature of the see-through optics. This is all despite both products having a larger form factor and higher price than Gallium.

kura tech sensors pic

Kura claims their breakthrough is to use a microLED strip with a “structured geometric waveguide” as the combiner. While microLED displays are normally expensive and there are ongoing efforts to figure out how to affordably mass produce them, Kura’s design would only need a single row of pixels, which would allow for low cost and mass production.

The company describes this as follows:

“Like in a diffractive waveguide, light is coupled down the eyepiece via total internal reflection, but unlike a diffractive system, the structures in the eyepiece are explicitly much larger than a wavelength, which prevents colored ghosts in ambient light. Furthermore, the out-coupling elements are ordinary geometric optics, not holograms, which mitigates the narrow angle of acceptance from which diffractive elements suffer from. In addition, a careful multi-layer design allows the out-coupling elements to cover about 5% of the eyepiece’s area, allowing us to maintain very high transparency.”

It is possible Kura Technologies invented the missing display technology needed to make mass market AR glasses achievable. Again, though, it is hard to confirm exactly how the Gallium works without seeing all the pieces put together into a finalized product design. It is not uncommon for technologies to be possible and impressive in the prototype phase but never work out as a true product due to issues such as manufacturing being too hard or the expense involved in producing hardware at scale.

But since we’ve seen the pieces all functioning, albeit mostly separately at this stage, we’re optimistic enough to say Kura seems to be one of the key companies to keep an eye on in the AR space.

Kura Execs

Kura’s Team

Kura’s CEO Kelly Peng is on Forbes 30 under 30 for Manufacturing & Industry. At UC Berkeley, Peng says she worked on custom LiDAR designs for self driving vehicles. The CTO, Bayley Wang, was a high-performance optical simulation algorithms researcher at MIT and a math genius winner of a major North American undergraduate mathematics competition. The COO, Garrow Geer, is said to have been a particle accelerator operator and research engineer at Jefferson Lab and CERN.

Kura also tells us they have employed GoPro’s former lead electrical engineer, the designer of the electronics in the Xbox controller, “one of the most reputable optical experts in the world”, experts with over 100 patents in optics, displays and materials and several decades of combined experience in optical design, industry leaders with over 20 years of experience in AR/VR manufacturing and sales.

The company describes its team as “industry leaders, brilliant technologists and experienced subject-specific experts, with MIT, UC Berkeley, Stanford, EPFL & UBC alumni.”

Abrash Waveguides

Is Facebook Doing This Too?

Facebook, the company behind Oculus, is also developing AR glasses. While the company has not revealed any specifics on what display technology it is using, it did give several hints at Oculus Connect 5 in 2018.

When talking about display technologies, the company’s chief researcher Michael Abrash stated that waveguides “could potentially extend to any desired field of view in a slim form factor“. On screen, a graphic showed waveguides as allowing for up to 200 degree field of view.

He also noted that since no suitable display technology existed yet for AR, “we had no choice but to develop a new display system“.

At the time, this confused some optics experts, as well known limitations of diffractive waveguides limit their practical field of view to around 50 degrees. Abrash’s description of waveguides did not reflect any known designs.

Given Abrash’s comments, Facebook’s large investment in AR research, and the company’s hiring of renowned display technologies experts like Douglas Lanman, it is possible Abrash was referring to a similar system to what Kura is working on — a non-diffractive waveguide using geometric optics. 

We’ll keep a close eye on Oculus Connect 6 for any details on Facebook’s approach to AR optics and how it compares to what we’ve seen of Kura. 


Stay tuned to UploadVR for more details on Kura, including our in-depth interview with CEO Kelly Peng next week.


This article about Kura is co-authored by Staff Writer David Heaney, who did the background research and wrote the first draft, Senior Editor David Jagneaux, who provided the hands-on impressions and additional details, and Managing Editor Ian Hamilton, who provided editing.

Editor’s Note: We added clarification that Kura is targeting enterprise customers first.

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