Virtual Reality (VR), Augmented Reality (AR), Mixed Reality (MR), Extended Reality (XR): Success for the technologies behind these oft-heard terms could be right around the corner. They could be ready to confirm the dream of AR for everyone, supplanting smartphones as the next big consumer revolution. Companies have invested lots of money to develop the required technology-enabling building blocks in-house.
Among such building blocks, the optical elements represent one of the most challenging ones for AR headsets. Yole Développement (Yole) has addressed this topic in its technology and market analysis report, “Displays and optical vision systems for VR, AR & MR” released a few months ago, discussing the challenges and trends for headsets. Specifically, the report illustrates a path toward consumer acceptance of AR headsets. Apart from the price point, a sleek form factor is of utmost importance. And to be able to provide a sleek form factor, it seems that waveguiding lenses are one of the most obvious choices. Among all the companies working on these lenses, two main technologies compete: surface relief gratings versus holographic components.
One of the major companies in this industry is DigiLens Inc. which has adopted the holographic route for its AR lenses. Dr. Zine Bouhamri, Display Technology and Market Analyst for Yole, has had the chance to interview Dr. Jonathan Waldern, Founder, Chairman and CTO of DigiLens Inc., to discuss the future of the company and of the industry as a whole.
Zine Bouhamri (ZB): Could you please introduce DigiLens and its activities?
Jonathan Waldern (JW): The company was founded by Jonathan Waldern in 2003 under the name SBG Labs, after our Switchable Bragg Grating technology, and renamed DigiLens in 2015.
DigiLens’s mission is to become a leader in the development of next generation waveguide-based AR displays. We believe our proprietary nanomaterials, holographic manufacturing processes and display reference designs are unique in the waveguide display industry.
The company licenses optical nanomaterials and holographic printing tools to leading manufacturers of waveguide optics to help accelerate delivery of their AR products in the automotive, military, aerospace and consumer electronics fields.
DigiLens AR waveguides are already entering the market starting with the world’s first commercial waveguide HUD for aerospace, called AeroHUD, which was launched in 2016. The MonoHUD monocular HUD for motorcycle helmet is due to enter production at the end of 2018.
ZB: Could you describe your technology?
JW: Our speciality is holographic waveguides, currently one of the principal contenders in the waveguide display arena. The other key competing technologies are Surface Relief Gratngs (SRGs), being developed by Microsoft, Vuzix, Magic Leap and Wave Optics and Cascaded Mirrors, developed by Lumus. Instead of forming complex surface relief structures, Like Microsoft, or embedding multi-coating reflectors in waveguides, like Lumus, we use Bragg gratings printed into a monomer liquid crystal mixture to form thin, highly transparent gratings, abolishing expensive etching and nano lithographic processing steps.
We take holographic waveguides to new levels by adding switching and high index modulation. After early explorations of reflection holograms, DigiLens made the decision to specialise in thin transmission Bragg gratings, which when implemented in waveguides, offer more versatility than reflection Bragg gratings in terms of enabling the range of beam management capabilities needed for AR.
We like to describe our approach as performing optical origami. Using a comprehensive toolkit of basic grating setups, we can design any waveguide architecture needed for an AR display as well as eye trackers and other sensors that are needed to fully realize AR. Uniquely, our technology allows all these functions to be addressed with a common design methodology, material, and process, reducing them to additional layers in a stack.
One design challenge was that current design tools cannot model complex waveguide gratings to the degree required for our waveguide let alone deal with the birefringent properties of LC polymer gratings. To rectify this problem, we have developed our own custom ray-tracing tools that operate within ZEMAX. Eventually, these design tools will be made available to our licensees to allow them to author custom waveguide implementations based on our patented reference designs.
DigiLens EyeHUD: 93% clear, 6000 nits daylight-bright – for all-day-wearable “Enterprise” applications
(Source: courtesy of DigiLens)
ZB: What are the advantages of your holographic optical elements compared to other technologies?
JW: We provide wide FOV color now, with FOV with designs and processes scalable any AR FOV and form factor, from near-eye to retail displays.
Other USPs are high transparency, high efficiency, capability of getting down to a single RGB layer (SRG waveguide are unlikely to get below two waveguides for full color) and fabrication costs that are estimated to be 2-3x lower than SRG waveguides of comparable specification. We also offer a common technology for implementing eye tracking and other sensors.
ZB: Holographic optical elements have been used in older augmented reality headset prototypes. Why do you think it was not adopted and how do you plan on increasing adoption for this technology?
JW: Despite its long history, holography display manufacture has been seen as something of an art, involving a material that is complex, difficult and time-consuming to process and prone to image artefacts such as haze.
Developments by Luminit, Zebra Imaging (demonstrating mass production capability), Akonia (leveraging developments in holographic storage and now DigiLens with its advanced holographic polymer materials have elevated holographic gratings to an engineering solution with the potential to rival and indeed exceed the capabilities of SRGs.
SRGs waveguides have gained a head-start thanks to the use of existing mature etching and lithography capability developed for the semiconductor industry. However, cost remains a barrier with yields persistently low. Yield improvement is a key goal for SRG waveguide developers. However, the demand for higher FOV translates to even more complex SRG profiles putting further pressure on yield.
In contrast, our printing process is relatively robust against tighter specifications; unlike SRGs a higher specification holographic grating does not present any additional manufacturing issues after initial mastering has been completed.
Haze was a challenge in early version of LC polymer material system, but thanks to material improvement and more uniform grating morphologies we have now reduced it to a level that is perfectly acceptable for most AR applications.
Holographic waveguides are a good fit to lasers which are already being considered for AR displays particularly AutoHUDs; SRGs require broader bandwidth sources for color balancing.
ZB: People mainly think of headsets when talking about augmented reality. Do you target other applications? What would be the benefits of your technology for those?
JW: It is certainly wrong to limit AR to headsets. Recognising that AR can contribute to any human activity, we are addressing all AR displays with our MonoHUD (MotoHUD for motorcycle helmets) EyeHUD and AR HUD products. Our AeroHUD developed in partnership with Rockwell Collins has been in manufacture for some time. Unlike competing waveguide technologies, we are economically scalable to large area display application such as AutoHUD and retail displays which which would be prohibitively expensive to manufacture using other waveguide technologies.
DigiLens MonoHUD: 5-hour operation and $499 price – an AR waveguide display enabling “Smart Helmet” applications
(Source: courtesy of DigiLens)
ZB: The hype for augmented reality seems to have lowered a bit and the envisioned mass adoption does not seem to have happened. How would you explain that and how do you see this trend changing in the coming years?
JW: It is clear to early adopters of AR headsets that the clunky form factor, poor FOV and generally inadequate image quality of current products falls short of the vision presented by developers and the displays media. True AR is some way off and will need FOV in excess 80 degrees and seamless integration of eye trackers and dynamic lenses for foveated rendering and focal depth. This will be solved partly by continuing technological innovations and more-consumer orientated product design – making the entry of Apple into the market a welcome development.
The biggest challenge is getting the cost of waveguide displays with the required functionality down to the level of a high-end smartphone.
Although we will have to wait for the complete realization of consumer AR, our HUD motorcycle has shown that a subset of AR capabilities can provide a massive benefit. Likewise, we see immediate opportunities in the enterprise sector where form factor and styling is not as critical.
ZB: What is DigiLens’ business model? Will you be a manufacturer, service company or just licensing technologies?
JW: We license our waveguide technology, including materials, copy machines, reference designs and tools, to experienced display OEMs in automotive enterprise and consumer applications to accelerate their optical waveguide products to market.
Our suite of support products including optical design tools, manufacturing tools and parts and material supply.
As our support capability is limited, we limit applications customization strictly on a corporate business-to-business basis.
ZB: What is the current commercial status? Do you already have some traction from major customers?
JW: Our first personal waveguide display, MotoHUD, has been developed for motorcycle applications in collaboration with BMW. A two-waveguide monocular designed to be permanently fitted into a helmet, the display provides full color, nHD resolution with 25-degree FOV (105-degree see through FOV) and maximum brightness 5000 nits. It will be supplied in volume by Young Optics of Taiwan, a world leading display manufacturer. The motorcycle application will provide a springboard for other applications based on the same monocular HUD design.
The automotive industry could be one of our first big adopters. Global revenue from sales of automotive HUDs alone will reach $18.6 billion annually, according to the IHS Automotive Display Market Tracker and Components Forecasts and Analysis. This means we could see new automotive models emerging with HUD safety features before too long. DigiLens has joined forces with Continental to develop an AutoHUD with a 20dgree FOV (demonstrated at CES 2018). which essentially doubles the FOV of the current refractive solution one-sixth of the previous component volume.
In partnership with Rockwell Collins DigiLens has developed the waveguide display for the HGS 3500 Head-up Guidance System for commercial aircraft. The wide field of view HUD is smaller, lighter and more affordable than competitive systems. The first customer to install and certify the equipment is Embraer, a leading manufacturer of commercial, business, and defence aircrafts and technology.
ZB: What is the status in terms of manufacturing?
JW: Our best in class holographic photopolymer (as measured by index modulation) and contact-copy waveguide manufacturing process, is the result of fourteen years of R&D, simplifying classical holography into a photocopy like process. Initially designed for pilot plant operation, our process is being scaled up for full consumer volume manufacture in collaboration with partners such as Young Optics. In addition to the new two-layer display that replaces the original three-layer design, DigiLens has recently announced that it has started using a new inkjet coating manufacturing process with significantly increased throughput.
MonoHUD and Eye HUD are scheduled to enter low rate product at the end of 2018. Our AR headset (ArHUD) will enter low rate production in the middle of 2019. AeroHUD is currently in licensed manufacturer production, while AutoHUD will enter licensed manufacture production in 2020
We believe that our lower plant cost, ease of configuration, scalability, high throughput and yields and the ability to bring the entire process under one roof will transform the economics of waveguide manufacture, allowing manufacturers to produce thin, high quality smart eyewear DigiLens optics, faster and more affordably than ever before.
ZB: What is you focus for the next 12 months?
JW: Our main objectives are getting MonoHUD, EyeHUD, ArHUD through low rate production phase in readiness for licensed manufacturer production. This includes improvements to our image quality measurement systems and quality control. We are also considering single layer full color architecture.
Dr. Jonathan Waldern completed his PhD. Scholarship in virtual reality at the Loughborough University of Technology under the United Kingdom’s advance computing initiative. He founded VIrtuality Inc., a pioneer in VR training and entertainment. Following a successful IPO, he emigrated to California to redress the deficiencies of classical optics for wearable displays, founding DigiLens, Inc. in 2003 under the name SBG Labs. In 2015, the company was renamed from its “Switchable Bragg Grating” technology to DigiLens, its ever-popular brand. A named inventor on over 70 patents, Jon is also the recipient of three national small business awards for innovation, manufacturing and management.
As a Technology & Market Analyst, Displays, Zine Bouhamri, PhD is a member of the Photonics, Sensing & Display division at Yole Développement (Yole). Zine manages the day to day production of technology & market reports, as well as custom consulting projects. He is also deeply involved in the business development of the Displays unit activities at Yole. Previously, Zine was in charge of numerous R&D programs at Aledia. During more than three years, he developed strong technical expertise as well as a detailed understanding of the display industry. Zine is author and co-author of several papers and patents. Zine Bouhamri holds an Electronics Engineering Degree from the National Polytechnic Institute of Grenoble (France), one from the Politecnico di Torino (Italy), and a Ph.D. in RF & Optoelectronics from Grenoble University (France).
Technological reality is piercing the hype for virtual and augmented realities, reminding everyone about all the challenges that are yet to be overcome. – Get more here