Introduction

At AWE 2024, I was on a panel discussion titled “The Current State and Future Direction of AR Glasses.” Jeri Ellsworth, CEO of Tilt Five, Ed Tang, CEO of Avegant, Adi Robertson, Senior Reporter at The Verge, and I were on the panel, with Jason McDowell, The AR Show, moderating. Jason McDowell did an excellent job of moderation and keeping the discussion moving. Still, with only 55 minutes, including questions from the audience, we could only cover a fraction of the topics we had considered discussing. I’m hoping to reconvene this panel sometime. I also want to thank Dean Johnson, Associate Professor at Western Michigan University, who originated the idea and helped me organize this panel. AWE’s video of our panel is available on YouTube.

First, I will outline what was discussed in the panel. Then, I want to follow up on small FOV optical AR glasses and some back-and-forth discussions with AWE Legend Thad Starner.

Outline of the Panel Discussion

The panel covered many topics, and below, I have provided a link to each part of our discussion and added additional information and details for some of the topics.

• 0:00 Introductions
• 2:19 Apple Vision Pro (AVP) and why it has stalled. It has been widely reported that AVP sales have stalled. Just before the conference, The Information reported that Apple had suspended the Vision Pro 2 development and is now focused on a lower-cost version. I want to point out that a 1984 128K Mac 1 adjusted for inflation would cost over $7,000 adjusted for inflation, and the original 1977 Apple 2 4K computer (without a monitor or floppy drive) would cost about $6,700 in today’s dollars. I contend that utility and not price is the key problem with the AVP sales volume and that Apple is thus drawing the wrong conclusion.
• 7:20 Optical versus Passthrough AR. The panel discusses why their requirements are so different.
• 11:30 Mentioned Thad Starner and the desire for smaller FOV optical AR headsets. It turns out that Thad Starner attended our panel, but as I later found out, he arrived late and missed my mentioning him. Thad, later questioned the panel. In 2019, I wrote the article FOV Obsession, which discussed Thad’s SPIE AR/VR/MR presentation about smaller FOV. Thad is a Georgia Institute of Technology professor and a part-time Staff Researcher at Google (including on Google Glass). He has continuously worn AR devices since his research work at MIT’s media lab in the 1990s.
• 13:50 Does “tethering make sense” with cables or wirelessly?
• 20:40 Does an AR device have to work outside (in daylight)?
• 26:49 The need to add displays to today’s Audio-AI glasses (ex. Meta Ray-Ban Wayfarer).
• 31:45 Making AR glasses less creepy?
• 35:10 Does it have to be a glasses form factor?
• 35:55 Monocular versus Biocular
• 37:25 What did Apple Vision Pro get right (and wrong) regarding user interaction?
• 40:00 I make the point that eye tracking and gesture recognition on the “Apple Vision Pro is magical until it is not,” paraphrasing Adi Robertson, and I then added, “and then it is damn frustrating.” I also discuss that “it’s not truly hands-free if you have to make gestures with your hands.”
• 41:48 Waiting for the Superman [savior] company. And do big companies help or crush innovation?
• 44:20 Vertical integration (Apple’s big advantage)
• 46:13 Audience Question: When will AR glasses replace a smartphone (enterprise and consumer)
• 49:05 What is the first use case to break 1 million users in Consumer AR?
• 49:45 Thad Starner – “Bold Prediction” that the first large application will be with small FOV (~20 degrees), monocular, and not centered in the user’s vision (off to the ear side by ~8 to 20 degrees), and monochrome would be OK. A smartphone is only about 9 by 15 degrees FOV [or ~20 degrees diagonally when a phone is held at a typical distance].
• 52:10 Audience Question: Why aren’t more companies going after OSHA (safety) certification?

Small FOV Optical AR Discussion with Thad Starner

As stated in the outline above, Thad Starner arrived late and missed my discussion of smaller FOVs that mentioned Thad, as I learned after the panel. Thad, who has been continuously wearing AR glasses and researching them since the mid-1990s, brings an interesting perspective. Since I first saw and met him in 2019, he has strongly advocated for AR headsets having a smaller FOV.

Thad also states that the AR headset should have a monocular (single-eye) display and be 8—to 20 degrees on the ear side of the user’s straight-ahead vision. He also suggests that monochrome is fine for most purposes. Thad stated that his team will soon publish papers backing up these contentions.

In the sections below, I went from the YouTube transcript and did some light editing to make what was said more readable.

My discussion from earlier in the panel:

11:30 Karl Guttag – I think a lot of the AR or Optical see-through gets confabulated with what was going on in VR because VR was cheap and easy to make a wide field of view by sticking a cell phone with some cheap Optics in front of your face. You get a wide field of view, and people went crazy about that. I made this point years ago on my blog [2019 article FOV Obsession] was the problem. Thad Starner makes this point: he’s one of our Legends at AWE, and I took that to heart many years ago at SPIE AR/VR/MR 2019.

The problem is that as soon as you say beyond about 30-degree field of view, even projecting forward [with technology advancements], as you go beyond 30-degree field of view, you’re in a helmet, something looking like Magic Leap. And Magic Leap ended up in Nowheresville. [Magic Leap] ended up with 25 to 30% see-through, so it’s not really that good see-through, and yet it’s not got the image quality that you would get of an old display shot right in your eyes. You might you could get a better image on an Xreal or something like that.

People are confabulating too many different specs, so they want a wide field of view. The problem is as soon as you say 50 degrees and then you say, yeah, and I need like spatial recognition, I want to do SLAM, and I want to do this, and I want to do that. You’ve now spiraled into the helmet. I mean, you know, Meta was talking the other day about the other panels and said they’re looking at about 50 grams [for the Meta Ray Bans], and my glasses are 23 grams. You’re out of that as soon as you say 50-degree field of view, you’re over 100 grams and and and and and heading to the Moon as you add more and more cameras and all this other stuff, so I think that’s one of our bigger problems whereas AR really Optical AR.

The experiment we’re going to see played out because many companies are working on adding displays to to so called AI audio glasses. We’re going to see if that works because companies are getting ready to make glasses that have 20—to 30-degree field of view glasses tied into AI and audio stuff.

Thad Starner’s comments and the follow-up discussion during the Q&A at the end of the panel:

49:46 Hi, my name is Thad Starner. I’m Professor Georgia Tech. I’m going to make a bold prediction here that the future, at least the first system to sell over a million units, will be a small field of view monocular, non-line-of-sight display, monochrome is okay now; the reason I say that is number one I’ve done different user studies in my lab that we’ll be publishing soon on this subject but the other thing is that you know our phones which is the most popular interface out there are only 9 degrees by 16 degrees field of view. Putting something outside of the line of sight means that it doesn’t interrupt you while you’re crossing the street or driving or flying a plane, right? We know these numbers, so between 8° and 20 degrees towards the ear and plus or minus 8 degrees, I’m looking at Karl [Guttag] here so he can digest all these things.

Karl – I wrote a whole article about it [FOV Obsession]

Thad – And not having a pixel in line of sight, so now feel free to pick me apart and disagree with me.

Jeri-  I want to know a price point.

Thad, I think the first market will be captioning for the heart of hearing, not for the deaf. Also, possible transcription, not translation; at that price point, you’re talking about making reading glasses for people instead of hearing aids. There’s a lot of pushback against hearing, but reading glasses people tend to do, so I’d say you’re probably in the $200 to $300 range.

Ed – I think your prediction is spot on, minus the color green. The only thing I think is that it’s not going to fly.

Thad – I said monochrome is okay.

Ed – I think the monocular field of view is going to be an entry-level product, and you see, I think you will see products that will fit that category with roughly that field of view with roughly that offset angle [not in the center of view] is what you’re going to see in the beginning. Yeah I agree with that but I don’t I think that’s the first step I think you will see a lot of products after that that’s going to do a lot more than monocular monochrome offset displays, start going to larger field of view binocular I think that will happen pretty quickly.

Adi – It does feel like somebody tries to do that every 18 months, though, like Intel tried to make a pair of glasses that did that. It’s a little bit what North did. I guess it’s just a matter of throwing the idea at the wall because I think it’s a good one until it takes.

I was a little taken aback to have Thad call me out as if I had disagreed with him when I had made the point about the advantages of a smaller FOV earlier. Only after the presentation did I find out that he had arrived late. I’m not sure what comment I made that made Thad think I was advocating for a larger FOV in AR glasses.

I want to add that there can be big differences between what consumers and experts will accept in a product. I’m reminded of a story I read in the early 1980s when there was a big debate between very high-resolution monochrome versus lower-resolution color (back then, you could only have one or the other with CRTs) that the head of IBM’s monitor division said, “Color is the least necessary and most desired feature in a monitor.” All the research suggested that resolution was more important for the tasks people did on a computer at the time, but people still insisted on color monitors. Another example is the 1985 New Coke fiasco, in which Coke’s taste studies proved that people liked New Coke better, but it still failed as a product.

In my experience, a big factor is whether the person is being trained to use the device for enterprise or military use versus whether the user is buying it for their own enjoyment. The military has used monochrome displays on devices, including night vision and heads-up displays for decades. I like to point out that the requirement can change if “If the user paid to use versus is paying to use.” Enterprises and the military care about whether the product gets the job done and pay someone to use the device. The consumer has different criteria. I will also agree that there are cases where the user is motivated to be trained, such as Thad’s hard-of-hearing example.

Conclusion on Small FOV Optical AR

First, I agree with Thad’s comments about the smaller FOV and have stated such before. There are also cases outside of enterprise and industrial use where the user is motivated to be trained, such as Thad’s hard-of-hearing example. But while I can’t disagree with Thad or his studies that show having a monocular monochrome image located outside the line of sight is technically better, I think consumers will have a tougher time accepting a monocular monochrome display. What you can train someone to use differs from what they would buy for themselves.

Thad makes a good point that having a biocular display directly in the line of sight can be problematic and even dangerous. At the same time, untrained people don’t like monocular displays outside the line of sight. It becomes (as Ed Tang said in the panel) a point of high friction to adoption.

Based on the many designs I have seen for AR glasses, we will see this all played out. Multiple companies are developing optical see-through AR glasses with monocular green MicroLEDs, color X-cube-based MicroLEDs, and LCOS-based displays with glass form-factor waveguide optics (both diffractive and reflective).