Introduction

Two recent LinkedIn articles by Axel Wong inspired this article. The first, Decoding the Optical Architecture of Meta’s Next-Gen AR Glasses: Possibly Reflective Waveguide—And Why It Has to Cost Over $1,000, discussed the use of reflective/geometric (Lumus, or a Lumus Clone) Waveguides using an LCOS display in Meta’s Hypernova AR/AI glasses. Axel’s article was partially based on information from an article by Bloomberg’s Mark Gurman and on information he gleaned from a supplier in China. Axel’s second article, Google’s New AR Glasses: Optical Design, Microdisplay Choices, and Supplier Insights, said that the Google AR glasses were shown in a recent TED Talk by Shahram Izadi, which likely used a diffractive waveguide by Applied Materials.

Shahram Izadi, of Google, held up an optical engine in the video that he said was full color. Axel’s article on the Google AI/AR glasses speculated that it uses either LCOS or an X-Cube MicroLED engine, but seemed to favor it being LCOS. Axel also wrote that the waveguide was likely from Applied Materials. As will be discussed, I think that it is highly likely that Google’s AR glasses are using Avegant’s 20-degree LCOS optical engine that they presented at SPIE’s AR/VR/MR 2025.

The Meta and Google AR/AI glasses have some major similarities: they are both monocular (single display for the right eye), use a Full Color LCOS MicroDisplay, and use waveguides. It has been reported that Meta is putting the display in the lower right corner of the user’s view, whereas it appears from Google’s TED talk that the display is roughly in the center vertically. Perhaps the biggest difference is that Meta is likely using a Lumus reflective waveguide, perhaps with a 30° FOV, whereas Google is using a diffractive waveguide with likely a 20° FOV.

This blog has a tradition of identifying technology inside Google’s AR glasses. Back in February 2013, I correctly identified a Himax LCOS device in the original Google Glass. Stock market analyst Mark Gomes wrote an article on Seeking Alpha based on my findings, causing Himax’s stock to jump by $223 M. See my 2013 article Google Glass and Himax Whirlwind.

SID Display Week This Week

I’m off to SID Display Week this week. If you have a product or concept or want to discuss a topic from this blog at Display Week 2025, please email me at meet@kgontech.com. I’m planning on being there every day of the exhibits (May 13-15), but my calendar is getting pretty full. I may also have time to meet before the exhibition on Monday, May 12th. I’ve partnered with SID to share my insights from Display Week (DW) — past, present, and future. If you’re planning to attend Display Week, SID has provided the code DW25KARL for a free exhibit hall pass.

Disclaimers

While I contacted Lumus and Avegant in preparation for this article, neither company said they could not comment. Therefore, this article is based on the available public evidence, including that provided in Axel Wong’s articles and Bloomberg’s Mark Gurman’s article on Meta Hypernova, plus other sources and my experience. While I think I am correct, I’m not 100% sure.

I should also note that while Meta’s Hypernova is expected to be a product for sale in 2025, it is unclear whether the Google AR glasses are anything more than a lab prototype or perhaps a reference design and developer platform for their Android XR partners.

I should also point out that I have not had a chance to evaluate either Meta’s Hypernova or Google’s XR Glasses. Having followed Lumus’s and Avegant’s developments, I have some idea of what the images may look like, but I have not seen the complete designs.

Both Meta and Google AR Glasses Monocular and LCOS

Meta and Google’s devices are strikingly similar in that they are both Monocular (single-eyed) and likely use LCOS as the display device.

The Case For Monocular

The most obvious reasons to go monocular are to save on cost and weight. Another advantage is that there is no need for IPD adjustment. Mark Gurman has further written that the display is in the “lower right corner of the right lens.”

Long-time AR glasses user, researcher, and Google advisor Thad Starner has advocated for a monocular display on the lower outside (discussed in AWE 2024 Panel: The Current State and Future Direction of AR Glasses), exactly what Meta Hypernova appears to be doing. The advantage of the lower outside corner for the virtual image is that it keeps it out of the way of the user’s forward vision. Thad makes the point that you don’t want a message popping up and blocking your vision at a critical time. From a human factors point of view, if the display is not going to be centered horizontally, then it is best to have it below center, as humans can look down much more easily than look up.

Having biocular displays pretty much forces them to be in the center, but they could be in the lower half if there is a worry of blocking forward vision. Still, if they are not in the center of the forward view, it will be uncomfortable to use for long periods, and the wearer will obviously be looking down. So I would expect that if, as Gurman’s article stated, Meta was planning on a biocular Hypernova 2, they would center the virtual image in the user’s forward view.

LCOS – Why not MicroLEDs?

With all the discussion about MicroLEDs for AR glasses today, it may seem strange that both Meta and Google use LCOS. There are many sound technical reasons for choosing LCOS, particularly for a full-color display, including:

• Cost and availability—MicroLEDs today are much more expensive, and supplies are very limited and likely to remain so for at least the next few years.
• Efficiency—As I discussed in SID Display Week 2024 – LCOS, LCOS has a major endurance advantage that makes it much more efficient with waveguides (diffractive or reflective).
  • For a full white screen, LCOS displays illuminated by LEDs are very roughly 10x more power efficient than MicroLED with waveguides. MicroLEDs have the advantage that their power consumption is roughly proportional to the average pixel value (AVP), so if there is “sparse content” like text and simple symbols only on a clear/black background, then the AVP is low and their power can be low.
  • Red MicroLEDs are very inefficient, and Blue MicroLEDs, while necessary for color balance, provide almost no “nits.” Thus, a full-color MicroLED display takes well more than 2x the power of a green-only display for the same output to the eye “white nits.” Color compounds the problem with etendue efficiency and is particularly bad with spatial color (side by side R,G,B) where the emission area is larger.
• Viewfinder, Web Browsing, and Picture-based Applications give LCOS a huge power advantage. If the glasses are to support any content, including white screens or looking at bright scenes, they have to be designed for the worst-case conditions, including mostly white/bright images. While most of the content might be between 5% and 20% AVP, if glasses are to work in all cases, they have to be designed for 100% AVP if they are going to support any possible content.
  • As I often say, “In AR headsets, Amateurs worry about battery life, pros worry about power dissipation.” Supporting the worst-case power consumption in AR glasses is a massive issue, as there is very little in the way of surfaces that can dissipate heat.
• Useable in daylight—AR glasses should output 2,000 or more nits to the eye in daylight to be usable outdoors. Once again, this favors LCOS unless the content is very sparse.
• “Bright mode” LCOS illumination: Some companies have the option to sacrifice color accuracy or switch to black-and-white mode to boost brightness.

For many of the reasons above, while LCOS does not get the media attention and corporate investment of MicroLEDs, it is likely to remain the best option for full-color AR headsets for some time (perhaps a long time).

Meta’s and Google’s Roadmaps for LCOS versus MicroLED or LBS

The chart below on the left was presented by Meta’s Hartlove at Display Week 2024 and SID AR/VR/MR 2025. Their chart shows LCOS as the “Ready Technology,” MicroLEDs as the “Anticipated Technology,” and Laser Scanning as the “Final Solution” (with a question mark). Below right is a 2023-04-27 SPIE AR/VR/MR fireside chat slide interviewing Trilite, presented by Bernard Kress of Google, that contrasts very dramatically. Kress’s slide shows power efficiency versus Average Pixel Lit (same as AVP); similar to my comment above, Kress shows the MicroLED/LCOS power crossover at ~12% AVP (not true today for full color, maybe in the future), but then he shows that with “MiniLED local dimming” the crossover could move out dramatically. It’s also notable that Kress, when he was a technical leader on Microsoft HoloLens, worked with laser scanning on the HoloLens 2.

Thus, we seem to have highly contrasting views on the future of AR display technology. A cynical person might suggest that Hartlove’s roadmap may be meant to entice Meta’s management to invest in their R&D programs, more than it is tied to business reality. Kress’s (Google) chart may reflect the scars from his work on HoloLens 2.

Meta’s Hypernova Optics – Likely a Lumus Z-Lens Variant

I used some information published by Axel on Reddit in October 2024 in my article, Meta Orion AR Glasses (Pt. 1 Waveguides). In that same Reddit article, Axel wrote (with my bold highlighting):

There were rumors before that Meta would launch new glasses with a 2D reflective (array) waveguide optical solution and LCoS optical engine in 2024-2025. With the announcement of Orion, I personally think this possibility has not disappeared and still exists. After all, Orion will not and cannot be sold to ordinary consumers. Meta may launch another reduced-spec version of reflective waveguide AR glasses for sale, which is still an early adopter version for developers or geeks, but it is speculated that this reflective waveguide version is also likely to be a transition, and will eventually return to surface relief grating (SRG) diffraction waveguides.

It seems to be a bit of an open secret, at least in China, that Meta is likely using a Lumus reflective waveguide in a prototype, if not a final product. I have seen several Chinese companies try to copy Lumus’s reflective waveguides over the years, and the image quality has not been very good compared to Lumus’s. Furthermore, I can’t see why Meta would risk a patent challenge from Lumus if they went with a copy (these points are also made in Axel’s LinkedIn article).

I have been following Lumus’s progress since before I started this blog in 2011. In January at SPIE AR/VR/MR 2025, I met with Lumus to see their newly announced Z30 30° FOV Z-Lens at SPIE AR/VR/MR. They were using a 720 x 720 pixel LCOS microdisplay.

I should note that the Z30 waveguide I have seen had the display centered vertically and was part of a binocular design. The image was not below center or off to the right, as Bloomberg’s Mark Gurman’s Hypernova article reported. And thus, it was not exactly the Z30, but a customized version.

Shown below, left is the 30° Z30 waveguide with the attached projector engine with its older Maximus and Z50 50° waveguides. While the Maximus and Z50 are further away, you should be able to tell that the Z30 projector engine is much smaller. Lumus, in their January announcement, said the Z30 prototype outputs to the eye are>3,000 Nits/Watt_LED, and Lumus told me that they expect to more than double this efficiency with design improvements. [See my Caution on Using Nits/Watt_LED in the Appendix, as they are not comparable between companies]

Above right is a quick handheld picture I took through the Z30; I doubt I had the camera aligned well (I was holding the glasses in one hand and the camera in the other), and the background was not solid black (the background is causing uniformity variation). Still, the color uniformity is much better than that of the typical diffractive waveguide.

High transparency and very little eye glow

I missed getting a picture of myself wearing the Z30-based glasses, which have smaller projectors and frames. The picture below is of me wearing the Z50 (50-degree) prototypes. The Z50 and Z30 have only very slight “eye glow” and are about 90% transparent. The very slight eye glow that is seen in the pic is for a nearly full white bright image, and not a typical image.

Lumus Waveguide With Prescription Correction

A key issue for any consumer AR glasses is to incorporate prescription correction. Lumus’s Z-Lens waveguides propagate TIR light in the waveguide at a shallower angle than diffractive waveguides, which enables not only the use of significantly lower index of reaction glass, but also the direct bonding of push-pull lenses to change the virtual image focus distance and prescription correction.

Due to surface features and to maintain TIR, diffraction-type waveguides require an air gap. This adds complexity and makes the combination of lenses and waveguides thicker. Having surfaces with an air gap means there are additional surfaces that can cause ghosts and require anti-reflective coatings to reduce them. There is not enough information available to determine whether the Google XR Glasses with diffraction waveguides will address prescription correction.

Lumus has partnered with AddOptics to provide the push-pull lenses that incorporate prescription correction. Lumus demonstrated the combination to me at AWE 2024.

Lumus Wide (70°) FOV in Glass (Versus Silicon Carbide)

Meta’s Orion AR Glasses demonstration in late 2024 used very expensive/hard-to-manufacture Silicon Carbide (SiC) Waveguides. As discussed in Meta Orion AR Glasses (Pt. 1 Waveguides), they used SiC because of its high index of refraction, which is required to support a 70-degree FoV with diffractive waveguides. At AR/VR/MR 2025, Lumus was claiming that, due to the shallower TIR angle of the Z-Lens, they can support a 70° with their glass waveguides.

What about the rumored $1,000-$1400 Price?

I’ve seen many negative comments about Meta’s Hypernoval’s rumored price range of $1,000 to $1,400. As I wrote about the Apple Vision Pro, People Who Say the AVP’s $3,499 price is too high lack historical perspective. I’m not as worried about the price as I am about the functionality and usefulness. If the product is useful and finds a market, there is no reason that the cost should not be reduced significantly. The price reflects that Hypernova is testing the waters more than a full-blown consumer product.

Google XR Prototype (At Ted Talk)

Alex Wong’s LinkedIn article on the Google XR TED talk strongly suggested that Google is using waveguides from both Applied Materials (AMAT) and “one based in Shanghai, China.” In his article, Alex was unsure about the optical engine. As will be discussed, I believe Avegant designed the optical engine based on its size and shape (to be discussed below), and due to the recent partnership between AMAT and Avegant.

In their respective presentations at AR/VR/MR 2025, both Avegant and AMAT discussed their new partnership. Avegant presented several slides discussing their new 20° FOV monocular LCOS engine in a development kit jointly developed with AMAT.

Below are the Avegant/AMAT development kit X-ray diagram (top) and a still frame (bottom) from Google’s video showing an exploded view of their XR glasses. They are remarkably similar. I have also added an inset of just the optical engine part of Avegant’s development kit near Google’s optical engine. While the projector portion may look bent in the Google exploded view, this may be simple due to the arrangement of the electrical components around the optics to fit Google’s frames better.

On both diagrams above, the projector is on the side of the right eye (left side of the diagram). Avegant’s diagram shows microphones on the side of the left eye, whereas Google’s diagram has a hole for a camera. I’m a big believer that a camera is going to be essential for any “AR with AI” glasses. The location of the image on one side and the camera on the opposite side of the frames, while it makes sense in terms of fitting them into the frame, is poor in terms of using the display as a camera viewfinder due to parallax.

I have added labels pointing to some of the components in Google’s design. They appear to have a set of push-pull lenses on either side of the waveguide, but I don’t know if they have or will support prescription correction. All in all, it looks like Google took the Avegant and AMAT development kit and then modified it slightly to fit their needs.

I have taken information from two slides with some specs presented by Avegant at AR/VR/MR 2025 below. As I will caution in the appendix, you can’t objectively directly compare the Nits/Watt_LED numbers between Avegant and Lumus shown earlier. Lumus’s Z30 has ~2.25x the FOV area (30/20-squared) plus many other factors. What you can see is that the Nits/Watt_LED falls off dramatically with brightness. For 600Nits/23mW_LED = 25,000 Nits/Watt_LED, whereas 3000 Nits/226mW = 11,272 Nits/Watt_LED or less than half the efficiency.

These efficiency numbers on the surface seem very good/high for a diffractive waveguide, even with the comparatively small FOV. Avegant makes a point that they have made significant efforts to make their optical engine very efficient.

Avegant has devised clever ways to reduce the size of its LCOS projector engines. It seems that every year at AR/VR/MR, Avegant presents an ever-smaller engine. The optical path (taken from Avegant’s website) from their newer projectors is shown below. A key trick is how they use a dichroic combiner/”waveguide” to route light down the projector lens to avoid needing a polarizing beam splitter in traditional LCOS projector engines.

Meta Hypernova and Google XR — Are they products, developer systems, or prototypes?

We are seeing many product concepts in AR glasses, such as Meta’s Orion, developer devices such as Snap Spectacles 5, and products from many companies.

Meta’s Hypernova appears to be a high-end, limited-volume consumer product to test the market. Based on how Hypernova is received, Meta could either focus on driving volume to reduce cost or focus on the (rumored) biocular Hypernova 2. Meta is highly unlikely to bring Orion’s Silicon Carbide to the mainstream market in the next several years. Still, Meta is clearly serious about AR glasses and plans to spend about $20B this year on AR and VR, with the bulk of the investment going into AR.

Google’s intention for its AR glasses is much less clear. Google has developed a reputation for entering and exiting markets, particularly when it comes to hardware. It’s not clear whether Google will build a hardware product itself or leave it to one of its Android XR partners; in this case, the Google AR glasses shown in the TED Talk might be a reference design for their partners.

Conclusions

One thing is for sure: the glasses form factor space is heating up, with the giants Meta and Google starting to show products that are likely to be sold to consumers in the next six months to a year. Rumors of Apple entering the Optical See-Through AR fray are also starting to heat up again.

LCOS still has major physics advantages over MicroLEDs with waveguides when displaying full-color images, such as those from camera viewfinders, photographs, or web browsing. This is particularly true when trying to achieve the 1,000 to 3,000 nits to the eye necessary for practical use in daylight. While MicroLEDs seem to garner most of the attention, and while there are drawbacks to LCOS due to field sequential color breakup and less contrast, LCOS is likely to be the most practical display technology for full-color or higher resolution for at least the next few years and perhaps for many years.

One thing I don’t understand is why Lumus and Avegant are still independent companies, given the numerous acquisitions of companies in the AR space over the last ten years. I have seen massive spending and acquisitions in the area of MicroLED displays by Meta, Google, and Apple. Yet, almost nothing has happened beyond Snap buying the struggling Compound Photonics in LCOS.

Appendix: Caution on comparing nits/Watt_LED with different Waveguides

Both Lumus and Avegant have given Nits/Watt_LED specs for their projector and waveguide combinations. I want to caution everyone that while the numbers give some idea of the efficiency of the projector and optics, there are so many other variables that they are likely not comparable.

While “nits/WattLED” may sound like an objective number, many factors make it impossible to compare numbers that sound the same from different companies. Unfortunately, every company measures differently. These factors include:

• The Field of View—To a first approximation, the Nits/Watt_LED should vary at least proportionally with the square of the FOV as the light is spread out over an area.
• Eye Box Size and Eye Relief—A larger eye box and longer eye relief mean that light will be spread over a larger area, making the Nits/Watt_LED value lower (or higher for a smaller eye box or eye relief).
• Measuring peak value versus average or worst case—Typically, most companies will pick the “peak value” (near the center). Different waveguides have different fall-off toward the periphery. A set of optics that concentrates light in the center will have a higher “peak value,” while being dark in the periphery. In my experience, reflective waveguides are more uniform than diffractive waveguides from the center to the outside. Thus, a “peak” measurement typically favors diffractive waveguides even if both specify the peak value.
• Many factors are non-linear. For example, as the total light output increases due to brightness, a bigger FOV, or an eye-box, the efficiency decreases as the LEDs heat up. This makes it impossible to compare fairly different headsets with different FOV or brightness.
• Full Color versus Green Only—As discussed earlier, nits measure human eye response, and with a color balanced “white,” red and blue contribute relatively few nits while consuming power. Thus, full-color nits are going to be less efficient with the same technology. In the same technology, the full color nits/Watt_LED could be significantly less than one-fourth that of the green-only nits.
• Engineering Trade-off—Depending on the technology, various engineering trade-offs can help or hinder Nits/WattLED. For example, diffractive waveguides might reduce efficiency in improving color uniformity or reducing eye glow.
• Marketing “Fudge” and measuring “cherry-picked” units—Since there are no “marketing police” with testing facilities that will report on measure values over the whole FOV, companies are prone to fudge numbers or use cherry-picked units.

I would not say the numbers are meaningless, and I am still happy that some companies report their Nits/Watt_LED. It at least gives some idea as to whether the AR glasses might work outdoors. The values are probably more comparable within products from the same company than they are between two very different designs.