❌

Normal view

There are new articles available, click to refresh the page.
Before yesterdayMain stream

Mixed Reality at CES & AR/VR/MR 2024 (Part 2 Mostly Optics)

✇KGOnTech
By: Karl Guttag
12 April 2024 at 02:48

Introduction

In part 1, I wrote that I was planning on covering optics and display companies at CES and the SPIE AR/VR/MR conferences in 2024 in part 2 of the video I made with Jason McDowall in this article. However, as I started filling in extra information on the various companies, the article was getting long, so I broke the optics and displays into two separate articles.

In addition to optics companies, I will also be touching on eye track with Tobii, who is doing both optics and eye tracking, and Zinn Labs.

Subscription Options Coming to KGOnTech

Many companies, including other news outlets and individuals, benefit from this blog indirectly through education or directly via the exposure it gives to large and small companies. Many, if not most, MR industry insiders read this blog worldwide based on my conference interactions. I want to keep the main blog free and not filled with advertising while still reporting on large and small companies. To make financial sense of all this and pay some people to help me, I’m in the process of setting up subscription services for companies and planning on (paid) webinars for individuals. If you or your company might be interested, please email subscriptions@kgontech.com.

Outline of the Video and Additional Information

Below is an outline of the second hour of the video, as well as additional comments and links to more information. The times in blue on the left of each subsection below link to the time in the YouTube video discussing a given company.

0:00 Waveguides and Slim Optics

0:03 Schott and Lumus

Schott AG is one of the world’s biggest makers of precision glass. In 2020, Schott entered into a strategic partnership with Lumus, and at AR/VR/MR 2024 and 2023, Lumus was prominently featured in the Schott booth. While Schott also makes the glass for diffractive waveguides, the diffraction gratings are usually left to another company. In the case of the Lumus Reflective waveguides, Schott makes the glass and has developed high-volume waveguide manufacturing processes.

Lumus waveguides consistently have significantly higher optical efficiency (for a given FOV), better color uniformity, better transparency, higher resolution, and less front projection (“eye glow”) than any diffractive waveguide. Originally, Lumus had 1-D pupil-expanding waveguides, whereas diffractive waveguides were 2-D pupil-expanding. The 1-D expanding waveguides required a large projection engine in the non-expanding direction, thus making the projection optics bigger and heavier. In 2021, Lumus first demonstrated their 2-D expanding Maximus prototype waveguides with excellent image quality, 2K by 2K resolution, and 50° FOV. With 2-D expansion, projection image optics could be much smaller. Lumus has continued to advance its Reflective 2D expanding waveguide technology with the “Z-Lens.” Lumus says that variants of this technology could support more than a 70-degree FOV.

Waveguides depend on “total internal reflection” (TIR). For this TIR to work, diffractive waveguides and earlier Lumus waveguides require an “air gap” between the waveguide surface and any other surfaces, including “push-pull” lenses, for moving the waveguide’s apparent focus distance and vision correction. These air gaps can be hard to maintain and source unwanted reflections. Lumus Z-Lens can be embedded in optics with no air gap (and the first waveguide to make this claim) due to the shallower angles of the TIR reflections.

While Lumus waveguides are better than any diffractive waveguide in almost every image quality and performance metric, their big questions have always revolved around volume manufacturing and cost. Schott thinks that the Lumus waveguides can be manufactured in high volume at a reasonable cost.

Over the last ten years, I have seen significant improvements in almost every aspect of diffractive waveguides from many companies (for example, my articles on DigiLens and Dispelix). Diffractive waveguides are easier, less expensive, and much easier to customize. Multiple companies have diffraction waveguide design tools, and there are multiple fabrication companies.

As I point out in the video, many MR applications don’t need the highest image quality or resolution; they need “good enough” for the application. Many MR applications only need simple graphics and small amounts of text. Many applications only require limited colors, such as red=bad, green=good, yellow=caution, and white or cyan for everything else. While others can get away with monochrome (say green-only). For example, many military displays, including night vision, are often monochrome (green or white), and most aviation HUDs are green-only.

I often say there is a difference between being “paid to use” and ” paying for” a headset. By this, I mean that someone is paid to use the headset to help them be more effective in their job, whereas a consumer would be paying for the headset.

For more on Lumus’s 2-D expanding waveguides:

For more on Schott and Lumus’s newer Z-Lens at AR/VR/MR 2023:

For more on green-only (MicroLED headsets) and full-color MicroLEDs through diffractive and Lumus reflective waveguides, see:

4:58 Fourier (Metasurface)

Fourier is developing metasurface technology to reflect and redirect light from a projector in the temple area of AR glasses to the eye. If a simple mirror-type coating were placed on the lens, projected light from the temple would bounce off at an angle that would miss the eye.

Multiple companies have previously created holographic Optical Elements (HOEs) for a similar optical function. Luminit developed the HOE used with North Focals, and TruLife Optics has developed similar elements (both Luminit and TruLife’s HOEs are discussed in my AWE 2022 video with Brad Lynch).

Fourier’s metasurface (and HOEs) can act not only as a tilted flat mirror but also as a tilted curved mirror with “optical power” to change magnification and focus. At least in theory (I have not seen it, and Fourier is still in development), the single metasurface would be simpler, compact, and have better optical efficiency than birdbath optics (e.g., Xreal and many others) and lower cost and with much better optical efficiency than waveguides. But while the potential benefits are large, I have yet to see a HOE (or metasurface) with great image quality. Will there, for example, be color uniformity, stray light capture, and front projection (“eye glow”) issues as seen with diffractive waveguides?

Laser beam scanning with direct temple projection, such as North Focals (see below left), uses a Hologram embedded or on the surface of a lens to redirect the light. This has been a common configuration for the lower resolution, small FOV, and very small eyebox Laser Beam Scanning (LBS) glasses shown by many companies, including North, Intel, and Bosch. Alternatively, LCOS, DLP, MicroLED, and laser beam scanning projectors have used waveguides to redirect the light and increase the eyebox size (the eyebox is the range of movement of the eye relative to the glasses where the whole image can be seen).

Avegant (above right), Lumus, Vuzix, Digilens, Oppo, and many others have demonstrated that with waveguides with DLP, LCOS, and MicroLEDs in very small form factors as HOEs and Metasufaces (see DigiLens, Lumus, Vuzix, Oppo, & Avegant Optical AR (CES & AR/VR/MR 2023 Pt. 8). Still, waveguides are much lower in efficiency, so much so that the use of MicroOLED is impractical with waveguides. In contrast, using MicroOLED displays is possible with HOEs and Fourier’s metalenses. There are also potential differences in how prescription lenses could be supported.

As discussed above, holographic mirrors can also be used to form the equivalent of a curved mirror that is also tilted. The large CREAL3D prototype (below left) shows the two spherical semi-mirrors. CREAL3D planes to replace these physical mirrors with a flat HOE (below right).

Fourier metalens would perform the same optical function as the HOE. We will have to wait and see the image quality and whether there are significant drawbacks with either HOEs or metalenses. My expectation is that both metalenses and HOEs will have similar issues as diffraction gratings.

Some related articles and videos on small form factor optics and Videos.

6:23 Morphonics

Morphontonics has developed methods for making waveguides and similar diffractive structures on large sheets of glass. They can make many small diffractive waveguides at a time or fewer large optical devices. In addition to waveguides, Morphotonics makes a light guide structure for the Leia Lightfield monitor and tablet.

Morphotonics presentation at AR/VR/MR 2023 can be found here: Video of Morphotonics AR/VR/MR 2023 presentation.

From Morphotnics 2023 AR/VR/MR Presentation

10:33 Cellid (Wave Guides)

Cellid is a relatively new entrant in waveguide making. I have seen their devices for several years. As discussed in the video, Cellid has been continually improving its waveguides. However, at least at present, it still seems to be behind the leading diffractive waveguide companies in terms of color uniformity, FOV, and front projection (“eye glow).

11:47 LetinAR

Several companies are using LetinAR’s PinTilt optics in the AR glasses. At CES, JorJin was showing their J8L prototypes in the LetinAR booth. Nimo (as discussed in Mixed Reality at CES and the AR/VR/MR 2024 Video (Part 1 – Headset Companies) was showing their LentinAR-based glasses in their own booth. Sharp featured their LentinAR glasses in their booth but didn’t mention they were based on LetinAR optics.

LetinAR’s optics were also used in an AT&T football helmet display application for the deaf (upper left below).

LetinAR originally developed “pin mirror” optics, which I first covered in 2018 (see CES 2018 in the listings below). The pin-mirror technology has evolved into their current “PinTilt” technology.

While LetinAR has several variations of the PinTilt, the “B-Type” (right) is the one I see being used. They use an OLED microdisplay as the display device. The image light from the OLED makes a TIR (total internal reflection) bounce off the outside surface into a collimating/focusing mirror and then back up through a series of pupil-replicating slats. The pupil replication slats enable the eye to move around and support a larger FOV.

As I discussed in the video, the image quality is much better than with the Pin-Mirrors, but gaps can be seen if your eye is not perfectly placed relative to the slats. Additionally, with the display off, the view can be slightly distorted, which can likely be improved in the manufacturing process. LetinAR also let me know that they are working on other improvements.

LetinAR’s PinTilt is much more optically efficient than diffractive or even Lumus-type reflective waveguides, as evidenced by its use of micro-OLEDs rather than much brighter LCOS, DLP, or micro-LEDs. At the same time, they offer a form factor that is close to waveguides.

Some other articles and videos covering LetinAR:

13:57 Tooz

Tooz was originally spun out of Zeiss Group in 2018, but in March 2023, they returned to become part of Zeiss. Zeiss is an optical giant founded in 1846 but is probably most famous to Americans as the company making the inserts for the Apple Vision Pro.

Tooz’s “Curved Waveguide” works differently than diffractive and Lumus-type reflective waveguides, which require the image to be collimated, use many more TIR light bounces, and have pupil replication. Strictly speaking, none of these are”waveguides,” but the diffractive and Lumus-type devices are what most people in the industry call waveguides.

The Tooz device molds optics and a focusing mirror to move the focus of the display device, which currently can be either a Micro-OLED or, more recently, (green only) Micro-LED. The image light then makes a few TIR bounces before hitting a Fresnel semi-mirror, which directs the light toward the user’s eye (above right). The location of the Fresnel semi-mirror, and thus the image, is not centered in the user’s field of view but slightly off to one side. It is made for a monocular (single-eye) display. The FOV is relatively small with 11- and 15-degree designs.

Tooz’s Curved Waveguide is aimed at data snacking. It has a small FOV and a Monocular display off the side. The company emphasizes the integration of prescription optics and the small and lightweight design, which is optically much more efficient than other waveguides.

Tooz jointly announced just before the AR/VR/MR conference that they were working with North Ocean Photonics to develop push-pull optics to go with waveguides. Tooz, in their AR/VR/MR 2024 presentation, discussed how they were trying to be the prescription optics provider for both their curved waveguides and what they call planar waveguides. One of their slides demonstrated the thickness issue with putting a push/pull set of lenses around a flat waveguide. The lenses need to be thicker to “inscribe” the waveguide due to their curvature (below right).

19:08 Oorym

Oorym is a small startup founded by Yaakov Amitai, a founder and former CTO of Lumus. Oorym has a “waveguide” with many more TIR bounces than Tooz’s design but many less than diffractive and Lumus waveguides. They use a Fresnel light redirecting element. It does not require collimated light and is much more efficient than other waveguides. They can support more than a 50-degree FOV. It is thicker and more diffractive, and Lumus waveguides are in the same order as the thickness of LetinAR. Oorym is also developing a non-head-mounted Heads-Up Display (HUD) device.

Oorym

21:57 Gixel

Gixel’s technology has to be among the most “different” I have seen in a long time. The concept is to have a MicroLED “bar” display with only a single or a few rows of pixels in one direction and with the full horizontal resolution in the other. The “rows” may have full-color pixels or a series of 3 single-color row arrays. Then, a series of pupil-replicating slats rotate to scan the bar/row image vertically synchronously with a time-sequential change of the row display. In this way, the slats scan row display forms a whole image to the eye (and combines the colors if there are separate displays for each color).

They didn’t have a full working prototype, but they did have the rotating slats working.

My first impression is that it has a Steampunk feel to the design. I can see a lot of issues with the rotating slats, their speed and vibration, the time-sequential display, and a mirage of other potential issues. But still, it wins for the sheer audacity of the approach.

23:42 Meta Research (Time Sequential Fixed Foveated Display) & Varjo

From 2017 Article of Varjo

Meta Research presented the concept of a time-sequence fixed-foveated display using single pancake optics. The basic idea is that pancake optics work by making two passes through some of the refractive and mirror optics, which magnifies the display. In a normal pancake, quarter waveplates change the light’s polarization and affect the two passes. A (pixel-less) liquid crystal shutter can act as a switchable quarter waveplate. This way, the display light will make one or two passes through part of the optics to cause two different magnifications. By time sequencing the display with the LC shutter’s switching, both a lower angular resolution but larger image and a higher angular resolution but smaller “foveated” display will be seen by the eye time sequentially.

This basically happens with a single set of optics and a single display, which is what Varjo was doing with their “fixed foveated display,” which used two display devices, optics, and a combining beam splitter.

I like to warn people that when a research group from a big company presents a concept like this to all their competitors at a conference like AR/VR/MR, it is definitely NOT what they are doing in a product.

Fixed (and Eye Tracking) Foveated Displays

In 2017, Varjo was focused on its foveated display technology. Their first prototype had a “fixed foveated display,” meaning the central high-resolution region didn’t move. Varjo claimed they would soon have the foveated display tracking the eye, but as far as I know, they never solved the problem.

It turns out that tracking the eye and moving the display is a seemingly impossible problem to solve with the eye’s saccadic movement, even with exceptional eye tracking. As I like to say, “While eye tracking may know where the eye is pointing, you don’t know what the eye has seen.” Originally, researchers thought that human vision fully blanks with saccadic movement, but later research suggests that it only semi-blanks out vision with movement. Combined with the fact that what a human “sees” is basically a composite of multiple eye positions, making a foveated display that tracks the eye is exceedingly difficult, if not impossible. The problem with artifacts due to eye movement, such as field sequential color breakup, they will tend to appear as flashes that are distracting.

We are seven years since Varjo told me they were close to solving the eye-tracking foveated display. Varjo figured out that about 90% of the benefit of a moving foveated display could be realized with a fixed foveated display near the center of the FOV. They may also have realized that solving the problems with a moving foveated display was more difficult than they thought. Regardless, Varjo has pivoted from being a “foveated display company” to a “high-resolution VR/MR company” aimed primarily at enterprise applications. Pixel sizes and resolution of display devices improved to the point where it is now better to use a higher resolution display than to combine two displays optically.

Eyeway Vision Foveated Display (and Meta)

In 2021, I visited Eyeway Vision, which also worked on foveated displays using dual laser scanning displays per eye. After an acquisition by Meta fell through, Eyeway Vision went bankrupt. Eyeway Vision had a fixed foveated display and sophisticated eye tracking, but it went bankrupt before solving the moving foveated display.

Eyeway Vision’s founder, Boris Greenburg, has recently joined VoxelSensors, and VoxelSensors is looking at using their technology for eye/gaze tracking and SLAM (see Zinn Labs later)

Foveated Display (ex., Varjo) vs. Foveated Rending (ex., Apple Vision Pro)

I want to be clear between foveated rendering, where the display is fixed, and just the level of detail in the rendering changes based on eye tracking, from a foveated display, where a high-resolution sub-display is inset within a lower resolution display. Foveated rendering such as the Apple Vision Pro or Meta Quest Pro is possible, although today’s implementations have problems. However, it may be impossible to have a successful eye-tracking foveated display.

For more on this blog’s coverage of Foveated Displays, see:

32:05 Magic Leap (Mostly Human Factors)

At AR/VR/MR 2024, Magic Leap gave a presentation that mostly discussed human factors. They discussed some issues they encountered when developing the Magic Leap One, including fitting a headset to a range of human faces (below right). I thought the presentation should have been titled “Why the Apple Vision Pro is having so many problems with fitting.”

In 2016, This Blog Caught Magic Leap’s Misleading Video

In showing Magic Leap’s history, they showed a prototype headset that used birdbath optics (above left). Back in 2016, Magic Leap released a video that stated, “Shot directly through Magic Leap technology . . . without the use of special effects or compositing.” I noted at the time that this left a lot of legal wiggle room and that it might not be the same “technology” they would use in the final product, and this turned out to be the case. I surmised that the video used OLED technology. It’s also clear from the video that it was not shot through a waveguide. It appears likely that the video was shot using an OLED through birdbath optics, not with the Waveguide Optics and LCOS display that the Magic Leap One eventually used.

In 2019, Magic Leap sued (and lost to) Nreal (now Xreal), which developed an AR headset using birdbath optics and an OLED display. Below are links to the 2016 article analyzing the Magic Leap deceptive video and my 2020 follow-up article:

36:45 NewSight Reality (Not Really “Transparent” MicroLED)

Sorry for being so blunt, but NewSight Reality’s “transparent” MicroLED concept does not and will not ever work. The basic concept is to put optics over small arrays of LEDs, and similar to pupil replication, the person will see an image. It is the same “physics” as MojoVision’s contact display (which I consider a scam). In fact, NewSight’s prototype has nine MojoVision displays on a substrate (below center)

The fundamental problem is that to get a display of any resolution, plus the optics, the “little dots” are so big that they, combined with diffraction, cause a blurry set of gray dots in a person’s vision. Additionally, the pupil replication effect ends up with a series of circles where you can see the image.

38:55 Other Optics and Eye Tracking

The next section is on other optics and eye tracking. Thanks to Tobii being involved in both, they sort of tie this section together.

39:01 AddOptics

AddOptics developed a 3-D-printed optical mold process. It was founded by former Luxexcel employees (Luxexcel was subsequently acquired by Meta in 2022).

I covered AddOptics last year in CES 2023 (Part 3)—AddOptics Custom Optics. The big addition in 2024 was that they showed their ability to make push-pull optics for sandwiching a waveguide. They showed they could support waveguides that required an air gap or not. As far as I am aware, most, if not all, diffractive waveguides require an air gap. The only waveguide I know of that claims they don’t need an air gap is the newer Lumus reflective-based waveguide (discussed in a previous article). Still, I have not heard of whether AddOptics is working with Lumus or one of Lumus’s customers.

Luxexcel had developed a process to directly 3-D print optics without the need for any resurfacing. This means they need to print very fine layers very precisely, lens by lens. While it means each lens it custom can be custom fit, it also seems to be an expensive process compared to the way prescription lenses are made today. By making “low run” 3-D printed molds (something that Luxexcel could also do), AddOptics would have a lower cost per unit and a faster approach. It would require having a stock of molds, but it would not require a prohibitive number of molds to support most combinations of diopter and cylinder (astigmatism) correction.

42:12 Tobii

Tobii, founded in 2001, has long been known for its eye-tracking technology. Tobii was looking to embed LED illuminators in lenses and was working with Interglass. When Interglass (founded in 2004) went bankrupt in 2020, Tobii hired the key technical team members from Integlass. Meta Materials (not to be confused with Meta, formerly Facebook) acquired the assets of Interglass and is also making a similar technology.

The Interglass/Tobii/Meta-Materials process uses many glass molds to support variations of diopter and cylinder adjustments for prescriptions. The glass molds are injected with UV-cured plastic resin, which, after curing, forms lens blanks/rounds. When molding, the molds can be rotated to set the cylinder angle. The round lens blanks can then be cut by conventional lens fitting equipment.

At 2023’s AR/VR/MR, Tobii demonstrated (left two pictures below) how their lenses were non-birefringent, which is important when working with polarized light-based optics (e.g., Pancake Optics, which Tobii says they can make) and displays (LCDs and LCOS). Tobii has videos on its website that show the lens-making and electronic integrating process (below right).

43:44 Zinn (and VoxelSensors)

Zinn Labs uses a Prophesee event-based camera sensor (Zinn and Prophesee announcement). The Prophesee event camera sensor was jointly developed with Sony. Zinn uses Prophesee’s 320×320 6.3μm pixel BSI (BackSide Illuminated) event-based sensor in a 1/5” optical format.

Event camera pixels work like the human eye in detecting changes rather than the absolute value of each pixel. The pixels are much more complex than a conventional camera sensor, with photodiodes and comparators integrated into each pixel using Sony’s BSI process. Rather than scanning out the pixel value at a frame rate, each pixel reports when it changes significantly (more details can be found in the Prophesee white paper – free, but you have to give an email address). The advantage of the event camera in image recognition is that it tends to filter out/ignore everything that is not changing.

Zinn Labs has developed algorithms that then take the output from the event camera and turn it into where the eye is gazing (for more information, see here).

VoxelSensors (and Zinn Labs)

VoxelSensors has a very different type of event sensor called a “SPAES (Single Photon Active Event Sensor)” that could be used for eye/gaze tracking. Quoting from VoxelSensors:

VoxelSensors leverages its distinctive SPAES (Single Photon Active Event Sensor) technology, allowing the integration of multimodal perception sensors, such as innovative hand and gaze tracking and SLAM, with high precision, low power consumption, and low latency. Fusing these key modalities will enable the development of next-gen XR systems.

As discussed earlier, VoxelSensors also recently hired Eyeway Vision found Boris Greenberg, who has extensive experience in eye/gaze tracking.

VoxelSensors’s SPAES uses a laser scanner to scan the area of interest in a narrow-band infrared laser (where the Prophesee event camera would use IR LED flood illumination) and then detect the laser scanner’s return to the area of interest. With narrow-band filtering to filter out all but the laser’s wavelength, the SPAES is designed to be extremely sensitive (they claim as little as a single photon) to the laser’s return. Like the Prophesee event camera, the VoxelSensors’s SPAES returns the pixel location when an event occurs.

While the VoxelSensor’s pixel is more complex than a traditional sensor, it seems simpler than Prophesee’s event camera pixel, but then VoxelSensor requires scanning lasers versus LED. Both are using event sensors to reduce the computational load. I have no idea at this point which will be better at eye tracking.

VoxelSensors with one or more sets of laser scanners and sensors can detect in three dimensions, which is obviously useful for SLAM but might also have advantages for eye tracking.

For more on Voxel Sensors my 2023 CES article: CES 2023 (4) – VoxelSensors 3D Perception, Fast and Accurate.

44:13 Lumotive (LCOS-Based Laser Scanning for LiDAR)

Lumotive has a technology that uses LCOS devices to scan a laser beam. Today, LiDAR systems use a motor-driven rotating prism or a MEMs mirror to scan a laser beam, resulting in a fixed scanning process. The Lumotive method will let them dynamically adjust and change the scanning pattern.

46:03 GreenLight Optics

I’ve known Green Light Optics since its founding in 2009 and have worked with them to help me with several optical designs over the years. Greenlight can design and manufacture optics and is located in Cincinnati, Ohio. I ran into GreenLight at the Photonics West exhibit following the AR/VR/MR conference. I thought it would be helpful for other companies that might need optical design and manufacturing to mention them.

Quoting GreenLights website:

“Greenlight Optics is an optical systems engineering and manufacturing company specializing in projection displays, LED and laser illumination, imaging systems, plastic optics, and the integration of optics with electrical and mechanical systems.”

Next Time – Display Devices and Test and Measurement Companies

In the next part of this series will on CES and AR/VR/MR 2023, I plan to cover display devices and a few test and measurement companies.

Mixed Reality at CES and the AR/VR/MR 2024 Video (Part 1 – Headset Companies)

✇KGOnTech
By: Karl Guttag
1 April 2024 at 15:29

Update 4/2/2024: Everysight corrected a comment I made about the size of their eyebox.

Introduction

This blog has covered mixed reality (MR) headsets, displays, and optics at CES since 2017 and SPIE’s AR/VR/MR conference since 2019. Both conferences occur in January each year. With this blog’s worldwide reputation (about half of the readers are from outside the U.S.), many companies want to meet. This year, I met with over 50 companies in just one month. Then Apple released the Apple Vision Pro on Feb. 2nd.

As this blog is a one-person operation, I can’t possibly write in detail about all the companies I have met with, yet I want to let people know about them. Last year, in addition to articles on some companies, Brad Lynch of the SadlyIsBradley YouTube channel and I made videos about many companies I met at CES 2023. Then, for AR/VR/MR 2023, I wrote an eight (8) part series of articles on AR/VR/MR. For CES 2024, I wrote a three (3) part series covering many companies.

However, with my Apple Vision Pro (AVP) coverage plus other commitments, I couldn’t see how to cover the over 50 companies I met with in January. While the AVP is such a major product in mixed reality and is important for a broad audience, I don’t want the other companies working on MR headsets, displays, and optics to be forgotten. So, I asked Jason McDowall of The AR Show to moderate a video presentation of the over 50 companies, with each company getting one slide.

Jason and I recorded for about 4 hours (before editing), split over two days, which works out to less than 5 minutes per company. This first hour of the video covers primarily headset companies. I made an exception for the combination of Avegant’s prototype that used Dispelix as it seemed to fit with the headsets.

In editing the video, I realized my presentation was a little “thin” regarding details on some companies. I’m adding some supplementary information and links to this article. I also moved a few companies around in the editing process and re-recorded a couple of sections, so the side numbers don’t always go in order.

Subscription Options Coming to KGOnTech

Between travel expenses and buying an Apple Vision Pro (AVP) with a MacBook for testing the AVP, I spent about $12,000 out of pocket in January and early February alone. Nobody has ever paid to be included (or excluded) in this blog. This blog, which started as a part-time hobby, has become expensive in terms of money and a full-time job. What makes it onto the blog is the tip of the iceberg of time spent on interviews, research, photographing and editing pictures and videos, and travel.

Many companies, including other news outlets and individuals, benefit from this blog indirectly through education or directly via the exposure it gives to large and small companies. Many, if not most, MR industry insiders read this blog worldwide based on my conference interactions. I want to keep the main blog free and not filled with advertising while still reporting on large and small companies. To make financial sense of all this and pay some people to help me, I’m in the process of setting up subscription services for companies and planning on (paid) webinars for individuals. If you or your company might be interested, please email subscriptions@kgontech.com.

Outline of the Video and Additional Information

Below is an outline of the first hour of the video, along with some additional comments and links to more information. The times in blue on the left of each subsection below are the times in the YouTube video discussing a given company.

0:00 Jason McDowall of the AR Show and Karl Guttag of KGOnTech introductions.

Jason and I briefly introduced ourselves.

2:59 Mixed Reality Major Design Challenges

My AR/MR design challenge list started with 11 items in a guest article in Display Daily in December 2015 with Sorry, but there is no Santa Claus – Display Daily. Since then, the list has grown to 23.

The key point is that improving any of these items will negatively affect multiple other items. For example, having a wider field of view (FOV) will make the optics bigger, heavier, and more expensive. It will also require a higher resolution display to support the same or better angular resolution, which, in turn, means more pixels requiring more processing, which will need more power, which means bigger batteries and more thermal management. All these factors combine to hurt cost and weight.

6:34 Xreal (Formerly Nreal)

I’ve followed Nreal (now Xreal) since its first big splash in the U.S. at CES 2019 (wow, five years ago). Xreal claims to have shipped 300,000 units last year, making it by far the largest unit volume shipper of optical AR headsets.

At CES 2024, Xreal demonstrated a future design that goes beyond their current headsets and adds cameras for image recognition and SLAM-type features.

BMW invited me to a demo of their proof-of-concept glasses-based heads-up display. The demo used Xreal glasses as the display device. BWM had added a head-tracking device under its rearview mirror to lock the user’s view of the car.

But even at CES 2019, Nreal was a case of déjà vu, as it looked so much like a cost-reduced version of the Osterhaut Design Group (ODG) R-9 that I first saw at CES 2017 and started covering and discussing in 2016. The ODG R-9 and the original X-Real had similar birdbath designs and used a Sony 1920×1080 Micro-OLED display. According to a friend of this blog and a former ODG R-9 designer and now CEO of the design firm PulsAR, David Bonelli, there are still some optical advantages of the ODG R-9 that others have yet to copy.

Below is a link to my recent article on CES, which discusses Xreal and my ride wearing the BMW AR demo. I have also included some links to my 2021 teardown of the Nreal birdbath optics and 2016 and 2017 articles about the ODG-R9.

11:48 Vuzix

Vuziz was founded in 1997 before making see-through AR devices, no less waveguides, became practical. It now has a wide range of products aimed at different applications. Vuzix founder and CEO Paul Travers has emphasized the need for rugged, all-day wearable AR glasses.

Vuzix historically has primarily had small, lightweight designs, with most later products having a glasses-like form factor. Vuzix originally licensed waveguide technology from Nokia, the same technology Microsoft licensed and later acquired for its Hololens 1. Vuzix says its current waveguide designs are very different from what it licensed from Nokia.

Vuzix’s current waveguide-based products include the monocular BLADE and the biocular SHIELD, which use Texas Instruments DLP displays.  Vuzix ‘s latest products are the Ultralight and Ultralight-S, which use Jade Bird Display MicroLEDs driving a waveguide. The current monocular designs use a green-only Jade Bird Display (JBD) with a 640 by 480 resolution and weigh only 34 grams. Vuzix has also announced plans to partner with the French startup Atomistic to develop full-color on a single device, MicroLEDs.

Multiple companies use Vuzix glasses as the headset platform to add other hardware and software layers to make application AR headsets. Xander was at CES with their AI voice-to-text glasses (discussed later). The company 3D2Cut has AI software that shows unskilled workers where to prune wine grape vines based on inputs from vine pruning experts. At last year’s CES, I met with 360world and their ThermalGlass prototype, which added thermal cameras to a Vuzix headset.

Below are links to my 2024 CES article that included Vuzix, plus a collection of other articles about Vuzix from prior years:

17:13 Digilens

I’ve met with Digilens many times through the years. This year was primarily an update and improvements on this major announcement of their Argo headset from last year (see 2023 article and video via the links below).

Digilens said that in response to my comments last year, they designed an Argo headband variant with a rigid headband that does not rest on the nose and can be flipped up out of view. This new design supports wearing ordinary glasses and is more comfortable for long-term wear. Digilens said many of their customers like this new design variation. A major problem I see with the Apple Vision Pro is the way it is uncomfortably clamped to the face and that it does not flip up like, say, the Lynx MR headset (see also video with Brad Lynch) and Sony MR Headset announced at CES 2024 (which looks very much like the Lynx headset).

Digilens also showed examples of their one-, two-, and three-layer waveguides, which can trade in weight and cost for differences in image quality. They also showed examples of moving the exit grating to different locations in the waveguide.

As I have covered Digilens so much in the past (see links below for some more recent articles), this year’s video was just an update:

20:00 Avegant

Avegant has become a technology development company. They are currently focused on designing small LCOS engines for AR glasses. They presented an update at the AR/VR/MR 2024 conference. Right before the conference, Avegant announced its development of “Spotlight™” to improve contrast by selective illumination of the LCOS panel, similar to LED array LCD TVs with local dimming.

Avengant has shown a very small 30-degree FOV, LCOS-based, 1280×720 pixel, light engine supporting a glasses-like form factor. Avegant’s glasses designs support higher resolution, larger FOV, and a smaller form factor than laser beam scanning or X-Cube-based MicroLEDs (see TCL below). They also got over 1 million nits out of their 30-degree FOV engines. While Avegant designed and built the projector engine and prototype glasses, they used Dispelix waveguides (to be discussed next).

Below are links to blog articles about Avegant’s small LCOS engines:

24:46 Dispelix (and Avegant)

Dispelix is a waveguide design company, not a headset maker. Avegant, among others, was using Dispelix waveguides (and why they were discussed at this point in the video).

Dispelix presented at the AR/VR/MR conference, where they discussed their roadmap to improve efficiency, reduce “eye glow,” and reduce “rainbow artifacts” caused by diffraction grating light capture.

Dispelix claims to have a roadmap to improve light throughput by a factor of ~4.5 over its current Selva design.

Dispelix, like several other diffractive waveguide companies, including Vuzix and Digilens, uses pantoscopic (front to back) tilt to reduce the eye glow effect, which is common with most other diffractive waveguides (most famously, Hololens). It turns out that for every one-degree of tilt, the “glow” is tilted down by two degrees such that with just a few degrees of tilt, the glow is projected well below most people’s view. Displelix has said that a combination of grating designs and optical coatings can nearly eliminate the glow in future designs.

Another problem (not discussed in the video) that has plagued diffractive waveguides has been the “rainbow artifact” caused by external light, particularly overhead from in front or behind the waveguide, being directed to the eye from the diffraction gratings. Because the gratings effect is wavelength-dependent, the light is broken into multiple colors (like a rainbow). Dispelix says they are developing designs that will direct the unwanted external light away from the eye.

(2024) CES (Pt. 2), Sony XR, DigiLens, Vuzix, Solos, EverySight, Mojie, TCL color µLED

30:50 Tilt-Five (and CEO Jeri Ellsworth)

I met with Jeri Ellsworth, the CEO of Tilt-Five, at CES. In addition to getting an update on Tilt-Five (with nothing I can’t talk about), Jeri and I discussed our various histories working on video game hardware, graphics co-processors, and augmented reality.

BTW, Jeri Ellsworth, Jason McDowall, Adi Robertson (editor at The Verge), Ed Tang (CEO of Avegant), and I are slated to be on a panel discussion at AWE 2024.

Below are some links to my prior reporting on Tilt-Five.

36:05 Sightful Spacetop

Sightful’s Spacetop is essentially a laptop-like keyboard and computer with Xreal-type birdbath optics using 1920×1080 OLED microdisplays with a 52-degree FOV. Under the keyboard are the processing system (Qualcomm Snapdragon XR2 Kryo 585TM 8-core 64-bit CPU and AdrenoTM 650 GP), memory (8GB), flash (128GB), and battery (5 hours of typical use). The system runs a “highly modified” Android operating system.

I saw Sightful at the Show Stoppers media event at CES, and they were nice enough to bring me custom prescription inserts to the AR/VR/MR conference. Sightful’s software environment supports multiple virtual- monitors/windows of various sizes, which are clipped to the glasses’ 1920×1080, 52-degree view. I believe the system uses the inertial sensors in the headset to make the virtual monitors appear stationary as opposed to the more advanced SLAM (simultaneous localization and mapping) used by many larger headsets.

As a side note, my first near-eye-display work in 1998 was on a monocular headset to be used with laptops as a private display when traveling. I designed the 1024×768 (high resolution for a 1998 microdisplay) LCOS display device and its controller. The monocular headset used color sequential LED illumination with birdbath mirror optics. Given the efficiency and brightness of LEDs of the day, it was all we could do to make a non-see-through monocular device. Unfortunately, the dot-com bust happened in 1999, which took out many high-tech startups.

I wrote about Sightful in my 2024 CES coverage:

36:05 Nimo

Nimo’s “Spatial Computing” approach is slightly different from Sightful’s. Instead of combining the computing hardware with the keyboard like Sightful, Nimo has a small computing and battery module that works as a 3-D spatial mouse with a trackpad (on top). Nimo has a USB-C connection for AR glasses, WiFi 6, and Bluetooth 5.1 for communication with an (optional) wireless keyboard.

The computing specs resemble Sightful’s, with a Qualcomm® XR2 8-core CPU, 8GB RAM, and 128GB Storage. Nimo supports working with Rokid, Xreal, and its own LetinAR-Optics-based 1920×1080 OLED AR glasses via its USB-C port, which provides display information and power.

Like Sightful, Nimo has a modified Android Operating system that supports multiple virtual monitors/windows. It uses the various glasses’ internal sensors to detect head movement to keep the monitors stationary in 3-D space as the user’s head moves.

I wrote about Nimo Planet in my 2024 CES coverage:

38:59 .Lumen (headset for the blind)

Lumen is a headset for blind people that incorporates lidar, cameras, and other sensors. Rather than outputting a display image, it provides haptic and audible feedback to the user. I don’t know how to judge this technology, but it seems like an interesting case where today’s technology could help people.

40:07 Ocutrx Oculenz

Ocutrx’s OcuLenz was initially aimed at helping people with macular degeneration and other forms of low vision. However, at the Ocutrx booth on its website at the CES ShowStoppers event, Ocutrx emphasized that the headset could be used for more than low vision, including gamers, surgeons, and military personnel. The optical design was done by an old friend, David Kessler, whom I ran into at the Ocutrx booth at CES and the AR/VR/MR conference.

The Oculenz uses larger-than-typical birdbath optics to support a 72-degree (diagonal) FOV. It uses 2560 x 1440 pixels per eye, so they will have a similar angular resolution but wider FOV than the more common 1920×1080 birdbath glasses (e.g., Xreal), which typically have 45- to ~50-degree FOVs. Unlike the typical birdbath glasses, which have separate processing, the Oculenz integrates a Qualcomm Snapdragon® XR2 processor, Wi-Fi, and cellular connectivity. This headset was originally aimed at people with low vision as a stand-alone device.

I wrote about Ocutrx and some of the issues of funding low-vision glasses in my earlier report on CES 2024, linked below:

44:22 Everysight

Everysight has AR glasses in a glasses-like form factor. They are designed to be self-contained, weigh only 47 grams, and have no external wiring. They use a 640×400 pixel full-color OLED display and can achieve >1000 nits to the eye.

Everysight uses a “Pre-Compensated Off-Axis” optical design, which tends to get more than double the light from the display to the eye while enabling more than three times the real-world light to pass through the display area compared to birdbath (e.g., Xreal) designs. With this design, the pre-compensation optics pre-correct for hitting the curved semi-mirror combiner off-axis. Typically, this mirror will be 50% or less reflective and only has to be applied over where the display is to be seen.

However, the Everysight glasses only support a rather small 22-degree FOV, and the eyebox is rather small. While Everysight has reduced the panoscopic tilt of the lenses over prior models, the latest Maverick modes still tilt toward the user’s cheeks more than most common glasses.

UPDATE 4/2/2024: Everysight responded to my original eyebox comment, “With respect to the eyebox, we take care of that with different sizes (Maverick today has two sizes – Medium and Large). The important part is that once you have the correct size, glass or eye movements won’t take you out of the eyebox. We believe that this is a much better tradeoff than a one-size-fits-all [with] low optical efficiency and enables you to use OLEDs in sunny days outdoors, even with clear visors.“

Thus far, Everysight seems to be marketing its glasses more to the sports market, which needs s, lightight headsets with bright displays for outdoor use.

If vision correction is not required, the lenses can be easily swapped out for various types of tint. More recently, Everysight has been able to support prescription lenses. For prescriptions, the inner curved mirror corrects for the virtual image, and a corrective lens on the outside corrects for the real world, including correcting for the curvature of the inner surface with the semi-mirror.

Everysight spun out of the large military company ELBIT, which perfected the pre-compensated off-axis design for larger headsets. This optical design is famously used in the F35 helmet and, more recently, in the civilian aircraft Skylens head-wearable HUD display, which has received FAA approval for use in multiple civilian aircraft, including recently the 737ng family.

Everysight was discussed in my CES 2024 coverage linked to below:

48:42 TCL RayNeo X2 and X2 Lite

At CES 2024, TCL showed their RayNex X2 and their newer X2 Light. I have worked with 3-chip LCOS projectors with an X-Cube in the past, and I was curious to see the image quality as I know from experience aligning to X-Cubes is non-trivial, particularly with the smaller sizes of the Jade Bird Display red, green, and blue MicroLED displays.

Overall, the newer X2 Lite using the Applied Materials (AMAT) waveguides looked much better than the earlier RayNeo X2 (non-Lite). Even the AMAT had significant front projection, but as discussed with respect to Displelix above, this problem can be managed, at least for smaller FOVs (the RayNeo X2s have a ~30-degree diagonal FOV).

I covered the TCL color µLED in more detail in my CES 2024 coverage (link below). I have also included links to articles discussing the Jade Bird Displays MicroLEDs and their use of an X-Cub for a color combiner:

55:54 Mojie/Meta Bounds

Mojie/Meta Bound showed 640×480 green-only MicroLED-based glasses claiming 3,000 nits (to the eye), 90% transparency (without tinting), a 28-degree FOV, and a weight of only 38 grams. These were also wireless and, to a first approximation, very similar to Vuzix UltraLite. One thing that makes them stand out is that they use a waveguide technology made of plastic resin (most use glass).

Many companies are experimenting with plastic waveguides to reduce weight and improve safety. So far, the color uniformity with full-color displays has been worse than with glass-based waveguides. However, the uniformity issues are less noticeable with a monochrome (green) display. Mitsui Chemicals and Mitsubishi Chemicals, both of Japan, are suppliers of resin plastic substrate material for waveguides.

Below is a link to my article on Mojie/Meta Bounds in my CES 2024 coverage:

57:59 Canon Mixed Reality

Canon had a fun demo based on the 100+ camera Free Viewpoint Video System VR system. Basically, you could sit around a table and see a basketball game (I think it was the 2022 NBA All-Stars Game) played on that table from any angle. Canon has been working on this technology for a decade or more, with demos for both basketball and soccer (football). While it’s an interesting technology demo, I don’t see how this would be a great way to watch a complete game. Even with over 100 cameras and the players being relatively small (far away virtually), one could see gaps where that the cameras couldn’t cover.

Canon also showed a very small passthrough AR camera and lens setup. While it was small, the FOV and video quality were not impressive. Brad Lynch of SadlyItsBradley found it to be pointless.

I have personally purchased a lot of Canon camera equipment over the last 25 years (including my Canon R5, which I take pictures with for this blog), so I am not in any way against Canon. However, as I discussed with Brad Lynch about Canon’s booth at CES 2023 (YouTube Link), I can’t see where Canon is going or what message they are trying to send in terms of mixed reality despite their very large and expensive booth. On the surface, Canon seems to be dabbling in various MR technologies, but it is not moving in a clear direction.

59:54 Solos (and Audio Glasses)

Solos makes audio-only glasses similar to the Meta/RayBand Wayfarer (but without cameras). These glasses emphasize modular construction, with all the expensive “smarts” in the temples so that the front-part lenses can be easily swapped.

Like several others, Solos uses cellular communication to connect to ChatGPT to do on-the-fly translations. What makes Solos more interesting is that Its Chairman is John Fan, also the chairman of Lightning Silicon Technology (a spinoff of Kopin Displays), a maker of OLED Microdisplays. At Lighting Silicon’s CES 2024 suite, John Fan discussed that incorporating the displays into the Solos glasses was an obvious future step.

CES (Pt. 2), Sony XR, DigiLens, Vuzix, Solos, EverySight, Mojie, TCL color µLED

1:01:16 Xander

While I saw Xander in the AARP sponsor AgeTech Summit booth at CES 2024, I didn’t get to meet with them. Xander hits at a couple of issues I feel are important. First, they show how AR technology can be used to help people. Secondly, they show what is expected to be a growing trend of adding basic visual information to augment audio.

While I (Karl) missed Xander at CES 2024, it turns out that Jason McDowall’s The AR Show (with guest host Kaden Pierce) recently interviewed Xander CEO Alex Westner on The AR Show.

Next Time – Optics and Display Devices

The video’s next part will discuss optical and display device companies.

CES (Pt. 2), Sony XR, DigiLens, Vuzix, Solos, Xander, EverySight, Mojie, TCL color µLED

✇KGOnTech
By: Karl Guttag
24 January 2024 at 15:24

Introduction

As I wrote last time, I met with nearly 40 companies at CES, of which 31 I can talk about. This time, I will go into more detail and share some photos. I picked the companies for this article because they seemed to link together. The Sony XR headset and how it fit on the user’s head was similar to the newer DigiLens Argo headband. DigiLens and the other companies had diffractive waveguides and emphasized lightweight and glass-like form factors.

I would like to caution readers of my saying that “all demos at conferences are magic shows,” something I warn about near the beginning of this blog in Cynics Guide to CES – Glossary of Terms). I generally no longer try to take “through the optics” pictures at CES. It is difficult to get good representative photos in the short time available with all the running around and without all the proper equipment. I made an exception for the TCL color MicroLED glasses as they readily came out better than expected. But at the same time, I was only using test images provided by TCL and not test patterns that I selected. Generally, the toughest test patterns (such as those on my Test Pattern Page) are simple. For example, if you put up a solid white image and see color in the white, you know something is wrong. When you put up colorful pictures with a lot of busy detail (like a colorful parrot in the TCL demo), it is hard to tell what, if anything, is wrong.

The SPIE AR/VR/MR 2024 in San Francisco is fast approaching. If you want to meet, contact me at meet@kgontech.com). I hope to get one or two more articles on CES before leaving for the AR/VR/MR conference.

Sony XR and DigiLens Headband Mixed Reality (with contrasts to Apple Vision Pro)

Sony XR (and others compared to Apple Vision Pro)

This blog expressed concerns about the Apple Vision Pro’s (AVP) poor mechanical ergonomics (AVP), completely blocking peripheral vision and the terrible placement of the passthrough cameras. My first reaction was that the AVP looked like it was designed by a beginner with too much money and an emphasis on style over functionality. What I consider Apple’s obvious mistakes seem to be addressed in the new Sony XR headset (SonyXR).

The SonyXR shows much better weight distribution, with (likely) the battery and processing moved to the back “bustle” of the headset and a rigid frame to transfer to the weight for balance. It has been well established that with designs such as the Hololens 2 and Meta Quest Pro, this type of design leads to better comfort. This design approach can also move a significant amount of power to the back for better heat management due to having a second surface radiating heat.

The bustle on the back design also avoids the terrible design decision by Apple to have a snag hazard and disconnection nuisance with an external battery and cable.

The SonyXR is shown to have enough eye relief to wear typical prescription glasses. This will be a major advantage in many potential XR/MR headset uses, making it more interchangeable. This is particularly important for use cases that are not all-day or one-time (ex., museum tours, and other special events). Supporting enough eye relief for glasses is more optically difficult and requires larger optics for the same field of view (FOV).

Another major benefit of the larger eye relief is that it allows for peripheral vision. Peripheral vision is considered to start at about 100 degrees or about where a typical VR headset’s FOV stops. While peripheral vision is low in resolution, it is sensitive to motion. It alerts the person to motion so they will turn their head. The saying goes that peripheral vision evolved to keep humans from being eaten by tigers. This translated to the modern world, being hit by moving machinery and running into things that might hurt you.

Another good feature shown in the Sony XR is the flip-up screen. There are so many times when you want to get the screen out of your way quickly. The first MR headset I used that supported this was the Hololens 2.

Another feature of the Hololens 2 is the front-to-back head strap (optional but included). Longtime VR gamer and YouTube personality Brad Lynch of the SadlyItsBradley YouTube channel has tried many VR-type headsets and optional headbands/straps. Brad says that front-to-back straps/pads generally provide the most comfort with extended use. Side-to-side straps, such as on the AVP, generally don’t provide the support where it is needed most. Brad has also said that while a forehead pad, such as on the Meta Quest Pro, helps, headset straps (which are not directly supported on the MQP) are still needed. It is not clear whether the Sony XR headset will have over-the-head straps. Even companies that support/include overhead straps generally don’t show them in the marketing photos and demos as they mess up people’s hair.

The SonyXR cameras are located closer to the user’s eyes. While there are no perfect placements for the two cameras, the further they are from the actual location of the eyes, the more distortion will be caused for making perspective/depth-correct passthrough (for more on this subject, see: Apple Vision Pro Part 6 – Passthrough Mixed Reality (PtMR) Problems).

Lynx R1

Lynx also used the headband with a forehead pad, with the back bustle and flip-up screen. Lynx also supports enough eye relief for glasses and good peripheral vision and locates their passthrough cameras near where the eye will be when in use. Unfortunately, I found a lot of problems with the optics Lynx chose for the R1 by the optics design firm Limbak (see also my Lynx R1 discussion with Brad Lynch). Apple has since bought Limbak, and it is likely Lynx will be moving on with other optical designs.

Digilens Argo New Head Band Version at CES 2024

I wrote a lot about Digilens Argo in last year’s coverage of CES and the AR/VR/MR conference in DigiLens, Lumus, Vuzix, Oppo, & Avegant Optical AR (CES & AR/VR/MR 2023 Pt. 8). In the section Skull-Gripping “Glasses” vs. Headband or Open Helmet, I discussed how Digilens has missed an opportunity for both comfort and supporting the wearing of glasses. Digilens said they took my comments to heart and developed a variation with the rigid headband and flip-up display shown in their suite at CES 2024. Digilens said that this version let them expand their market (and no, I didn’t get a penny for my input).

The Argos are light enough that they probably don’t need an over-the-head band for extra support. If the headband were a ground-up design rather than a modular variation, I would have liked to see the battery and processing moved to a back bustle.

While on the subject of Digilens, they also had a couple of nice static displays. Pictured below right are variations in waveguide thickness they support. Generally, image quality and field of view can be improved by supporting more waveguide layers (with three layers supporting individual red, green, and blue waveguides). Digilens also had a static display using polarized light to show different configurations they can support for the entrance, expansion, and exit gratings (below right).

Vuzix

Vuzix has been making wearable heads-up displays for about 26 years and has a wide variety of headsets for different applications. Vuzix has been discussed on this blog many times. Vuzix primarily focuses on lightweight and small form factor glasses and attachments with displays.

Vuzix Ultralite Sport (S) and Forward Projection (Eye Glow) Elimination

New this year at CES was Vuzix’s Ultralite Sports (S) model. In addition to being more “sporty” looking, their waveguides are designed to eliminate forward projection (commonly referred to as “Eye Glow”). Eye glow was famously an issue with most diffractive waveguides, including the Hololens 1 & 2 (see right), Magic Leap 1 & 2, and previous Vuzix waveguide-based glasses.

Vuzix appears to be using the same method that both Digilens and Dispelix discussed in their AR/VR/MR 2022 papers that I discussed with Brad Lynch in a YouTube video after AR/VR/MR 2022 and in my blog article, DigiLens, Lumus, Vuzix, Oppo, & Avegant Optical AR (CES & AR/VR/MR 2023 Pt. 8) in the sections on Eye Glow.

If the lenses are canted (tilted), the exit gratings, when designed to project to the eye, will then project down at twice the angle at which the waveguides are canted. Thus, with only a small change in the tilt of the waveguides, the projection will be far below the eyesight of others (unless they are on the ground).

Ultra Light Displays with Audio (Vuzix/Xander) & Solos

Last year, Vuzix introduced their lightweight (38 grams) Z100 Ultralite, which uses 640×480 green (only) MicroLED microdisplays. Xander, using the lightweight Vuzix’s Z100, has developed text-to-speech glasses for people with hearing difficulties (Xander was in the AARP booth at CES).

While a green-only display with low resolution by today’s standards is not something you will want to watch movies, there are many uses for having a limited amount of text and graphics in a lightweight and small form factor. For example, I got to try out Solos Audio glasses, which, among other things, use ChatGPT to do on-the-fly language translation. It’s not hard to imagine that a small display could help clarify what is being said about Solos and similar products, including the Amazon Echo Frames and the Ray-Ban Meta Wayfarer.

Mojie (Green) MicroLED with Plastic Waveguide

Like Vuzix Z100, the Mojie (a trademark of Meta-Bounds) uses green-only Jade Bird Display 640×480 microLEDs with waveguide optics. The big difference is that Mojie, along with Oppo Air 2 and Meizu MYVU, all use Meta-Bounds resin plastic waveguides. Unfortunately, I didn’t get to the Mojie booth until near closing time at CES, but they were nice enough to give me a short demo. Overall, regarding weight and size, the Mojie AR glasses are similar to the Vuzix Z100, but I didn’t have the time and demo content to judge the image quality. Generally, resin plastic diffractive waveguides to date have had lower image quality than ones on a glass substrate.

I have no idea what resin plastic Meta-Bounds uses or if they have their own formula. Mitsui Chemicals and Mitsubishi Chemicals, both of Japan, are known to be suppliers of resin plastic substrate material.

EverySight

ELBIT F35 Helmet and Skylens

Everysight (the company, not the front eye display feature on the Apple Vision Pro) has been making lightweight glasses primarily for sports since about 2018. Everysight spun out of the major defense (including the F35 helmet HUD) and commercial products company ELBIT. Recently, ELBIT had their AR glasses HUD approved by the FAA for use in the Boeing 737ng series. EverySight uses an optics technology, which I call “precompensated off-axis.” Everysight (and ELBIT) have an optics engine that projects onto a curved front lens with a partial mirror coating. The precompensation optics of the projector correct for the distortion from hitting a curved mirror off-axis.

The Everysight/Elbit technology is much more optically efficient than waveguide technologies and more transparent than “birdbath technologies” (the best-known birdbath technology today being Xreal). The amount of light from the display versus transparency is a function of the semi-transparent mirror coating. The downside of the Eversight optical system with small-form glasses is that the FOV and Eyebox tend to be smaller. The new Everysight Maverick glasses have a 22-degree FOV and produce over 1,000 nits using a 5,000 nit 640×400 pixel full-color Sony Micro-OLED.

The front lens/mirror elements are inexpensive and interchangeable. But the most technically interesting thing is that Everysight has figured out how to support prescriptions built into the front lens. They use a “push-pull” optics arrangement similar to some waveguide headsets (most notably Hololens 1&2 and Magic Leap). The optical surface on the eye side of the lens corrects for the virtual display of the eye, and the optical surface on the outside surface of the lens is curved to do what is necessary to correct vision correction for the real world.

TCL RayNeo X2 and Ray Neo X2 Lite

I generally no longer try to take “through the optics” pictures at CES. It is very difficult to get good representative photos in the short time available with all the running around and without all the proper equipment. I got some good photos through TCL’s RayNeo X2 and the RayNeo X2 Lite. While the two products sound very close, the image quality with the “Lite” version, which switched to using Applied Materials (AMAT) diffractive waveguides, was dramatically better.

The older RayNeo X2s were available to see on the floor and had problems, particularly with the diffraction gratings capturing stray light and the general color quality. I was given a private showing of the newly announced “Lite” version using the AMAT waveguides, and not only were they lighter, but the image quality was much better. The picture on the right below shows the RayNeo X2 (with an unknown waveguide) on the left that captures the stray overhead light (see streaks at the arrows). The picture via the Lite model (with the AMAT waveguide) does not exhibit these streaks, even though the lighting is similar. Although hard to see in the pictures, the color uniformity with the AMAT waveguide also seems better (although not perfect, as discussed later).

Both RayNeo models use 3-separate Jade Bird Display red, green, and blue MicroLEDs (inorganic) with an X-cube color combiner. X-cubes have long been used in larger LCD and LCOS 3-panel projectors and are formed with four prisms with different dichroic coatings that are glued together. Jade Bird Display has been demoing this type of color combiner since at least AR/VR/MR 2022 (above). Having worked with 3-Panel LCOS projectors in my early days at Syndiant, I know the difficulties in aligning three panels to an X-cube combiner. This alignment is particularly difficult with the size of these MicroLED displays and their small pixels.

I must say that the image quality of the TCL RayNeo X2 Lite exceeded my expectations. Everything seems well aligned in the close-up crop from the same parrot picture (below). Also, there seems to be relatively good color without the wide variation from pixel-to-pixel brightness I have seen in past MicroLED displays. While this is quite an achievement for a MicroLED system, the RayNeo X2 light only has a modest 640×480 resolution display with a 30-degree diagonal FOV. These specs result in about 26 pixels per degree or about half the angular resolution of many other headsets. The picture below was taken with a Canon R5 with a 16mm lens, which, as it turns out, has a resolving power close to good human vision.

Per my warning in the introduction, all demos are magic shows. I don’t know how representative this prototype will be of units in production, and perhaps most importantly, I did not try my test patterns but used the images provided by TCL.

Below is another picture of the parrot taken against a darker background. Looking at the wooden limb under the parrot, you will see it is somewhat reddish on the left and greenish on the right. This might indicate color shifting due to the waveguide, as is common with diffractive waveguides. Once again, taking quick pictures at shows (all these were handheld) and without controlling the source content, it is hard to know. This is why I would like to acquire units for extended evaluations.

The next two pictures, taken against a dark background and a dimly lit room, show what I think should be a white text block on the top. But the text seems to change from a reddish tint on the left to a blueish tint on the right. Once again, this suggests some color shifting across the diffractive waveguide.

Below is the same projected image taken with identical camera settings but with different background lighting.

Below is the same projected flower image with the same camera settings and different lighting.

Another thing I noticed with the Lite/AMAT waveguides is significant front projection/eye glow. I suspect this will be addressed in the future, as has been demonstrated by Digilens, Displelix, and Vuzix, as discussed earlier.

Conclusions

The Sony XR headset seems to showcase many of the beginner mistakes made by Apple with the AVP. In the case of the Digilens Argo last year, they seemed to be caught between being a full-featured headset and the glasses form factor. The new Argo headband seems like a good industrial form factor that allows people to wear normal glasses and flip the display out of the way when desired.

Vuzix, with its newer Ultralite Z100 and Sports model, seems to be emphasizing lightweight functionality. Vuzix and the other waveguide AR glasses have not given a clear path as to how they will support people who need prescription glasses. The most obvious approach they will do some form of “push-pull” with a lens before and after the waveguides. Luxexcel had a way to 3-D print prescription push-pull lenses, but Meta bought them. Add Optics (formed by former Luxexcel employees) has another approach with 3-D printed molds. Everysight tries to address prescription lenses with a somewhat different push-pull approach that their optical design necessitates.

While not perfect, the TCL color MicroLED, at least in the newer “Lite” version, was much better than I expected. At the same time, one has to recognize the resolution, FOV, and color uniformity are still not up to some other technologies. In other words, to appreciate it, one has to recognize the technical difficulty. I also want to note that Vuzix has said that they are also planning on color MicroLED glasses with three microdisplays, but it is not clear whether they will use an X-cube or a waveguide combiner approach.

The moderate success of smart audio glasses may be pointing the way for these ultra-light glasses form factor designs for a consumer AR product. One can readily see where adding some basic text and graphics would be of further benefit. We will know if this category has become successful if Apple enters this market 😁.

❌
❌