Archive for LCOS

CES 2017 AR, What Problem Are They Trying To Solve?

Introduction

First off, this post is a few weeks late. I got sick on returning from CES and then got busy with some other pressing activities.

At left is a picture that caught me next to the Lumus Maximus demo at CES from Imagineality’s “CES 2017: Top 6 AR Tech Innovations“. Unfortunately they missed that in the Lumus booth at about the same time was a person from Magic Leap and Microsoft’s Hololens (it turned out we all knew each other from prior associations).

Among Imagineality’s top 6 “AR Innovations” were ODG’s R-8/R-9 Glasses (#1) and Lumus’s Maximus 55 degree FOV waveguide (#3). From what I heard at CES and saw in the writeups, ODG and Lumus did garner a lot of attention. But by necessity, theses type of lists are pretty shallow in their evaluations and I try to do on this blog is go a bit deeper into the technology and how it applies to the market.

Among the near eye display companies I looked at during CES include Lumus, ODG, Vuzix, Real Wear, Kopin, Wave Optics, Syndiant, Cremotech, QD Laser, Blaze (division of eMagin) plus several companies I met with privately. As interesting to me as their technologies was there different takes on the market.

For this article, I am mostly going to focus on the Industrial / Enterprise market. This is were most of the AR products are shipping today. In future articles, I plan to go into other markets and more of a deep dive on the the technology.

What Is the Problem They Are Trying to Solve?

I have had an number of people asked me what was the best or most interesting AR thing I saw at CES 2017, and I realized that this was at best an incomplete question. You first need to ask, “What problem are they trying to solve?” Which leads to “how well does it solve that problem?” and “how big is that market?

One big takeaway I had at CES having talked to a number of different company’s is that the various headset designs were, intentionally or not, often aimed at very different applications and use cases. Its pretty hard to compare a headset that almost totally blocks a user’s forward view but with a high resolution display to one that is a lightweight information device that is highly see-through but with a low resolution image.

Key Characteristics

AR means a lot of different things to different people. In talking to a number of companies, you found they were worried about different issues. Broadly you can separate into two classes:

  1. Mixed Reality – ex. Hololens
  2. Informational / “Data Snacking”- ex. Google Glass

For most of the companies were focused on industrial / enterprise / business uses at least for the near future and in this market the issues include:

  1. Cost
  2. Resolution/Contrast/Image Quality
  3. Weight/Comfort
  4. See-through and/or look over
  5. Peripheral vision blocking
  6. Field of view (small)
  7. Battery life per charge

For all the talk about mixed reality (ala Hololens and Magic Leap), most of the companies selling product today are focused on helping people “do a job.” This is where they see the biggest market for AR today. It will be “boring” to the people wanting the “world of the future” mixed reality being promised by Hololens and Magic Leap.

You have to step back and look at the market these companies are trying to serve. There are people working on a factory floor or maybe driving a truck where it would be dangerous to obscure a person’s vision of the real world. They want 85% or more transparency, very lightweight and highly comfortable so it can be worn for 8 hours straight, and almost no blocking of peripheral vision. If they want to fan out to a large market, they have to be cost effective which generally means they have to cost less than $1,000.

To meet the market requirements, they sacrifice field of view and image quality. In fact, they often want a narrow FOV so it does not interfere with the user’s normal vision. They are not trying to watch movies or play video games, they are trying to give necessary information for person doing a job than then get out of the way.

Looking In Different Places For the Information

I am often a hard audience. I’m not interested in the marketing spiel, I’m looking for what is the target market/application and what are the facts and figure and how is it being done. I wanting to measure things when the demos in the boths are all about trying to dazzle the audience.

As a case in point, let’s take ODG’s R-9 headset, most people were impressed with the image quality from ODG’s optics with a 1080p OLED display, which was reasonably good (they still had some serious image problems caused by their optics that I will get into in future articles).

But what struck me was how dark the see-through/real world was when viewed in the demos. From what I could calculate, they are blocking about 95% of the real world light in the demos. They also are too heavy and block too much of a person’s vision compared to other products; in short they are at best going after a totally different market.

Industrial Market

Vuzix is representative of the companies focused on industrial / enterprise applications. They are using with waveguides with about 87% transparency (although they often tint it or uses photochromic light sensitive tinting). Also the locate the image toward the outside of the use’s view so that even when an image it displayed (note in the image below-right that the exit port of the waveguide is on the outside and not in the center as it would be on say a Hololens).

The images at right were captured from a Robert Scoble interview with Paul Travers, CEO of Vuzix. BTW, the first ten minutes of the video are relatively interesting on how Vuzix waveguides work but after that there is a bunch of what I consider silly future talk and flights of fancy that I would take issue with. This video shows the “raw waveguides” and how they work.

Another approach to this category is Realwear. They have a “look-over” display that is not see through but their whole design is make to not block the rest of the users forward vision. The display is on a hinge so it can be totally swung out of the way when not in use.

Conclusion

What drew the attention of most of the media coverage of AR at CES was how “sexy” the technology was and this usually meant FOV, resolution, and image quality. But the companies that were actually selling products were more focused on their user’s needs which often don’t line up with what gets the most press and awards.

 

ODG R-8 and R-9 Optic with a OLED Microdisplays (Likely Sony’s)

ODG Announces R-8 and R-9 OLED Microdisplay Headsets at CES

It was not exactly a secret, but Osterhout Design Group (ODG) formally announce their new R-8 headset with dual 720p displays (one per eye) and R-9 headset with dual 1080p displays.  According to their news release, “R-9 will be priced around $1,799 with initial shipping targeted 2Q17, while R-8 will be less than $1,000 with developer units shipping 2H17.

Both devices use use OLED microdisplays but with different resolutions (the R-9 has twice the pixels). The R-8 has a 40 degree field of view (FOV) which is similar to Microsoft’s Hololens and the R-9 has about a 50 degree FOV.

The R-8 appears to be marketed more toward “consumer” uses with is lower price point and lack of an expansion port, while ODG is targeting the R-9 to more industrial uses with modular expansion. Among the expansion that ODG has discussed are various cameras and better real world tracking modules.

ODG R-7 Beam Splitter Kicks Image Toward Eye

With the announcement comes much better pictures of the headsets and I immediately noticed that their optics were significantly different than I previously thought. Most importantly, I noticed in the an ODG R-8 picture that the beam splitter is angled to kicks the light away from the eye whereas the prior ODG R-7 had a simple beam splitter that kicks the image toward the eye (see below).

ODG R-8 and R-8 Beam Splitter Kicks Image Away From Eye and Into A Curved Mirror

The ODG R-8 (and R-9 but it is harder to see on the available R-9 pictures) does not have a simple beam splitter but rather a beam splitter and curve mirror combination. The side view below (with my overlays of the outline of the optics including some that are not visible) that the beam splitter kicks the light away from the eye and toward partial curved mirror that acts as a “combiner.” This curve mirror will magnify and move the virtual focus point and then reflects the light back through the beam splitter to the eye.

On the left I have taken Figure 169 from ODG’s US Patent 9,494,800. Light from the “emissive display” (ala OLED) passes through two lenses before being reflected into the partial mirror. The combination of the lenses and the mirror act to adjust the size and virtual focus point of the displayed image. In the picture of the ODG R-8 above I have taken the optics from Figure 169 and overlaid them (in red).

According to the patent specification, this configuration “form(s) at wide field of view” while “The optics are folded to make the optics assembly more compact.”

At left I have cropped the image and removed the overlay so you can see the details of the beam splitter and curved mirror joint.  You hopefully can see the seam where the beam splitter appears to be glued to the curved mirror suggesting the interior between the curved mirror and beam splitter is hollow. Additionally there is a protective cover/light shade over the outside of the curved mirror with a small gap between them.

The combined splitter/mirror is hollow to save weight and cost. It is glued together to keep dust out.

ODG R-6 Used A Similar Splitter/Mirror

I could not find a picture of the R-8 or R-9 from the inside, but I did find a picture on the “hey Holo” blog that shows the inside of the R-6 that appears to use the same optical configuration as the R-8/R-9. The R-6 introduced in 2014 had dual 720p displays (one per eye) and was priced at $4,946 or about 5X the price of the R-8 with the same resolution and similar optical design.  Quite a price drop in just 2 years.

ODG R-6, R-8, and R-9 Likely Use Sony OLED Microdisplays

Interestingly, I could not find anywhere were ODG says what display technology they use in the 2014 R-6, but the most likely device is the Sony ECX332A 720p OLED microdisplay that Sony introduced in 2011. Following this trend it is likely that the ODG R-9 uses the newer Sony ECX335 1080p OLED microdisplay and the R-9 uses the ECE332 or a follow-on version. I don’t know any other company that has both a 720p and 1080p OLED microdisplays and the timing of the Sony and ODG products seems to fit. It is also very convenient for ODG that both panels are the same size and could use the same or very similar optics.

Sony had a 9.6 micron pixel on a 1024 by 768 OLED microdisplay back in 2011 so for Sony the pixel pitch has gone from 9.6 in 2011 to 8.2 microns on the 1080p device. This is among the smallest OLED microdisplay pixel pitches I have seen but still is more than 2x linearly and 4x in area bigger than the smallest LCOS (several companies have LCOS pixels pitches in the 4 micron or less range).

It appears that ODG used an OLED microdisplay for the R-6 then switched (likely for cost reasons) to LCOS and a simple beam splitter for the R7 and then back to OLEDs and the splitter/mirror optics for the R-8 and R-9.

Splitter/Combiner Is an Old Optic Trick

This “trick” of mixing lenses with a spherical combiner partial mirror is an old idea/trick. It often turns out that mixing refractive (lenses) with mirror optics can lead to a more compact and less expensive design.

I have seen a beam splitter/mirror used many times. The ODG design is a little different in that the beam splitter is sealed/mated to the curved mirror which with the pictures available earlier make it hard to see. Likely as not this has been done before too.

This configuration of beam splitter and curve mirror even showed up in Magic Leap applications such as Fig. 9 from 2015/0346495 shown at right. I think this is the optical configuration that Magic Leap used with some of their prototypes including the one seen by “The Information.

Conclusion/Trends – Turning the Crank

The ODG optical design while it may seem a bit more complex than a simple beam splitter, is actually probably simpler/easier to make than doing everything with lenses before the beam splitter. Likely they went to this technique to support a wider FOV.

Based on my experience, I would expect that ODG optical design will be cleaner/better than the waveguide designs of Microsoft’s Hololens. The use of OLED microdisplays should give ODG superior contrast which will further improve the perceived sharpness of the image. While not as apparent to the casual observer, but as I have discussed previously, OLEDs won’t work with diffractive/holographic waveguides such as Hololens and Magic Leap are using.

What is also interesting that in terms of resolution and basic optics, the R-8 with 720p is about 1/5th the price of the military/industrial grade 720p R-6 of about 2 years ago. While the R-9 in addition to having a 1080p display, has some modular expansion capability, one would expect there will be follow-on product with 1080p with a larger FOV and more sensors in a price range of the R-8 in the not too distant future and perhaps with integration of the features from one or more of the R-9’s add-on modules; this as we say in the electronics industry, “is just a matter of turning the crank.”

Everything VR & AR Podcast Interview with Karl Guttag About Magic Leap

With all the buzz surrounding Magic Leap and this blog’s technical findings about Magic Leap, I was asked to do an interview by the “Everything VR & AR Podcast” hosted by Kevin Harvell. The podcast is available on iTunes and by direct link to the interview here.

The interview starts with about 25 minutes of my background starting with my early days at Texas Instruments. So if you just want to hear about Magic Leap and AR you might want to skip ahead a bit. In the second part of the interview (about 40 minutes) we get into discussing how I went about figuring out what Magic Leap was doing. This includes discussing how the changes in the U.S. patent system signed into law in 2011 with the America Invents Act help make the information available for me to study.

There should be no great surprises for anyone that has followed this blog. It puts in words and summarizes a lot that I have written about in the last 2 months.

Update: I listen to the podcast and noticed that I misspoke a few times; it happens in live interviews.  An unfathomable mistake is that I talked about graduating college in 1972 but that was high school; I graduated from Bradley University with a B.S. in Electrical Engineering in 1976 and then received and MSEE from The University of Michigan in 1977 (and joined TI in 1977).  

I also think I greatly oversimplified the contribution of Mark Harward as a co-founder at Syndiant. Mark did much more than just have desigeners, he was the CEO, an investor, and and the company while I “played” with the technology, but I think Mark’s best skill was in hiring great people. Also, Josh Lund, Tupper Patnode, and Craig Waller were co-founders. 

 

Kopin Entering OLED Microdisplay Market

Kopin Making OLED Microdisplays

Kopin announced today that they are getting into the OLED Microdisplay business. This is particularly notable because Kopin has been a long time (since 1999) manufacture of transmissive LCD microdisplays used in camera viewfinders and near eye display devices. They also bought Forth Dimension Displays back in 2011, a maker of high resolution ferroelectric reflective LCOS used in higher end near eye products.

OLED Microdisplays Trending in AR/VR Market

With the rare exception of the large and bulky Meta 2, microdisplays, (LCOS, DLP, OLED, and transmissive LCD), dominate the AR/MR see-through market. They also are a significant factor in VR and other non-see-through near eye displays

Kopins entry seems to be part of what may be a trend toward OLED Microdisplays used in near eye products. ODG’s next generation “Horizon” AR glasses is switching from LCOS (used in the current R7) to OLED microdisplays. Epson which was a direct competitor to Kopin in transmissive LCD, switched to OLED microdisplays in their new Moverio BT-300 AR glasses announced back in February.

OLED Microdisplays Could Make VR and Non-See-Through Headsets Smaller/Lighter

Today most of the VR headsets are following Oculus’s use of large flat panels with simple optics. This leads to large bulky headsets, but the cost of OLED and LCD flat panels is so low compared to other microdisplays with their optics that they win out. OLED microdisplays have been far too expensive to compete on price with the larger flat panels, but this could change as there are more entrants into the OLED microdisplay market.

OLEDs Don’t Work With Waveguides As Used By Hololens and Magic Leap

It should be noted that the broad spectrum and diffuse light emitted by OLED is generally incompatible with the flat waveguide optics such as used by Hololens and is expected from Magic Leap (ML). So don’t expect to see these being used by Hololens and ML anytime soon unless they radically redesign their optics. Illuminated microdisplays like DLP and LCOS can be illuminated by narrower spectrum light sources such as LED and even lasers and the light can be highly collimated by the illumination optics.

Transmissive LCD Microdisplays Can’t Compete As Resolution Increases

If anything, this announcement from Kopin is the last nail in the coffin of the transmissive LCD microdisplay in the future. OLED Microdisplays have the advantages over transmissive Micro-LCD in the ability to go to higher resolution and smaller pixels to keep the overall display size down for a given resolution when compared to transmissive LCD. OLEDs consume less power for the same brightness than transmissive LCD. OLED also have much better contrast. As resolution increases transmissive LCDs cannot compete.

OLEDs Microdisplays More Of A Mixed Set of Pros and Cons Compared to LCOS and DLP.

There is a mix of pro’s and con’s when comparing OLED microdisplays with LCOS and DLP. The Pro’s for OLED over LCOS and DLP include:

  1. Significantly simpler optical path (illumination path not in the way). Enables optical solutions not possible with reflective microdisplays
  2. Lower power for a given brightness
  3. Separate RGB subpixels so there is no field sequential color breakup
  4. Higher contrast.

The advantages for LCOS and DLP reflective technologies over OLED microdisplays include:

  1. Smaller pixel equals a smaller display for a given resoluion. DLP and LCOS pixels are typically from 2 to 10 times smaller in area per pixel.
  2. Ability to use narrow band light sources which enable the use of waveguides (flat optical combiners).
  3. Higher brightness
  4. Longer lifetime
  5. Lower cost even including the extra optics and illumination

Up until recently, the cost of OLED microdisplays were so high that only defense contractors and other applications that could afford the high cost could consider them. But that seems to be changing. Also historically the brightness and lifetimes of OLED microdisplays were limited. But companies are making progress.

OLED Microdisplay Competition

Kopin is long from being the first and certainly is not the biggest entry in the OLED microdisplay market. But Kopin does have a history of selling volume into the microdisplay market. The list of known competitors includes:

  1. Sony appears to be the biggest player. They have been building OLED microdisplays for many years for use in camera viewfinders. They are starting to bring higher resolution products to the market and bring the costs down.
  2. eMagin is a 23-year-old “startup”. They have a lot of base technology and are a “pure play” stock wise. But they have failed to break through and are in danger of being outrun by big companies
  3. MicoOLED – Small France startup – not sure where they really stand.
  4. Samsung – nothing announced but they have all the technology necessary to make them. Update: Ron Mertens of OLED-Info.com informed me that I was rumored that the second generation of Google Glass was considering a Samsung OLED microdisplay and that Samsung had presented a paper going back to 2011.
  5.  LG – nothing announced but they have all the technology necessary to make them.

I included Samsung and LG above not because I have seen or heard of them working on them, but I would be amazed if they didn’t at least have a significant R&D effort given their sets of expertise and their extreme interest in this market.

For More Information:

For more complete information on the OLED microdisplay market, you might want go to OLED-info that has been following both large flat panel and small OLED microdisplay devices for many years. They also have two reports available, OLED Microdisplays Market Report and OLED for VR and AR Market Report.

For those who want to know more about Kopin’s manufacturing plan, Chris Chinnock of Insight Media has an interesting article outlining Kopin’s fabless development strategy.

Magic Leap: Focus Planes (Too) Are a Dead End

What Magic Leap Appears to be Doing

For this article I would like to dive down on the most likely display and optics Magic Leap (ML) is developing for their their Product Equivalent (PEQ). The PEQ was discussed in the “The Information” story “The Reality Behind Magic Leap.” As I explained in my  November 20, 2016 article Separating Magic and Reality (before the Dec 8th “The Information” story) the ML patent application US 2016/0327789 best fits the available evidence and if anything the “The Information” article reinforce that conclusion. Recapping the evidence:

  1. ML uses a “spatial light modulator” as stated in “The Information”
  2. Most likely an LCOS spatial light modulator and the Oct. 27th 2017 Inside Business citing “KGI Securities analyst Ming-Chi Kuo, who has a reputation for being tapped into the Asian consumer electronics supply chain” claims ML is using a Himax LCOS device.
  3. Focus planes to support vergence/accommodation per many ML presentations and their patent applications
  4. Uses waveguides which fit the description and pictures of what ML calls a “Photonics Chip”
  5. Does not have a separate focus mechanism as reported in the “The Information” article.
  6. Could fit the form factor as suggested in “The Information”
  7. Its the only patent that shows serious optical design that also uses what could be considered a “Photonics chip.”

I can’t say with certainty that the optical path is that of application 2016/0327789. It is just the only optical path in the ML patent applications that fits all the available evidence and and has a chance of working.

Field of View (FOV)

Rony Abovitz, ML CEO, is claiming a larger a larger FOV.  I would think ML would not want to be have lower angular resolution than Hololens. Keeping the same 1.7 arc minutes per pixel angular resolution as Hololens and ODG’s Horizon, this would give a horizontal FOV of about 54.4 degrees.

Note, there are rumors that Hololens is going to be moving to a 1080p device next year so ML may still not have an advantage by the time they actually have a product. There is a chance that ML will just use a 720p device, at least at first, and accept lower angular resolution of say 2.5 or greater to get into the 54+ FOV range. Supporting a larger FOV is not small trick with waveguides and is  one thing that ML might have over Hololoens; but then again Hololens is not standing still.

Sequential Focus Planes Domino Effect

The support of vergence/accommodation appears to be a paramount issue with ML. Light fields are woefully impractical for any reasonable resolution, so ML in their patent application and some of their demo videos show the concept of “focus planes.” But for every focus plane an image has to be generated and displayed.

The cost of having more than one display per eye including the optics to combine the multiple displays would be both very costly and physically large. So the only rational way ML could support focus planes is to use a single display device and sequentially display the focus planes. But as I will outline below, using sequential focus planes to address vergence/accommodation, comes at the cost of hurting other visual comfort issues.

Expect Field Sequential Color Breakup If Magic Leap Supports “Focus Planes”

Both high resolution LCOS and DLP displays use “field sequential color” where they have a single set of mirrors that display a single color plane at a time. To get the colors to fuse together in the eye they repeat the same colors multiple times per frame of an image. Where I have serious problems with ML using Himax LCOS is that instead of repeating colors to reduce the color breakup, they will be instead be showing different images to support Sequential Focus Planes. Even if they have just two focus planes as suggested in “The Information,” it means they will reduce the rate repeating of colors to help them fuse in the eye is cut in half.

The Hololens which also uses a field sequential color LCOS one can already detect breakup. Cutting the color update rate by 2 or more will make this problem significantly worse.

Another interesting factor is that field sequential color breakup tends to be more noticeable by people’s peripheral vision which is more motion/change sensitive. This means the problem will tend to get worse as the FOV increases.

I have worked many years with field sequential display devices, specifically LCOS. Based on this experience I expect that the human vision system  will do a poor job of “fusing” the colors at such slow color field update rates and I would expect people will see a lot of field sequential color breakup particularly when objects move.

In short, I expect a lot of color breakup to be noticeable if ML support focus planes with a field sequential color device (LCOS or DLP).

Focus Planes Hurt Latency/Lag and Will Cause Double Images

An important factor in human comfort is the latency/lag between any head movement and the display reacting can cause user discomfort. A web search will turn up thousands of references about this problem.

To support focus planes ML must use a display fast enough to support at least 120 frame per second. But to support just two focus planes it will take them 1/60th of a second to sequentially display both focus planes. Thus they have increase the total latency/lag from the time they sense movement until the display is updated by ~8.333 milliseconds and this is on top of any other processing latency. So really focus planes is trading off one discomfort issue, vergence/accommodation, for another, latency/lag.

Another issue which concerns me is how well sequential focus planes are doing to fuse in the eye. With fast movement the eye/brain visual system is takes its own asynchronous “snapshots” and tries to assemble the information and line it up. But as with field sequential color, it can put together time sequential information wrong, particularly if some objects in the image move and others don’t. The result will be double images, getting double images with sequential focus planes would be unavoidable with fast movement either in the virtual world or when a person moves their eyes. These problems will be compounded by color field sequential breakup.

Focus Planes Are a Dead End – Might Magic Leap Have Given Up On Them?

I don’t know all the behind the scenes issues with what ML told investors and maybe ML has been hemmed in by their own words and demos to investors. But as an engineer with most of my 37 years in the industry working with image generation and display, it looks to me that focus planes causes bigger problems than it solves.

What gets me is that they should have figured out that focus planes were hopeless in the first few months (much less if someone that knew what they were doing was there). Maybe they were ego driven and/or they built to much around the impression they made with their “Beast” demo system (big system using DLPs). Then maybe they hand waved away the problems sequential focus planes cause thinking they could fix them somehow or hoped that people won’t notice the problems. It would certainly not be the first time that a company committed to a direction and then felt that is had gone to far to change course. Then there is always the hope that “dumb consumers” won’t see the problems (in this case I think they will).

It is clear to me that like Fiber Scan Displays (FSD), focus planes are a dead end, period, full-stop. Vergence/accommodation is a real issue but only for objects that get reasonably close to the users. I think a much more rational way to address the issue is to use sensors to track the eyes/pupils and adjust the image accordingly as the eye’s focus changes relatively slowly it should be possible to keep up. In short, move the problem from the physical display and optics domain (that will remain costly and problematical), to the sensor and processing domain (that will more rapidly come down in cost).

If I’m at Hololens, ODG, or any other company working on an AR/MR systems and accept that vergence/accommodation is a problem needs to be to solve, I’m going to solve it with eye/pupil sensing and processing, not by screwing up everything else by doing it with optics and displays. ML’s competitors have had enough warning to already be well into developing solutions if they weren’t prior to ML making such a big deal about the already well known issue.

The question I’m left is if and when did Magic Leap figured this out and were they too committed by ego or what they told investors to focus planes to change at that point? I have not found evidence so far in their patent applications that they tried to changed course, but these patent applications will be about 18 months or more behind what they decided to do. But if they don’t use focus planes, they would have to admit that they are much closer to Hololens and other competitors than they would like the market to think.

Magic Leap – Fiber Scanning Display Follow UP

Some Newer Information On Fiber Scanning

Through some discussions and further searching I found some more information about Fiber Scanning Displays (FSD) that I wanted to share. If anything, this material further supports the contention that Magic Leap (ML) is not going to have a high resolution FSD anytime soon.

Most of the images available is about fiber scanning for use as a endoscope camera and not as a display device. The images are of things like body parts they really don’t show resolution or the amount of distortion in the image. Furthermore most of the images are from 2008 or older which gives quite a bit of time for improvement. I have found some information that was generated in the 2014 to 2015 time frame that I would like to share.

Ivan Yeoh’s 2015 PhD dissertation

2015-yeoh-laser-projection

In terms of more recent fiber scanning technology, Ivan Yeoh’s name seems to be a common link. Show at left is a laser projected image and the source test pattern from Ivan Yeoh’s 2015 PhD dissertation “Online Self-Calibrating Precision Scanning Fiber Technology with Piezoelectric Self-Sensing“at the University of Washington. It is the best quality image of a test pattern or known image that I have found of a FSD anywhere. The dissertation is about how to use feedback to control the piezoelectric drive of the fiber. While his paper is about the endoscope calibration, he nicely included this laser projected image.

The drive resulted in 180 spirals which would nominally be 360 pixels across at the equator of the image with a 50Hz frame rate. But based on the resolution chart, the effective resolution is about 1/8th of that or only ~40 pixels, but about half of this “loss” is due to resampling a rectilinear image onto the spiral. You should also note that there is considerably more distortion in the center of the image where the fiber will be moving more slowly.

2015-yeoh-endoscope-manual-calibrationYeoh also included some good images at right showing how had previously used a calibration setup to manually calibrate the endoscope before use as it would go out of calibration with various factors including temperature. These are camera images and based on the test charts they are able to resolve about 130 pixels across which is pretty close to the Nyquist sampling rate from a 360 samples across spiral. As expected the center of the image where the fiber is moving the slowest is the most distorted.

While a 360 pixel camera is still very low resolution by today’s standards, it is still 4 to 8 times better than the resolution of the laser projected image. Unfortunately Yeoh was concerned with distortion and does not really address resolution issues in his dissertation. My resolution comments are based on measurements I could make from the images he published and copied above.

Washington Patent Application Filed in 2014

uow-2016-fsd-applicationYeoh is also the lead inventor on the University of Washington patent application US 2016/0324403 filed in 2014 and published in June 2016. At left is Fig. 26 from that application. It is supposed to be of a checkerboard pattern which you may be able to make out. The figure is described as using a “spiral in and spiral out” process where the rather than having a retrace time, they just reverse the process. This applications appears to be related to Yeoh’s dissertation work. Yeoh is shown as living in Fort Lauderdale, FL on the application, near Magic Leap headquarters.   Yeoh is also listed as an inventor on the Magic Leap application US 2016/0328884 “VIRTUAL/AUGMENTED REALITY SYSTEM HAVING DYNAMIC REGION RESOLUTION” that I discuss in my last article. It would appear that Yeoh is or has worked for Magic Leap.

2008 YouTube Video

ideal-versus-actually-spiral-scan

Additionally, I would like to include some images from a 2008 YouTube Video that kmanmx from the Reddit Magic Leap subreddit alerted me to. White this is old, it has a nice picture of the fiber scanning process both as a whole and with close-up image near the start of the spiral process.

For reference on the closeup image I have added the size of a “pixel” for a 250 spiral / 500 pixel image (red square) and what a 1080p pixel (green square) would be if you cropped the circle to a 16:9 aspect ratio. As you hopefully can see the spacing and jitter variations-error in the scan process are several 1080p pixels in size. While this information is from 2008, the more recent evidence above does not show a tremendous improvement in resolution.

Other Issues

So far I have mostly concentrated on the issue of resolution, but there are other serious issues that have to be overcome. What is interesting in the Magic Leap and University of Washington patent literature is the lack of patent activity to address the other issues associated with generating a fiber scanned image. If Magic Leap were serious and had solved these issues with FSD, one would expect to see patent activity in making FSD work at high resolution.

One major issue that may not be apparent to the casual observer is the the controlling/driving the lasers over an extremely large dynamic range. In addition to support the typical 256 (8-bits) per color and supporting overall brightness adjustment based on the ambient light, the speed of the scan varies by a large amount an they must compensate for this or end up with a very bright center where the scan is moving more slowly. When you combine it all together they would seem to need to control the lasers over a greater than 2000:1 dynamic range from a dim pixel at the center to a brightest pixel at the periphery.

Conclusion

Looking at all the evidence there is just nothing there to convince me that Magic Leap is anywhere close to having perfected a FSD to the point that it could be competitive with a conventional display device like LCOS, DLP or Micro-OLED, not less the 50 megapixel resolutions they talk about. Overall, there is reasons to doubt that a electromechanical scan process is going to in the long run compete with an all electronic method.

It very well could be that Magic Leap had hoped that FSD would work and/or it was just a good way to convince investors that they had a technology that would lead to super high resolution in the future. But there is zero evidence that have seriously improved on what the University of Washington has done. They may still be pursuing it as an R&D effort but there is no reason to believe that they will have it in a product anytime soon.

All roads point to ML using either LCOS (per Business Insider of October 2016) or a DLP based what I have heard is in some prototypes. This would mean they will likely have either 720p or 1080p resolution display, or the same as others such as Hololens (which will likely have a 1080p version soon).

The whole FSD is about trying to break through the physical pixel barrier of conventional technologies.  There are various physics (diffraction is becoming a serious issue) and material issues that will likely make it tough to make physical pixels much smaller than 3 micron.

Even if there was a display resolution breakthrough (which I doubt based on the evidence), there are issues as to whether this resolution could make it through the optics. As the resolution improves the optics have to also improve or else they will limit the resolution. This is a factor that particularly concerns me with the waveguide technologies I have seen to date that appear to be at the heart of Magic Leap optics.

Magic Leap – The Display Technology Used in their Videos

So, what display technology is Magic Leap (ML) using, at least in their posted videos?   I believe the videos rule out a number of the possible display devices, and by a process of elimination it leaves only one likely technology. Hint: it is NOT laser fiber scanning prominently shown number of ML patents and article about ML.

Qualifiers

Magic Leap, could be posting deliberately misleading videos that show technology and/or deliberately bad videos to throw off people analyzing them; but I doubt it. It is certainly possible that the display technology shown in the videos is a prototype that uses different technology from what they are going to use in their products.   I am hearing that ML has a number of different levels of systems.  So what is being shown in the videos may or may not what they go to production with.

A “Smoking Gun Frame” 

So with all the qualifiers out of the way, below is a frame capture from Magic Leaps “A New Morning” while they are panning the headset and camera. The panning actions cause temporal (time based) frame shutter artifact in the form of partial ghost images as a result of the camera and the display running asynchronously and/or different frame rates. This one frame along with other artifacts you don’t see when playing the video, tells a lot about the display technology used to generate the image.

ml-new-morning-text-images-pan-leftIf you look at the left red oval you will see at the green arrow a double/ghost image starting and continuing below that point.  This is where the camera caught the display in its display update process. Also if you look at the right side of the image you will notice that the lower 3 circular icons (in the red oval) have double images where the top one does not (the 2nd to the top has a faint ghost as it is at the top of the field transition). By comparison, there is not a double image of the real world’s lamp arm (see center red oval) verifying that the roll bar is from the ML image generation.

ml-new-morning-text-whole-frameUpdate 2016-11-10: I have upload for those that would want to look at it.   Click on the thumbnail at left to see the whole 1920×1080 frame capture (I left the highlighting ovals that I overlaid).

Update 2016-11-14 I found a better “smoking gun” frame below at 1:23 in the video.  In this frame you can see the transition from one frame to the next.  In playing the video the frame transition slowly moves up from frame to frame indicating that they are asynchronous but at almost the same frame rate (or an integer multiple thereof like 1/60 or 1/30th)

ml-smoking-gun-002

 In addition to the “Smoking Gun Frame” above, I have looked at the “A New Morning Video” as well the “ILMxLAB and ‘Lost Droids’ Mixed Reality Test” and the early “Magic Leap Demo” that are stated to be “Shot directly through Magic Leap technology . . . without use of special effects or compositing.”through the optics.”   I was looking for any other artifacts that would be indicative of the various possible technologies

Display Technologies it Can’t Be

Based on the image above and other video evidence, I think it save to rule out the following display technologies:

  1. Laser Fiber Scanning Display – either a single or multiple  fiber scanning display as shown in Magic Leaps patents and articles (and for which their CTO is famous for working on prior to joining ML).  A fiber scan display scans in a spiral (or if they are arrayed an array of spirals) with a “retrace/blanking” time to get back to the starting point.  This blanking would show up as diagonal black line(s) and/or flicker in the video (sort of like an old CRT would show up with a horizontal black retrace line).  Also, if it is laser fiber scanning, I would expect to see evidence of laser speckle which is not there. Laser speckle will come through even if the image is out of focus.  There is nothing to suggest in this image and its video that there is a scanning process with blanking or that lasers are being used at all.  Through my study of Laser Beam Scanning (and I am old enough to have photographed CRTs) there is nothing in the still frame nor videos that is indicative of a scanning processes that has a retrace.
  2. Field Sequential DLP or LCOS – There is absolutely no field sequential color rolling, flashing, or flickering in the video or in any still captures I have made. Field sequential displays, display only one color at a time very rapidly. When these rapid color field changes beat against the camera’s scanning/shutter process.  This will show up as color variances and/or flicker and not as a simple double image. This is particularly important because it has been reported that Himax which makes field sequential LCOS devices, is making projector engines for Magic Leap. So either they are not using Himax or they are changing technology for the actual product.  I have seen many years of DLP and LCOS displays both live and through many types of video and still cameras and I see nothing that suggest field sequential color is being used.
  3. Laser Beam Scanning with a mirror – As with CRTs and fiber scanning, there has to be a blanking/retrace period between frames will show up in the videos as roll bar (dark and/or light) and it would roll/move over time.  I’m including this just to be complete as this was never suggested anywhere with respect to ML.
UPDATE Nov 17, 2016

Based on other evidence that as recently come in, even though I have not found video evidence of Field Sequential Color artifacts in any of the Magic Leap Videos, I’m more open to thinking that it could be LCOS or (less likely) DLP and maybe the camera sensor is doing more to average out the color fields than other cameras I have used in the past.  

Display Technologies That it Could Be 

Below are a list of possible technologies that could generate video images consistent with what has been shown by Magic Leap to date including the still frame above:

  1. Mico-OLED (about 10 known companies) – Very small OLEDs on silicon or similar substrates. As list of the some of the known makers is given here at OLED-info (Epson has recently joined this list and I would bet that Samsung and others are working on them internally). Micro-OLEDs both A) are small enough toinject an image into a waveguide for a small headset and B) has the the display characteristics that behave the way the image in the video is behaving.
  2. Transmissive Color Filter HTPS (Epson) – While Epson was making transmissive color filter HTPS devices, their most recent headset has switch to a Micro-OLED panel suggesting they themselves are moving away.  Additionally while Meta first generation used Epson’s HTPS, they moved away to a large OLED (with a very large spherical reflective combiner).  This technology is challenged in going to high resolution and small size.
  3. Transmissive Color Filter LCOS (Kopin) – is the only company making Color Filter Transmissive LCOS but they have not been that active as of last as a component supplier and they have serious issues with a roadmap to higher resolution and size.
  4. Color Filter reflective LCOS– I’m putting this in here more for completeness as it is less likely.  While in theory it could produce the images, it generally has lower contrast (which would translate into lack of transparency and a milkiness to the image) and color saturation.   This would fit with Himax as a supplier as they have color filter LCOS devices.
  5. Large Panel LCD or OLED – This would suggest a large headset that is doing something similar to the Meta 2.   Would tend to rule this out because it would go against everything else Magic Leap shows in their patents and what they have said publicly.   It’s just that it could have generated the image in the video.
And the “Winner” is I believe . . . Micro-OLED (see update above) 

By a process of elimination including getting rid of the “possible but unlikely” ones from above, it strongly points to it being Micro-OLED display device. Let me say, I have no personal reason to favor it being Micro-OLED, one could argue it might be to my advantage based on my experience for it to be LCOS if anything.

Before I started any serious analysis, I didn’t have an opinion. I started out doubtful that it was field sequential or and scanning (fiber/beam) devices due to the lack of any indicative artifacts in the video, but it was the “smoking gun frame” that convince me that that if the camera was catching temporal artifacts, it should have been catching the other artifact.

I’m basing this conclusions on the facts as I see them.  Period, full stop.   I would be happy to discuss this conclusion (if asked rationally) in the comments section.

Disclosure . . . I Just Bought Some Stock Based on My Conclusion and My Reasoning for Doing So

The last time I played this game of “what’s inside” I was the first to identify that a Himax LCOS panel was inside Google Glass which resulted in their market cap going up almost $100M in a couple of hours.  I had zero shares of Hixmax when this happened, my technical conclusion now as it was then was based on what I saw.

Unlike my call on Himax in Google Glass I have no idea which company make the device Magic Leap appears to using nor if Magic Leap will change technologies for their production device.  I have zero inside information and am basing this entirely on the information I have given above (you have been warned).   Not only is the information public, but it is based on videos that are many months old.

I  looked at companie on the OLED Microdisplay List by www.oled-info.com (who has followed OLED for a long time).  It turned out all the companies were either part of a very large company or were private companies, except for one, namely eMagin.

I have know of eMagin since 1998 and they have been around since 1993.  They essentially mirror Microvision doing Laser Beam Scanning and was also founded in 1993, a time where you could go public without revenue.  eMagin has spent/loss a lot of shareholder money and is worth about 1/100th from their peak in March 2000.

I have NOT done any serious technical, due diligence, or other stock analysis of eMagin and I am not a stock expert. 

I’m NOT saying that eMagine is in Magic Leap. I’m NOT saying that Micro-OLED is necessarily better than any other technology.  All I am saying is that I think that someone’s Micro-OLED technology is being using the Magic Leap prototype and that Magic Leap is such hotly followed company that it might (or might not) affect the stock price of companies making Micro-OLEDs..

So, unlike the Google Glass and Himax case above, I decided to place a small “stock bet” (for me) on ability to identify the technology (but not the company) by buying some eMagin stock  on the open market at $2.40 this morning, 2016-11-09 (symbol EMAN). I’m just putting my money where my mouth is so to speak (and NOT, once again, stock advice) and playing a hunch.  I’m just making a full disclosure in letting you know what I have done.

My Plans for Next Time

I have some other significant conclusions I have drawn from looking at Magic Leap’s video about the waveguide/display technology that I plan to show and discuss next time.

Near Eye AR/VR and HUD Metrics For Resolution, FOV, Brightness, and Eyebox/Pupil

Image result for oculus riftI’m planning on following up on my earlier articles about AR/VR Head Mounted Displays
(HMD) that also relate to Heads Up Displays (HUD) with some more articles, but first I would like to get some basic Image result for hololenstechnical concepts out of the way.  It turns out that the metrics we care about for projectors while related don’t work for hud-renaultmeasuring HMD’s and HUDs.

I’m going to try and give some “working man’s” definitions rather than precise technical definitions.  I be giving a few some real world examples and calculations to show you some of the challenges.

Pixels versus Angular Resolution

Pixels are pretty well understood, at least with today’s displays that have physical pixels like LCDs, OLEDs, DLP, and LCOS.  Scanning displays like CRTs and laser beam scanning, generally have additional resolution losses due to imperfections in the scanning process and as my other articles have pointed out they have much lower resolution than the physical pixel devices.

When we get to HUDs and HMDs, we really want to consider the angular resolution, typically measured in “arc-minutes” which are 1/60th of a degree; simply put this is the angular size that a pixel covers from the viewing position. Consumers in general haven’t understood arc-minutes, and so many companies have in the past talked in terms of a certain size and resolution display viewed from a given distance; for example a 60-inch diagonal 1080P viewed at 6 feet, but since the size of the display, resolution and viewing distance are all variables its is hard to compare displays or what this even means with a near eye device.

A common “standard” for good resolution is 300 pixels per inch viewed at 12-inches (considered reading distance) which translates to about one-arc-minute per pixel.  People with very good vision can actually distinguish about twice this resolution or down to about 1/2 an arc-minute in their central vision, but for most purposes one-arc-minute is a reasonable goal.

One thing nice about the one-arc-minute per pixel goal is that the math is very simple.  Simply multiply the degrees in the FOV horizontally (or vertically) by 60 and you have the number of pixels required to meet the goal.  If you stray much below the goal, then you are into 1970’s era “chunky pixels”.

Field of View (FOV) and Resolution – Why 9,000 by 8100 pixels per eye are needed for a 150 degree horizontal FOV. 

As you probably know, the human eye’s retina has variable resolution.  The human eyes has roughly elliptical FOV of about 150 to 170 degrees horizontally by 135 to 150 degrees vertically, but the generally good discriminating FOV is only about 40 degree (+/-20 degrees) wide, with reasonably sharp vision, the macular, being about 17-20 degrees and the fovea with the very best resolution covers only about 3 degrees of the eye’s visual field.   The eye/brain processing is very complex, however, and the eye moves to aim the higher resolving part of the retina at a subject of interest; one would want the something on the order of the one-arc-minute goal in the central part of the display (and since having a variable resolution display would be a very complex matter, it end up being the goal for the whole display).

And going back to our 60″, 1080p display viewed from 6 feet, the pixel size in this example is ~1.16 arc-minutes and the horizontal field of view of view will be about 37 degrees or just about covering the generally good resolution part of the eye’s retina.

Image result for oculus rift

Image from Extreme Tech

Now lets consider the latest Oculus Rift VR display.  It spec’s 1200 x 1080 pixels with about a 94 horz. by 93 vertical FOV per eye or a very chunky ~4.7 arc-minutes per pixel; in terms of angular resolution is roughly like looking at a iPhone 6 or 7 from 5 feet away (or conversely like your iPhone pixels are 5X as big).   To get to the 1 arc-minute per pixel goal of say viewing today’s iPhones at reading distance (say you want to virtually simulate your iPhone), they would need a 5,640 by 5,580 display or a single OLED display with about 12,000 by 7,000 pixels (allowing for a gap between the eyes the optics)!!!  If they wanted to cover the 150 by 135 FOV, we are then talking 9,000 by 8,100 per eye or about a 20,000 by 9000 flat panel requirement.

Not as apparent but equally important is that the optical quality to support these types of resolutions would be if possible exceeding expensive.   You need extremely high precision optics to bring the image in focus from such short range.   You can forget about the lower cost and weight Fresnel optics (and issues with “God rays”) used in Oculus Rift.

We are into what I call “silly number territory” that will not be affordable for well beyond 10 years.  There are even questions if any know technology could achieve these resolutions in a size that could fit on a person’s head as there are a number of physical limits to the pixel size.

People in gaming are apparently living with this appallingly low (1970’s era TV game) angular resolution for games and videos (although the God rays can be very annoying based on the content), but clearly it not a replacement for a good high resolution display.

Now lets consider Microsoft’s Hololens, it most criticized issue is is smaller (relative to the VR headsets such as Oculus) FOV of about 30 by 17.5 degrees.  It has a 1268 by 720 pixel display per eye which translates into about 1.41 arc-minutes per pixel which while not horrible is short of the goal above.   If they had used 1920×1080 (full HD) microdisplay devices which are becoming available,  then they would have been very near the 1 arc-minute goal at this FOV.

Let’s understand here that it is not as simple as changing out the display, they will also have to upgrade the “light guide” that the use as an combiner to support the higher resolution.   Still this is all reasonably possible within the next few years.   Microsoft might even choose to grow the FOV to around 40 degrees horizontally rather and keep the lower angular resolution a 1080p display.  Most people will not seriously notice the 1.4X angular resolution different (but they will by about 2x).

Commentary on FOV

I know people want everything, but I really don’t understand the criticism of the FOV of Hololens.  What we can see here is a bit of “choose your poison.”  With existing affordable (or even not so affordable) technology you can’t support a wide field of view while simultaneously good angular resolution, it is simply not realistice.   One can imaging optics that would let you zoom between a wide FOV with lower angular resolution and a smaller FOV with higher angular resolution.  The control of this zooming function could perhaps be controlled by the content or feedback from the user’s eyes and/or brain activity.

Lumens versus Candelas/Meter2 (cd/m2 or nits)

With an HMD or HUD, what we care about is the light that reaches the eye.   In a typical front projector system, only an extremely small percentage of the light that goes out of the projector, reflects off the screen and makes it back to any person’s eye, the vast majority of the light goes to illuminating the room.   With a HMD or HUD all we care about is the light that makes it into the eye.

Projector lumens or luminous flux, simply put, are a measure of the total light output and for a projector is usually measure when outputting a solid white image.   To get the light that makes it to the eye we have to account for the light hits a screen, and then absorbed, scattered, and reflects back at an angle that will get back to the eye.  Only an exceeding small percentage (a small fraction of 1%) of the projected light will make it into the eye in a typical front projector setup.

With HMDs and HUDs we talk about brightness in terms candelas-per-Meter-Squared (cd/m2), also referred to as “nits” (while considered an obsolete term, it is still often used because it is easier to write and say).  Cd/m2 (or luminance) is measure of brightness in a given direction which tells us how bright the light appears to the eye looking in a particular direction.   For a good quick explanation of lumens, cd/m2 I would recommend a Compuphase article.

Image result for hololens

Hololens appears to be “luminosity challenged” (lacking in  cd/m2) and have resorted to putting sunglasses on outer shield even for indoor use.  The light blocking shield is clearly a crutch to make up for a lack of brightness in the display.   Even with the shield, it can’t compete with bright light outdoors which is 10 to 50 times brighter than a well lit indoor room.

This of course is not an issue for the VR headsets typified by Oculus Rift.  They totally block the outside light, but it is a serious issue for AR type headsets, people don’t normally wear sunglasses indoors.

Now lets consider a HUD display.  A common automotive spec for a HUD in sunlight is to have 15,000 cd/m2 whereas a typical smartphone is between 500 and 600 cd/m2 our about 1/30th the luminosity of what is needed.  When you are driving a car down the road, you may be driving in the direction of the sun so you need a very bright display in order to see it.

The way HUDs work, you have a “combiner” (which may be the car’s windshield) that combines the image being generated with the light from the real world.  A combiner typical only reflects about 20% to 30% of the light which means that the display before the combiner needs to have on the order of 30,000 to 50,000 cd/m2 to support the 15,000 cd/m2 as seen in the combiner.  When you consider that you smartphone or computer monitor only has about 400 to 600 cd/m2 , it gives you some idea of the optical tricks that must be played to get a display image that is bright enough.

phone-hudYou will see many “smartphone HUDs” that simply have a holder for a smarphone and combiner (semi-mirror) such as the one pictured at right on Amazon or on crowdfunding sites, but rest assured they will NOT work in bright sunlight and only marginal in typical daylight conditions. Even with combiners that block more than 50% of the daylight (not really much of a see-through display at this point) they don’t work in daylight.   There is a reason why companies are making purpose built HUDs.

The cd/m2 also is a big issue for outdoor head mount display use. Depending on the application, they may need 10,000 cd/m2 or more and this can become very challenging with some types of displays and keeping within the power and cooling budgets.

At the other extreme at night or dark indoors you might want the display to have less than 100 cd/m2 to avoid blinding the user to their surrounding.  Note the SMPTE spec for movie theaters is only about 50 cd/mso even at 100 cd/m2 you would be about 2X the brightness of a movie theater.  If the device much go from bright sunlight to night use, you could be talking over a 1,500 to 1 dynamic range which turns out to be a non-trivial challenge to do well with today’s LEDs or Lasers.

Eye-Box and Exit Pupil

Since AR HMDs and HUDs generate images for a user’s eye in a particular place, yet need to compete with the ambient light, the optical system is designed to concentrate light in the direction of the eye.  As a consequence, the image will only be visible in a given solid angle “eye-box” (with HUDs) or “pupil” (with near eye displays).   There is also a trade-off in making the eyebox or pupil bigger and the ease of use, as the bigger the eye-box or pupil, the easier it will be the use.

With HUD systems there can be a pretty simple trade-off in eye-box size and cd/m2 and the lumens that must be generated.   Using some optical tricks can help keep from needing an extremely bright and power hungry light source.   Conceptually a HUD is in some ways like a head mounted display but with very long eye relief. With such large eye relieve and the ability of the person to move their whole head, the eyebox for a HUD has significantly larger than the exit pupil of near eye optics.  Because the eyebox is so much larger a HUD is going to need much more light to work with.

For near eye optical design, getting a large exit pupil is a more complex issue as it comes with trade-offs in cost, brightness, optical complexity, size, weight, and eye-relief (how far the optics are from the viewer’s eye).

Too small a pupil and/or with more eye-relief, and a near eye device is difficult to use as any small movement of the device causes you to to not be able to see the whole image.  Most people’s first encounter with an exit pupil is with binoculars or a telescope and how the image cuts offs unless the optics are centered well on the user’s eye.

Conclusions

While I can see that people are excited about the possibilities of AR and VR technologies, I still have a hard time seeing how the numbers add up so to speak for having what I would consider to be a mass market product.  I see people being critical of Hololens’ lower FOV without being realistic about how they could go higher without drastically sacrificing angular resolution.

Clearly there can be product niches where the device could serve, but I think people have unrealistic expectations for how fast the field of view can grow for product like Hololens.   For “real work” I think the lower field of view and high angular resolution approach (as with Hololens) makes more sense for more applications.   Maybe game players in the VR space are more willing to accept 1970’s type angular resolution, but I wonder for how long.

I don’t see any technology that will be practical in high volume (or even very expensive at low volume) that is going to simultaneously solve the angular resolution and FOV that some people want. AR displays are often brightness challenged, particularly for outdoor use.  Layered on top of these issues are those size, weight, cost, and power consumption which we will have to save these issues for another day.

 

Wrist Projector Scams – Ritot, Cicret, the new eyeHand

ritot-cicret-eyehand-001Wrist Projectors are the crowdfund scams that keeps on giving with new ones cropping up every 6 months to a year. When I say scam, I mean that there is zero chance that they will ever deliver anything even remotely close what they are promising. They have obviously “Photoshopped”/Fake pictures to “show” projected images that are not even close to possible in the the real world and violate the laws of physics (are forever impossible). While I have pointed out in this blog where I believe that Microvision has lied and mislead investors and showed very fake images with the laser beam scanning technology, even they are not total scammers like Ritot, Cicret, and eyeHand.

According to Ritot’s Indiegogo campaign, they have taken in $1,401,510 from 8917 suckers (they call them “backers”).   Cicret according to their website has a haul of $625,000 from 10,618 gullible people.

Just when you think that Ritot and Cicret had found all the suckers for wrist projectors, now CrowdFunder reports that eyeHand has raised $585,000 from individuals and claims to have raised another $2,500,000 in equity from “investors” (if they are real then they are fools, if not, then it is just part of the scam). A million here, $500K there, pretty soon you are talking real money.

Apparently Dell’s marking is believing these scams (I would hope their technical people know better) and has show video Ads that showed a similar impossible projectors.  One thing I will give them is that they did a more convincing “simulation” (no projecting “black”) and they say in the Ads that these are “concepts” and not real products. See for example the following stills from their Dell’s videos (click to see larger image).  It looks to me like they combined a real projected image (with the projector off camera and perpendicular to the arm/hand) and then add fake projector rays to try and suggest it came from the dummy device on the arm): dell-ritots-three

Ritot was the first of these scams I was alerted to and I help contribute some technical content to the DropKicker article http://drop-kicker.com/2014/08/ritot-projection-watch/. I am the “Reader K” that they thanked in the author’s note at the beginning of the article.  A number of others have called out the Ritot and Cicret as being scams but that did not keep them from continuing to raise money nor has it stopped the new copycat eyeHand scam.

The some of key problems with the wrist projector:

  1. Very shallow angle of projection.  Projectors normally project on a surface that is perpendicular to the direction of projection, but the wrist projectors have to project onto a surface that is nearly parallel to the direction of projection.  Their concepts show a projector that is only a few (2 to 4) millimeters above the surface. When these scammers later show “prototypes” they radically change the projection distance and projection angle.
  2. Extremely short projection distance.  The near side of the projection is only a few millimeters away while the far side of the image could be 10X or 50X further away.  There is no optics or laser scanning technology on earth that can do this.  There is no way to get such a wide image at such a short distance from the projector.  As light falls off with the square of distance, this results in an impossible illumination problem (the far side being over 100X dimmer than the near side).
  3. Projecting in ambient light – All three of the scammers show concept images where the projected image is darker than the surrounding skin.  This is absolutely impossible and violates the laws of physics.   The “black” of the image is set by the ambient light and the skin, the projector can only add light, it is impossible to remove light with a projector.  This shows ignorance and/or a callous regard for the the truth by the scammers.
  4. The blocking of the image by hairs, veins, and muscles.  At such a shallow angle (per #1 above) everything is in the way.
  5. There is no projector small enough.  These projector engines with their electronics that exist are more than 20X bigger in volume than what would be required to fit.
  6. The size of the orifice through with the light emerges is too small to support the size of the image that they want to project
  7.  The battery required to make them daylight readable would be bigger than the whole projector that they show.  These scammers would have you believe that a projector could work off a trivially small battery.
  8. Cicret and eyeHand show “touch interfaces” that won’t work due to the shallow angle.  The shadows cast by fingers working the touch interface would block the light to the rest of the image and made “multi-touch” impossible.   This also goes back to the shallow angle issue #1 above.

The issues above hold true whether the projection technology uses DLP, LCOS, or Laser Beam Scanning.

Cicret and Ritot have both made “progress reports” showing stills and  videos using projectors more than 20 times bigger and much higher and farther away (to reduce the projection angle) than the sleek wrist watch models they show in their 3-D CAD models.   Even then they  keep off-camera much/most of the electronics and battery/power-supply necessary needed to drive the optics that the show.

The image below is from a Cicret “prototype” video Feb of 2015 where they simply strapped a Microvision ShowWX+ HMDI upside down to a person’s wrist (I wonder how many thousand dollars they used engineering this prototype). They goofed in the video and showed enough of the projector that I could identify (red oval) the underside of the Microvision projector (the video also shows the distinctive diagonal roll bar of a Microvision LBS projector).  I have show the rest of the projector roughly to scale in the image below that they cropped off when shooting the video.  What you can’t tell in this video is that the projector is also a couple of inches above the surface of the arm in order to project a reasonable image.

cicret-001b

So you might think Cicret was going to use laser beam scanning, but no, their October 2016 “prototype” is showing a panel (DLP or LCOS) projector.  Basically it looks like they are just clamping whatever projector they find to a person’s wrist, there is no technology they are developing.  In this latest case, it looks like what they have done is found a small production projector taken its guts out and put it in a 3-D printed case.  Note the top of the case is going to be approximately 2 inches above a person’s wrist and how far away the image is from the projector.

cicret-002e

Ritot also has made update to keep their suckers on the hook.   Apparently Indiegogo only rule is that you much keep lying to your “backers” (for more on the subject of how Indiegogo condones fraud click here).  These updates at best show how little these scammers understood projection technology.   I guess one could argue that they were too incompetent to know they were lying.  ritot-demo-2014

On the left is a “demo” Ritot shows in 2014 after raising over $1M.  It is simply an off the shelf development system projector and note there is no power supply.  Note they are showing it straight on/perpendicular to the wrist from several inches away.

ritot-2015By 2015 Rito had their own development system and some basic optics.  Notice how big the electronics board is relative to the optics and that even this does not show the power source.

By April 2016 they showed an optical engine (ONLY) strapped to a persons wrist.  ritot-2016-04-20-at-25sCut off in the picture is the all the video drive electronics (see the flex cable in the red oval) that is off camera and likely a driver board similar to the one in the 2015 update  and the power supplies/battery.

In the April 2016 you should notice how the person’s wrist is bent to make make it more perpendicular to the direction of the projected image.  Also not that the image is distorted and about the size of an Apple watch’s image.   I will also guarantee that you will not have a decent view-able image when used outdoors in daylight.

The eyeHand scam has not shown anything like a prototype, just a poorly faked (projecting black) image.  From the low angle they show in their fake image, the projected would be blocked by the base of the thumb even if the person hold their hand flat.  To make it work at all they would have to move the projector well up the person’s arm and then bend the wrist, but then the person could not view it very well unless they hold their arm at an uncomfortable angle.  Then you have the problem of keeping the person from moving/relaxing their wrist and loosing the projection surface.   And of course it would not be view-able outdoors in daylight.

It it not like others have been trying to point out that these projectors are scams.  Google search “Ritot scam” or “Cicret scam” and you will find a number of references.  As best I can find, this blog is the first to call out the eyeHand scam:

  • The most technically in depth article was by Drop-Kicker on the Ritot scam
  • Captain Delusional has a  comic take on the Cicret scam on YouTube – He has some good insights on the issue of touch control but also makes some technical mistakes such as his comments on laser beam scanning (you can’t remove the laser scanning roll-bar by syncing the camera — also laser scanning has the same fall-off in brightness due do the scanning process).
  • Geek Forever had an article on the Ritot Scam 
  • A video about the Ritot Scam on Youtube
  • KickScammed about Ritot from 2014

The problem with scam startups is that they tarnish all the other startups trying to find a way to get started.  Unfortunately, the best liars/swindlers often do the best with crowdfunding.  The more they are willing to lie/exaggerate, the better it makes their product sound.

Indiegogo has proven time and again to have extremely low standards (basically if the company keep posting lies, they are good to go – MANY people tried to tell Indiegogo about the Ritot Scam but to no avail before Ritot got the funds). Kickstarter has some standards but the bar is not that large but at least I have not see a wrist projector on Kickstarter yet. Since the crowdfunding sites get a cut of the action whether the project delivers or not, their financial incentives are on the side of the companies and the people funding. There is no bar for companies that go with direct websites, it is purely caveat emptor.

I suspect that since the wrist projector scam has worked at least three (3) times so far, we will see other using it.   At least with eyeHand you have a good idea of what it will look like in two years (hint – like Ritot and Cicret).

Laser Beam Scanning Versus Laser-LCOS Resolution Comparison

cen-img_9783-celluon-with-uo

Side By Side Center Patterns (click on image for full size picture)

I apologize for being away for so long.  The pictures above and below were taken over a year ago and I meant to format and publish them back then but some other business and life events got in the way.

The purpose of this article is to compare the resolution of the Celluon PicoPro Laser Beam Scanning (LBS) projector and the UO Smart Beam Laser LCOS projector.   This is not meant to be a full review of both products, although I will make a few comments here and there, but rather, it is to compare the resolution between the two products.  Both projectors claim to have 720P resolution but only one of them actually has that “native/real” resolution.

This is in a way a continuation of the serious I have written about the PicoPro with optics developed by Sony and the beam scanning mirror and control by Microvision and in particular articles http://wp.me/p20SKR-gY and http://wp.me/p20SKR-hf.  With this article I am now included some comparison pictures I took of the UO Smart Beam projector (https://www.amazon.com/UO-Smart-Beam-Laser-Projector-KDCUSA/dp/B014QZ4FLO).

As per my prior articles, the Celluon PicoPro has no where close to it stated 1920×720 (non-standard) nor even 1280×720 (720P) resolution.  The UO projector while not perfect, does demonstrate 720P resolution reasonably well, but it does suffer from chroma aberrations (color separation) at the top of the image due to optical 100% offset (this is to be expected to some extent).

Let me be up front, I worked on the LCOS panel used in the UO projector when I was at Syndiant but I had nothing to do with the UO projector itself.   Take that as bias if you want, but the pictures I think tell the story.  I did not have any contact with either UO (nor Celluon for that matter) in preparing this article.

I also want to be clear that both the UO projector and the Celluon PicoPro tested are now over 1 year old and there may have been improvements since then.  I saw serious problems with both products, in particular with the color balance, the Celluon is too red (“white” is pink) and the UO very red deficient (“whilte is significantly blue-green).   The color is so far off on the Celluon that it would be a show stopper for me ever wanting to buy one as a consumer (hopefully UO has or will fix this).   Frankly, I think both projectors have serious flaws (if you want to know more, ask and I will write a follow-up article).

The UO Smart Beam had the big advantage in that it has “100% offset” which means that when placed on table-top, it will project upward not hitting the table without any keystone.   The PicoPro has zero offset and shoots straight out.  If you put it flat on a table the lower half of the image will shoot into the tabletop. Celluon includes a cheap and rather silly monopod that you can used to have the projector “float” above the table surface and then you can tilt it up and get a keystone image.  To take the picture, I had to mount the PicoPro on a much taller tripod and then shoot over the Projector so the image would not be keystoned

I understand that the next generation of the Celluon and a similar Sony MPCL1 projector (which has a “kickstand) have “digital keystone correction” which is not as good a solution as 100% offset as it reduces the resolution of the image; this is the “cheap/poor” way out and they really should have 100% offset like the UO projector (interestingly, earlier Microvision ShowWX projector with lower resolution had 100% offset) .

For the record – I like the Celluon PicoPro flatter form factor better; I’m not a fan of the UO cube as hurts the ability to put the projector in one’s pocket or a typical carrying bag.

Both the PicoPro with laser scanning and the Smart Beam with lasers illuminating an LCOS microdisplay have no focus knob and have a wide focus range (from about 50cm/1.5 feet to infinity), although they are both less sharp at the closer range.  The PicoPro with LBS is a Class 3R laser product whereas the Smart Beam with laser “illumination” of LCOS is only Class 1.   The measure dbrightness of the PicoPro was about 32 Lumens as rated when cold but dropped under 30 when heated up.  The UO while rated at 60 lumens was about 48 lumens when cold and about 45 when warmed up or more significantly below its “spec.”

Now onto the main discussion of resolution.  The picture at the top of this article shows the center crop from 720P test pattern generated by both projectors with the Smart Beam image on the left and the PicoPro on the right.   There is also an inset of the Smart Beam’s 1 pixel wide text pattern near the PicoPro’s 1 pixel wide pattern for comparison This test pattern shows a series of 1 pixel, 2 pixel and 3 pixel wide horizontal and vertical lines.

What you should hopefully notice is that the UO clearly resolves even the 1 pixel wide lines and the black lines are black whereas the 1 pixel wide lines are at best blurry and the 2 and even 3 pixel wide lines doe get to a very good black level (as in the contrast is very poor).  And the center is the very best case for the Celluon LBS whereas for the UO with it 100% offset it is a medium case (the best case is lower center).

The worst case for both projectors is one of the upper corners and below is a similar comparison of their upper right corner.  As before, I have included and inset of the UO’s single pixel image.

ur-img_9783-celluon-with-uo-overlay

Side By Side Center Patterns (click on image for full size picture)

What you should notice is that while there are still distinct 1 pixel wide lines in both directions in the UO projector, 1 pixel wide lines in the case of the Celluon LBS are a blurry mess.  Clearly they can’t resolve 1 pixel wide lines at 720P.

Because of the 100% offset optics the best case for the UO projector is at the bottom of the image (this is true almost any 100% offset optics) and this case is not much different than the center case for Celluon projector (see below):

lcen-celluon-with-uo-overlay

Below is a side by side picture I took (click on it for a full size image). The camera’s “white point” was an average between the two projectors (Celluon is too red/blue&green deficient and the UO is red deficient). The image below is NOT what I used in the cropped test patterns above as the 1 pixel features were too near the resolution limit of the Canon 70D camera (5472 by 3648 pixels) for the 1 pixel features.  So I used individual shots from each projector to double “sample” by the camera of the projected images.

side-by-side-img_0339-celluon-uo

For the Celluon PicoPro image I used the picture below (originally taken in RAW but digital lens corrected, cropped, and later converted to JPG for posting – click on image for full size):

img_9783-celluon-with-uo-overlay

For the UO Smart Beam image, I use the following image (also taken in RAW, digital lens corrected, straighten slightly, cropped and later converted to JPG for posting):

img_0231-uo-test-chart

As is my usual practice, I am including the test pattern (in lossless PNG format below for anyone who wants to verify and/or challenge my results:

interlace res-chart-720P G100A

I promise I will publish any pictures by anyone that can show better results with the PicoPro or any other LBS projector (Or UO projector for that matter) with the test pattern (or similar) above (I went to considerable effect to take the best possible PicoPro image that I could with a Canon 70D Camera).