Augmented Reality - Epson Moverio BT-300
#1  mdp 03-03-2019, 05:02 AM
I have spent three days using my first Augmented Reality device, the Epson Moverio BT-300 "Smart Glasses", (intended) as a mobile reading device.
In short, my judgement of the experience was: very, very rewarding, with some limitations and issues, and above expectations in most areas.

The device is an Android 5.x handheld, cable-connected to a thin and light "ear-nose mounted display" (spectacles) featuring two transparent Si-OLED, 1280x720 displays. Controls are on the handheld: arrows-touchpad (electrostatic d-pad), "Back-Home-History", pointer-trackpad and side buttons; I am not sure if further controls embedded in earphones could be used.

The colour of "black" will be interpreted as "transparent". Hence, the obtained visual effect is to have a 16:9 shaped virtual page of white (apart from formatting variations), well defined (but not always crisp) characters on a transparent background. It is like having, for example a 6 or 7 meters wide (~300'' diagonal) virtual screen at 10 meters distance (very rough calculations).
It is probably already the case to state: if you are using "black on white" on a backlit device (LCD, OLED etc.), you are very probably "doing it wrong" (if reflections get in the way, the screen was supposed to be matte/d and you have done it wrong). In the case of AR, this is especially true: you can of course have a "transparent on white" rendering, which in many cases will be the software default, instead of the correct "white on transparent", but that would be akin to having a panel stuck in front of you mounted on your head with a pole... It would cover the environment, including all the things your brain demands to see when around - that is not what you want. All decent software offers "inverted colours" mode (otherwise, the Android option to invert colours system-wise is available). You will see the scenery, and the screen content, with different focus at change of eye focus.

Pleasantly, the bet is won about the good effect of actually carrying a readable screen "on your nose" as you move around: the optimal environment for such reading is to walk outdoors - which was the intended use. More clearly and explicitly, the purpose was to protract intellectual exercise while living healthier places, postures and actions. The goal was met with unexpected excellence. In fact, it seems that psycho-perceptual properties are key in the well-functioning on the system - as on the contrary the device would perform very poorly if remaining static in a dark room; the good staticity of the screen with respect to the eyes and the variable background are very well and naturally, effortlessly, interpreted by the brain. This seems to compensate the still imperfect technology: an "analytical scrutiny", in static posture in a dark room, shows that the characters are mostly crisp but with blurry areas. The readability becomes much better if the eyes are set to project to a distant point. Other perceptual postures can vary the visual quality - for example, I am not sure that the blurry areas are fixed in space, and they may depend on "eye calibration and preparation" (for lack of better terms. With "preparation" I mean at least: after a few hours at a standard LCD computer monitor I wore the glasses and just everything was very blurry). During use, if at some moment you want to read e.g. small details like the time in a system or reader application statusbar, they may initially seem small faint small and unreadable, and soon become readable by better orienting your head. I used my natural (not 20/20) eyesight and have not tried wearing prescription glasses.
As written above, the scenery around you is always available, and so is the AR content, already at a change of eye focus.

I tested the system with Kingsoft Office and with Ivan (Foobnix) Ivanenko's Librera, and also with other documents reading software of mine based on the Android WebView, and with both free format documents (.doc, .html) and fixed format ones (.pdf), with blissful results.
Given the special (AR hardware) case, I found it very comfortable to read at a 12-lines-per-screen zoom, but - as forced for example by PDF formatting - also at 20-lines-per-screen zoom the text was fully readable, though really not as comfortable. Note that, since we are speaking of "lines", the 16:9 proportion is "quite short"; I would have loved a more square display, such as 1280x1280, and actually all the space would be there to exploit it (the darkened """projection""" screen, as also visible in the reconstructions I posted below, is squarey). With PDF, the "embolden" function in Librera is quite useful (with reference for example to the Sans-serif font used by O'Reilly, which tends to be quite thin). Both Kingsoft and Librera have full-screen functions; incidentally, some Kingsoft Office version may have a bad "white on black" implementation (washed out, "grey on grey") - there is an Android option to invert the colours at display level (at system level), in case the specific software application is imperfect.

You can normally scroll and change page with the arrows of the electrostatic d-pad, on the handheld which you can keep in your pocket. Of course, you could also have all Turing machines and shed enthusiasts offer: vocal controls through a peribuccal mike, BlueTooth tricks... I would love a smart glove to write (Jeff Hawking's "Palm") Graffiti gestures in the air - that would pleasantly solve the problem of typing. But I guess that also "speech-to-text" dictation is possible (and possibly more dignified).
EDIT: mentioning a "smart glove", or "air mouse", I forgot that this Moverio system already comprises the hardware: if the handheld part contains gyroscope, accelerometer etc. (unless they are only in the glasses, it could in theory be used as an air mouse - you could wave the handheld part in the air to move the mouse cursor. At the moment I cannot find a way (an option, an app) to make this work.

The battery, 3000 mAh, lasts for 5 hours. I am not sure this can be improved, outside of severe system hacking (but for the basic Airplane mode and GPS Off). GSam Battery Monitor seems to indicate that the display has a heavy impact (those small screens?), but I have not tried lowering the brightness, which I keep at around 80%, with the "mild sunglasses" plugin mounted; Epson (very high apparent manufacturing quality and provided material by the way) also bundled a "darker sunglasses" plugin which I have not yet tried.
But I could note that as I carry around a 10'000 mAh battery the hours could be increased to the full useful day, and that I am content with 5 hours per day as a reasonable amount for this kind of reading practice.

Technical specifications for the device are also found at

#2  mdp 03-06-2019, 07:26 AM
Extending the concept of reading to other related intellectual exercise, today I watched a University lesson on the device. Very rewarding. The impact increase on the battery was not much.

I also used other learning software, and again very pleasantly and effectively, but it was custom - using the dpad and having the right colors displayed is an asset.

#3  mdp 03-06-2019, 01:34 PM
Here are (imprecise and suffering from space constraints) reconstructions of the effect.
Beware that the zoom in the browser may blur the images. Load the attached in case.

image »

image »
epson_moverio_reconstruction_b1.jpg epson_moverio_reconstruction_b2.jpg 

#4  mdp 03-13-2019, 05:11 PM
In practice, with this kind of system and using some text rendering software, you may missed thicker fonts - they are easier on the eyes as the white text has to contrast against the scenery.

So I produced a thick version of the DejaVu, available here.

#5  mdp 03-14-2019, 06:43 PM
One note now especially about the parallel topic of video, but important in the context of "OLED outdoors".
The video experience, having watched a few hours of university lessons and interviews, seems to be close to excellent. And all done in the open sunlight. When done in the shade, e.g. in the car, it was like enjoying a "big screen" projected anywhere a comfortable position and an adequate background may match.

So I write this to stress a fleeting thought which may be unduly overlooked. OLED is typically terrible when getting even close to natural light (and they marketed it as "infinite contrast" - in some interpretation of the terms that make no sense in the real world).
So how come this implementation works so well?
Simply, with the use of the sun lenses plugins. Reducing with a simple trick the light that would wash out the display. It suggests the parallel of being able to dim the light around you while holding a palm-oriented OLED-based mobile device, enclosing you in a temporary bell to reduce excessive sunlight... Somehow, there is genius in it.

If a technology was implemented, to match the available one of setting the display brightness, to have adjustable intensity of the sun lenses, from transparent to obscuring with a few degrees in between, electronically selectable...

#6  jbiggley 03-17-2019, 02:51 PM
@mdp After spending the afternoon googling, I'm intrigued and delighted with your review of the Epson BT-300. The idea of an pseudo-AR reading experience is an exciting possibility. Honestly, I am surprised that an optical-mounted reader hasn't been a larger focus by hardware developers, especially as smart phones have dealt a fairly devastating blow to the ereader market.

Aside from this sub, where can I read more about this burgeoning technology?

#7  mdp 03-17-2019, 06:06 PM
Quote jbiggley
pseudo-AR reading experience is an exciting possibility
I have used it for probably over 50 hrs in the past two weeks, between text, video and interactive material, and happily: in my case it is a fulfilling reality.

#8  bango 03-29-2019, 08:58 AM
Thought I would chime in - I bought an epson moverio 35bt-e. It has very similar specs to the 300. Mdp's reconstruction pics are extremely accurate when using an inverted colour scheme.

The model I use allows for hdmi in so I can use it a second or even primary monitor for my comp or phone. It is a really cool experience.

Free hand drawing on my surface pro reflected in front of my eyes in real time is quite an experience.

#9  Sidor 04-03-2019, 01:36 PM
Fortunately this is not a limit. Every AR app company has the way to improve.
AR industrial apps are in the progressive phase today and they don't just refer to entertainment, it became useful in such aspects of industrial processes, as the quality control, training of the new-coming pros, repairing or remoting modelling and drone dev of course. So, it has already become a new way to explore the universe and describe it to the people.

#10  mdp 04-03-2019, 03:18 PM
Quote Sidor
AR industrial apps are in the progressive phase
Very possibly there will be soon killer apps for AR that will have users wonder "How could we do without before?". Meanwhile, it is very good to see that current software applications are already usable on AR sets, so there is the benefit of a quasi-seamless continuity in the two worlds of mobile and augmented reality applications.
Also, it is very good that we are starting to see implementations like the Epson Moverio, that combine quality, well thought engineering and affordability (to my research, this product is the first one, and to my experience, it is a success). Without this, technology cannot soar.

  Next »  Last »  (1/3)
Today's Posts | Search this Thread | Login | Register