Perhaps it's easier to understand if you think of the BT-100 controller as a media player (which runs Android 2.2), and the BT-100 headset as the display device. This means you'll need to be wearing the headset to view and interact with the interface (though the physical interaction happens with the media controller), before you even begin to playback any content. This is obviously because the controller doesn't have an LCD display, thus requiring you to wear the glasses. This saves design cost of the controller, but forces you to wear the headset even if you just want to power it up to check settings and content stored on the device.
Running the stock Android user interface probably doesn't make much sense here, so like all media players, the BT-100 sports its own skin. Smack in the center is a carousel menu that houses your apps, which are represented by large icons. On the right are shortcut links that bring you to the internet browser (usable with a stable Wi-Fi connection), a list of installed apps, or the Android home screen. You can of course put app shortcuts on the home screen, but with the Epson GUI, we don't see a need to do so.
The main level of the carousel contains the Browser, Gallery (for photos and videos), Music, Settings, SEViewer (for accessing the file system), and Help apps. There are more 'pockets' should you wish to drop other apps into the carousel. There is a total of five carousels, and you can go to each of them via the five dots on the left of the screen. Epson has also retained the notification bar at the top of the screen, which you can pull it down to see any notifications (such as an OS update).
Regarding navigation, we found that the trackpad and the d-pad received roughly equal amount of usage. To launch an app, it's easier to use the trackpad: just move the cursor onto it, and tap it. But for maneuvers like scrolling the carousel or a list, the directional keys are more handy. And let's not forget about the Home, Menu, and Back buttons on the controller.
* GUI images above are courtesy of Epson.
Running on the Android platform means that in theory, you can download and install Android apps on the BT-100. However, the BT-100 doesn’t come with the Google Play Store. So, to get apps, you can either download them via the browser, or through third-party app stores, such as the Amazon Appstore or SlideME). Alternatively, if you’ve the APK files, you can sideload them using a microSD card. To get files onto the microSD card, you can either copy them directly using a card reader, or insert the card into the controller, and then connect it to a computer via the controller’s micro USB port.
While we did need a bit of time to get used to the trackpad, we played Angry Birds Seasons for a good hour and enjoyed it. Watching streaming video from Netflix via Wi-Fi also proved to be a success. Finally, we can watch movies on the bed, without worrying about the phone dropping onto our face when we doze off.
The BT-100 also has a browser for surfing the Web and it supports Flash 11. The virtual keyboard works fine for the most part, though it’s troublesome to enter a long URL. Thankfully, you can create bookmarks for sites that you frequently visit.
Natively, the BT-100 only supports MPEG-4 (H.264), AAC, and MP3 AV formats. In most cases, files with a .MP4 extension will playback fine on the BT-100. But what if you’ve files that use other multimedia container formats, such as AVI or MKV? Well, the pre-installed Gallery app will not even recognize them, much less play them. To get around that, you can try using another media player. In our case, we got the AVI and MKV files to play using an app called RockPlayer. But know that since hardware decoding for these files is out of the question, the playback is done via the app’s own software decoder. As a result, performance can be a mixed bag. For example, we had a couple of 1080p MKV files that were just too demanding that we encountered lots of stutters during playback, effectively making them unwatchable.
An HTPS TFT LCD panel (along with a projection lens) is mounted in each arm, and the image reaches your eye after going through some internal reflections. A half-mirror layer (in other words, it’s translucent) at the end serves two purposes: it directs the image to the pupil, and allows external light through the lens. The latter is what enables you to see your surroundings through the lenses even when the screen is turned on. The LCD panels have a qHD resolution - that is, 960 x 540 pixels. Given that the panel is just millimeters away from your eyes, cramming more pixels on the panel will have a positive impact on your movie viewing experience. In other words, a pair of 720p panels would have been better.
Image size-wise, it really depends on where you place your point of view. Imagine you fix the point of view on a wall. The perceived size gets bigger as you increase the distance between you and the wall. Epson claims a 40-inch screen size at 2.5m away, 80-inch at 5m, and 320-inch at 20m. In reality though, these claims don’t really matter, since it’s impractical to fix a viewpoint for a long period of time, especially when you’re moving about. Even if you're seated, it'd take a lot of effort to not move your head in a two-hour movie. As such, you don't quite get the large screen enjoyment as it's touted. What you get from actual usage is a decent sized 'screen' that feels pretty close to your eyes and it moves with you wherever you are, while allowing you a certain degree of viewing your surroundings.
Image quality-wise, we’ll rate it as decent, but not spectacular. For the most part, videos looked sharp. Brightness is good too, but due to the translucent characteristic, details can be hard to make out if you’re out on the street on a sunny day. The headset comes with a lens shade, and we recommend keeping it on, even when you’re indoors, to get the best video experience. Aided by Dolby Mobile technology, surround sound (virtual, of course) was somewhat convincing. If you listen to music, there’s a slew of equalizer modes available. If you don't mind carrying another item, overall audio quality can be enhanced further by using your own choice of earphones.
The BT-100 plays 3D video content too, but is limited to side-by-side 3D content. You also need to press the 2D/3D button on the controller for the headset to display the 3D content correctly. In our experience, the 3D effect was present, but it could certainly do with more depth. Credit to Epson, crosstalk was few and far between. When the movie has ended, you’d need to press the 2D/3D button again to get out of 3D mode, since the user interface isn’t in 3D.