Most of today’s smartphone manufacturers think of only a couple of things when prepping a display. The brightness and viewing angles are probably the main focus, size seems to matter a whole lot lately, as well as color reproduction and pixel density.

Those are all very important things for day-to-day smartphone users. But how about thinking a little bit outside the box and really innovating for a change? Well, fear not, ladies and gents, because there are two companies out there that seem to be thinking things one step ahead of everybody else.

NTT DoCoMo, the most important mobile operator in Japan, and Fujitsu, the world’s third-largest IT services provider, have joined forces to work on the first ever smartphone with a double-sided transparent OLED touchscreen display.

The first prototype was showcased at the Expo Comm Wireless Japan International Exhibition and Conference, and, while it clearly looks like something that needs some serious work, it tickles our imaginations big time.

Fujitsu and NTT DoCoMo’s concept practically comes with two touchscreens, which can be used at the same time to provide a more intuitive user experience. You can, of course, use either display independently or both of them simultaneously for multi-tasking.  Aside from the fact that it looks very cool, the still unnamed prototype is meant to add quite a bit of functionality to future smartphones.

Diginfo.tv and Tokyotek.com have been kind enough to upload YouTube video clips showing a couple of complicated gestures that can’t be currently performed on smartphones, but will be possible once (or if) commercial versions of the prototype will become available. On the other hand, you can clearly notice some of the gadget’s weak points, which should definitely be solved before entering production.

The current prototype sports a very small 2.4-inch display with a modest QVGA resolution (320 x 240 pixels). If a phone were to ever be released with a double-sided transparent screen, it would clearly need a larger and more capable panel. However, that’s probably a hurdle that NTT DoCoMo and Fujitsu will be able to overcome with ease. The brightness issue seems to be the most difficult one, as see-through pretty much equals poor image quality under difficult lighting conditions.

One way to go about this issue would be to place a dark object behind the screen of a future phone, but that wouldn’t be a very convenient solution, now would it? The device is still many months away from its commercial debut, so there’s still plenty of time for Fujitsu and NTT DoCoMo to iron out the the issues of the prototype.

Check out the clips below to see what all the fuss is about and tell us if you’re excited about this new concept.