Microsoft Lucid Touch

Touchscreen problem would be your fingers getting in the way of small screen. That is why Microsoft bring the concept of backside touchscreen which allow user to control the device from behind but still being able to see their fingers. Microsoft has shown off Microsoft LucidTouch prototype at the TechFest fair, an internal event highlighting key tech from the company’s 800 research and development staff.

According to the company, the key to making this usable is what it calls pseudo-transparency: by overlaying an image of the user's hands onto the screen, the illusion of the mobile device itself being semitransparent is created. This pseudo-transparency allows users to accurately acquire targets while not occluding the screen with their fingers and hand.

According to Microsoft in initial studies, results suggest that many users found touching on the back to be preferable to touching on the front, due to reduced occlusion, higher precision, and the ability to make multi-finger input.

So with Microsoft Lucid Touch you'll have less finger prints in your screen, or can I say reduce them.