Prof. Masatoshi Ishikawa and Dr. Takashi Komuro of Tokyo University developed so-called "vision-based Input Interface". The device captures movement of five fingers by embedded camera and translates it to command. To catch finger movement, the device adopted 154 fps high-speed camera. Usually two lenses are used to detect 3D movement but customized softwares enables camera to detect them with only one lens.
Unlike any devices we have seen before, it doesn't need surrounding optical sensors or fingertip markings for motion capturing. This is amazing breakthrough technology. We saw how cool Tom Cruise controling the computer by just moving his fingertips in the air in Minority Report.
Although it looks cool, I think this input technology is not practical if it embedded on mobile devices. You have to practice for some time on the virtual keyboard. Even if you're skillful enough to use, it will be a different story if you're texting while walking on the street.
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