3D stylus using echolocation

At a mobile congress in Barcelona, ​​Texas Instruments showed a prototype stylus that allows you to draw 3D objects. The most interesting thing about this device is how accurately its coordinates are determined in space. To do this, use echolocation at high frequencies (ultrasound). Microphones are installed in each of the four corners of the tablet, which record the reflected signal.

Of course, the stylus works fine and in 2D-mode, that is, as an ordinary stylus, and while it is not limited by the resolution of the touchscreen. Actually, he doesn’t need a touch-sensitive screen at all, but he can draw even on ordinary glass, the main thing is that there are microphones around.