Precise touch screens thanks to AI

We are probably all familiar with this: if you want to quickly type a message on your smartphone, you sometimes hit the wrong letters on the small keyboard – or on other input buttons in an app. The touch sensors, which detect finger input on the touch screen, have not changed much since they were first released in mobile phones in the mid-2000s. In contrast, the screens of smartphones and tablets are now providing unprecedented visual quality, which is even more evident with each new generation of devices: higher colour fidelity, higher resolution, crisper contrast. A latest-generation iPhone, for example, has a display resolution of 2532x1170 pixels. But the touch sensor it integrates can only detect input with a resolution of around 32x15 pixels – that's almost 80 times lower than the display resolution: "And here we are, wondering why we make so many typing errors on the small keyboard? We think that we should be able to select objects with pixel accuracy through touch, but that's certainly not the case," says Christian Holz, ETH computer science professor from the Sensing, Interaction & Perception Lab (SIPLAB) in an interview in the ETH Computer Science Department's "Spotlights" series.