From ATMs to GPS devices to smartphones, touch screens are now ubiquitous. As vast quantities of information are delivered literally to our fingertips, we are increasingly interacting with the digital, well, digitally. But so far, it’s generally a one-sided exchange: Screens are capable of sensing our touch, but we get no physical feedback. One exception is vibrations, which announce the arrival of text messages and enhance the experience of playing video games, but this barely scratches the surface in terms of possibilities for tactile interaction.
In recent years, though, computer scientists at the University of Tokyo have developed something called the Airborne Ultrasound Tactile Display, which promises to radically expand these possibilities. Producing “touchable holograms,” the system allows users to feel the size, shape and even the texture of objects they see on a screen—for example, a ball bouncing or raindrops falling on their hands—with no special gloves or input devices required. It does this by radiating, in the space above the display, extremely focused ultrasound waves capable of exerting force on but not penetrating skin.
Japan has been at the forefront of this trend. In 2001, researchers at the University of Tsukuba exhibited Feelex, a matrix of controllable rods, covered by a flexible screen, that reshape automatically, providing a tactile topology to complement screen graphics. In 2004, the Nippon Telegraph and Telephone Cyber Communication Laboratory Group invented a system that used targeted airstreams, not ultrasound, to create the sensation of contours.
The future uses of this technology are fascinating to contemplate: We may be able to feel the topography of digital maps or the texture of virtual textiles. Now that we are increasingly viewing images in 3-D, will we one day have the equivalent experience of touching them as well?