Researchers at the École Polytechnique Fédérale du Lausanne (EPFL) have developed a technique for giving touchscreens tactile surfaces, so that users have the impression of touching a raised surface. Among the many potential applications, it could be used to make touchscreens more accessible for people with visual impairments.

 

The novel technique, developed by EPFL’s Integrated Actuators Laboratory in Neuchâtel, is targeted at smartphones, tablets, computers, and vending machines.

 

Conventional touch screens rely on visual interaction with the user and lack tactile features. By adding a tactile dimension to touchscreens, the novel technique increases their usability and enhances the user’s experience. It could be used to add emphasis to onscreen text or make video games even more entertaining by adding an additional sensory dimension. For the visually impaired, it could truly open up access to smartphones and other electronic devices.

 

The tactile effect is obtained by using a piezoelectric material that vibrates when an AC voltage is applied to it. Although the amplitude of these mechanical vibrations is very small (around 1 micron), they create an air cushion between the user’s fingertip and the screen, which gives the impression of a raised surface.

 

Image: EPFL