Feb 12, 2023
Using ultrasound to mimic the feel of pressing a button on a glass plate
Posted by Saúl Morales Rodriguéz in category: mobile phones
A pair of engineers at Delft University of Technology, working with a colleague at Aix-Marseille University, reports that applying ultrasound to the surface of a glass plate can mimic the feel of pressed button. Laurence Willemet, Michaël Wiertlewski and Jocelyn Monnoyer have published a paper in Journal of The Royal Society Interface describing the device they built to test the idea of using ultrasound as a haptic screen enhancer.
Currently, users pressing buttons on their smart phone screens do not receive much in the way of physical feedback—phone engineers would like to change that. In this new effort, the researchers looked into the idea of using ultrasound on a glass plate to mimic the sensations of pushing a physical button.
The researchers created the device by merging two modules. One used blue and red lights to optically track the movement of an approaching finger. The other monitored and responded to contact. Together, the modules controlled piezo actuators that generated ultrasound at a frequency of 28.85 kHz. The device was affixed to a glass plate, which in turn was held in place by an aluminum frame. When in use, the actuators were driven by a ±200 V carrier signal.