Thin and flexible airborne ultrasound phased array for tactile display

This paper proposes a method to realize a thin and flexible airborne ultrasound tactile display (AUTD). AUTDs generate tactile sensation by utilizing acoustic radiation pressure without wearing devices. The sheet-like device is achieved by developing a thin electrostatic-force-driven ultrasound transducers. In contrast to AUTDs using piezoelectric ceramic transducers, the proposed structure can achieve flexibility and transparency. These unique features will enable new applications of airborne ultrasound tactile display including a portable mid-air tactile display. In addition, the fabrication cost can be reduced, because the transducer array can be fabricated based on the flexible printed circuit technology. In this paper, we fabricated an 8 × 8 phased array prototype and conducted an experiment to confirm whether the device can make a focal point. The experimental result suggested it could make a focal point as we supposed.