Circular Lateral Modulation in Airborne Ultrasound Tactile Display

Airborne Ultrasound Tactile Display (AUTD) can present tactile stimulus on the skin, but the generated pressure is too small in many cases to be perceived on the hairy part. In a previous paper, we proposed a lateral modulation (LM) method where the ultrasound focus was reciprocated along the skin surface instead of amplitude modulation (AM). LM provided clear vibrotactile stimuli even on the hairy skin. In this research, we examine a new modulation named LMc where the ultrasound focus follows a circumference on the skin. In this method, the frequency of the pressure received by each skin receptor is constant regardless of the position. The conference participants experience the difference among AM, LM, and LMc.