Remotely displaying cooling sensation via ultrasound-driven air flow

A midair haptic display that provides a cooling sensation is developed in this study. Although a noncontact heat display using infrared rays has been reported, such an infrared display cannot cool the skin surface. In this study, we generate and control a straight, thin, long, air flow driven by an ultrasound-phased array and transport cold air to a localized spot on the users' skin. Since the air flow position and direction is electronically steerable, the display area can be controlled freely. A prototype of the proposed display was developed and the cooling performance was evaluated. We confirm that a small cool spot is created and shifted on a user's forearm based on our observations of the temporal changes in the skin temperature distribution using thermography.