Mid-Air Ultrasound Haptics

A non-contact haptic technology that uses phased arrays of ultrasonic transducers to focus acoustic radiation pressure onto a user's skin, producing tactile sensations in mid-air without any worn or held device. By modulating the intensity, focal-point location, and trajectory of the ultrasound beam (for example via spatio-temporal modulation), the system can render points, lines, textures, and shapes that are perceived as touches, strokes, or vibrations. For accessibility, mid-air ultrasound haptics is relevant as a hygienic, device-free output modality that can deliver spatially resolved tactile information to blind and low-vision users without occupying their hands with a controller or wearable.