Ultrahaptics uses ultrasound waves to make one feel as if he/she is touching virtual objects and surfaces with bare hands.
It’s creator, a University of Bristol graduate student, claims that it improves upon touch-free interfaces such as Kinect and Leap Motion by reflecting air pressure waves off the hand to create different sensations for each fingertip.
Applications could include interacting with moving objects in virtual reality games, or improving navigation for the visually impaired by projecting the sensation of Braille letters onto fingers in midair.