Adding tactile reaction to hologram

In this paper, a hologram with tactile reactions is presented. The developed system consists of three components; a holographic display, a hand tracker, and a tactile display. The tactile display, which is our original device, produces force on user's bare hand without any contact by using radiation pressure of airborne ultrasound. It adds the sense of touch to optical images floating in mid-air. In order to represent the feeling of impact, some improvements are added to the tactile display. As a result, the tactile display has an ability to produce up to 4.8 gf without air flow.