Determining the Target Point of the Mid-Air Pinch Gesture

Pinching is a common gesture primarily used for zooming on mobile devices, and previous studies considered utilizing it as a mid-air gesture in AR/VR. As opposed to touch screens, there is no physical contact point between the display and the fingers in mid-air pinching, which means the positional relationship between the target point for zooming and the users' finger movement in mid-air pinching could be different from that of touch screens. In this study, we investigated the relationship in mid-air pinching to estimate the target point from the hand posture, and found that the point was significantly off towards the thumb and away from the index finger (approximately 7% offset). This finding contributes to a more accurate mid-air zooming.