PinchLens

Also known as Semi-pinch magnification

Bare-hand pinch selection for tiny, packed objects: starting a pinch opens a magnifying bubble around the fingertips and slows the virtual hand, and closing the pinch picks the target.

How it works

When the thumb and index tips come within 3.5 cm (semi-pinch) near a target, a spherical lens centred on the pinch point magnifies nearby targets in visual and motor space (sizes 4x, distances 3x, from a 1.67 cm area to a 5 cm sphere) and hides targets outside it. At the same time the virtual hand is slowed to half speed (adaptive control-display gain), a small cursor shows the pinch point, and a 1€-style filter steadies the hand. Completing the pinch selects the nearest target; afterwards the magnification ends and the virtual hand drifts back to the real one. In a pick-and-place study (N=12, Meta Quest 2 hand tracking, 0.75–1.5 mm targets, 500–1000 in an 8 cm cube 30 cm away), errors fell from 18.9% with plain pinching to 1.9%, with magnification as the main factor.

Papers

Fengyuan Zhu, Ludwig Sidenmark, Mauricio Sousa, Tovi Grossman (2023). PinchLens: Applying Spatial Magnification and Adaptive Control-Display Gain for Precise Selection in Virtual Reality. IEEE International Symposium on Mixed and Augmented Reality (ISMAR), pp. 1221–1230 doi:10.1109/ISMAR59233.2023.00139