dual finger selection

microsoft research

Dual-finger selection on a multi-touch tabletop display. The user manipulates the pointer with the right hand while adjusting the control-display ratio with the left.

The size of human fingers and the lack of sensing precision can make precise touch screen interactions difficult. We created a set of five techniques, called Dual Finger Selections, which leverage the recent development of multi-touch sensitive displays to help users select very small targets. These techniques facilitate pixel-accurate targeting by adjusting the control-display ratio with a secondary finger while the primary finger controls the movement of the cursor. We also contribute a “clicking” technique, called SimPress, which reduces motion errors during clicking and allows us to simulate a hover state on devices unable to sense proximity. We implemented our techniques on a multi-touch tabletop prototype that offers computer vision- based tracking. In our formal user study, we tested the performance of our three most promising techniques (Stretch, X-Menu, and Slider) against our baseline (Offset), on four target sizes and three input noise levels. All three chosen techniques outperformed the control technique in terms of error rate reduction and were preferred by our participants, with Stretch being the overall performance and preference winner.

Benko, H., Wilson, A., and Baudisch, P. Precise Selection Techniques for Multi-Touch Screens. To appear in Proceedings of CHI 2006, Montreal, Canada, April 2006. PDF |  WMV --> download from publications page

In collaboration with Hrvoje Benko (principal investigator) and Andy Wilson