HaloTouch: Using IR Multi-Path Interference to Support Touch Interactions with General Surfaces
Published in Proceedings of the 2025 CHI Conference on Human Factors in Computing Systems (CHI '25), 2025
Recommended citation: Ziyi Xia, Xincheng Huang, Sidney S Fels, and Robert Xiao. 2025. HaloTouch: Using IR Multi-Path Interference to Support Touch Interactions with General Surfaces. In Proceedings of the 2025 CHI Conference on Human Factors in Computing Systems (CHI '25). Association for Computing Machinery, New York, NY, USA, Article 548, 1–17. https://doi.org/10.1145/3706598.3714179
Abstract: Sensing touch on arbitrary surfaces has long been a goal of ubiquitous computing, but often requires instrumenting the surface. Depth camera-based systems have emerged as a promising solution for minimizing instrumentation, but at the cost of high touch-down detection error rates, high touch latency, and high minimum hover distance, limiting them to basic tasks. We developed HaloTouch, a vision-based system which exploits a multipath interference effect from an off-the-shelf time-of-flight depth camera to enable fast, accurate touch interactions on general surfaces. HaloTouch achieves a 99.2% touch-down detection accuracy across various materials, with a motion-to-photon latency of 150 ms. With a brief (20s) user-specific calibration, HaloTouch supports millimeter-accurate hover sensing as well as continuous pressure sensing. We conducted a user study with 12 participants, including a typing task demonstrating text input at 26.3 AWPM. HaloTouch shows promise for more robust, dynamic touch interactions without instrumenting surfaces or adding hardware to users.
Paper: DOWNLOAD PDF
Demo:
Talk: