Fingerprint scanners are widely used in security applications. In this work, we demonstrate that capacitive fingerprint scanners can also serve as universal communication devices. In this demonstration, we show that a reliable data transmission channel can be established between a wearable device and the fingerprint scanner, using the human body as the medium. We also envision several promising applications that arise from this new opportunity.

As assisted and autonomous driving systems become more prevalent, the need for accurate interpretation of road traffic signs is critical for driving safety and functionality. Current camera-based recognition methods face challenges due to the variability of traffic signs and environmental conditions, leading to potential inaccuracies. To address this, we propose LiDARMarker, a type of machine-readable traffic sign using infrared materials, making it invisible to human drivers but detectable by LiDAR-equipped vehicles. This paper introduces the design, fabrication, and efficient decoding methods of LiDARMarker. LiDARMarker is tailored to the emerging capabilities and needs of modern vehicles, enhancing their ability and accuracy in traffic sign recognition while avoiding interference with human drivers. Through the proposal of LiDARMarker, we aim to inspire the rethinking of the design of traffic sign systems in the context of modern vehicles.