Flexible photonic contactless human-machine interface based on visible-blind near-infrared organic photodetectors.

Contactless human-machine interfaces (C-HMIs) are revolutionizing artificial intelligence (AI)-driven domains, yet face application limitations due to narrow sensing ranges, environmental fragility, and structural rigidity. To address these obstacles, we developed a flexible photonic C-HMI (Flex-PCI) using flexible visible-blind near-infrared organic photodetectors. In addition to its unprecedented performance across key metrics, including broad detection range (0.5-60.0 cm), high spatial resolution (∼10.0 µm), and fast response speed (1.6 µs), our Flex-PCI could precisely track finger kinematics and human physiological information, including position, velocity, trajectory, heart rate, and respiratory rate. Additionally, the Flex-PCI could stably operate under diverse conditions, such as various temperatures, humidities, ambient light intensities, bending states, and even underwater, addressing the reliability gap in dynamic applications. These combined, unparalleled characteristics have been demonstrated through a high-dimensional security system synergistically featuring tracking of finger kinematics and human physiological information in aerial and aquatic environments. This breakthrough technology opens up numerous possibilities for contactless interactions across diverse AI-powered scenarios, from security systems, social media, and AR/VR, to personal interactions with gaming and entertainment, significantly enhancing the quality of the user experience.