Ultrasensitive Mesh‐Structured Position‐Sensitive Detectors Enabling Eye Tracking for Human‐Machine Interaction

Abstract

ABSTRACT Eye tracking provides highly efficient, intuitive, and seamless human‐machine interaction by measuring eye movements and revealing user attention and intention. Currently, video‐based eye tracking systems, while achieving sub‐degree accuracy, suffer from high power consumption due to data acquisition and processing of redundant pixels. Here, we present an energy‐efficient eye‐tracking system employing a position‐sensitive detector (PSD) with a graphene photoconductive mesh, which operates with only four readout signals, reducing data volume by over three orders of magnitude compared to video‐based systems, while achieving superior accuracy. With the synergistic effects of lateral photoelectric and interfacial gating, the mesh‐structured PSD operates under eye‐safe ultra‐weak light (as low as 10 pW) without a detection dead zone. Leveraging the real‐time, precise tracking capability of the PSD, the eye‐tracking system determines gaze orientation by tracking the reflected trajectories of light beams from the cornea, achieving a 1 kHz tracking frequency and < 0.1° angular accuracy. Human‐machine interaction applications such as eye‐controlled typing and a Gluttonous Snake game are demonstrated using the PSD‐enabled eye tracker. The PSD‐based eye tracking holds significant promise for the application of human‐machine interaction in miniaturized systems.