Synchronization‐Free Single‐Photon 3D Imaging

Abstract 3D imaging using single‐photon time‐of‐flight (ToF) detection has emerged as a potential solution for sensing in challenging scenarios. However, most schemes require strict synchronization between the illuminating light transmitter and the detector, which greatly limits their practicality and flexibility. Here, a synchronization‐free single‐photon 3D imaging scheme that exploits only binary‐encoded illumination light and a photon time‐stamping high‐speed detection system are proposed. The correlation between the arrival times of photons detected by individual pixels is utilized to achieve clock synchronization, and further calculate the ToF differences of photons detected by different pixels to extract the depth information of the imaging target. This scheme can adapt to conditions with signals as weak as photons per pulse per pixel. This work provides a simple, flexible method for realizing 3D imaging in long‐range and high‐loss scenes, paving the way for future applications in large‐scale, high‐complexity real‐world scenarios.