Simultaneous ToF/FMCW LiDAR Using a Dual‐Mode Light Source in a Single Architecture

Light detection and ranging (LiDAR) systems are increasingly required to provide long‐range operation, high axial resolution, and velocity estimation within a single platform. However, conventional time‐of‐flight (ToF) and frequency‐modulated continuous‐wave (FMCW) methods demand a high electrical bandwidth to satisfy these requirements simultaneously. Here, we present a simultaneous ToF/FMCW LiDAR enabled by a dual‐mode light source that alternately generates nanosecond pulses and FMCW waveforms through synchronized optical‐intensity and frequency‐modulation. This single‐architecture design enables concurrent acquisition of time‐domain ToF and spectral‐domain FMCW ranging without additional optical paths or auxiliary light sources. Under bandwidth‐limited conditions, ToF measurement maintained absolute distance accuracy despite a loss of resolution, whereas the FMCW measurement preserved high axial resolution but experienced aliasing due to subsampling. By integrating these complementary datasets through a reconstruction algorithm, the system achieves high‐resolution short‐range performance together with alias‐free long‐range detection. Moreover, Doppler analysis of the FMCW interferograms verified accurate velocity estimation within the Nyquist limit. These results demonstrate that a dual‐mode light source can unify ToF and FMCW ranging in a compact single architecture, overcoming electrical bandwidth constraints while enabling simultaneous distance and velocity measurements.