Real-time wide-field spectral-scanning FMCW coherent 3D imaging and velocimetry

We present a real-time spectral-scanning frequency-modulated continuous wave (FMCW) 3D imaging and velocimetry system that can produce 3D depth maps at 33 Hz, with 48 degrees x 68 degrees field of view (FOV) and 32.8-cm depth range. Each depth map consists of 507 x 500 pixels, with 0.095 degrees x 0.14 degrees angular resolution and 2.82-mm depth resolution. The system employs a grating for beam steering and a telescope for angular FOV magnification. Quantitative depth, reflectivity, and axial velocity measurements of a static 3D printed depth variation target and amoving robotic arm are demonstrated. (C) 2022 Optica Publishing Group