Ultrahigh-speed chromatically band-limited illumination profilometry

Single-shot fringe projection profilometry (SS-FPP) has been extensively applied to the study of rapid three-dimensional (3D) dynamics in physics, engineering, and biology. Despite these advancements, the imaging capability of time-resolved SS-FPP is still limited by the flexibility and speed of both pattern projection and image acquisition, as well as by the duration of the observation time window. Here, we overcome these constraints by developing chromatically band-limited illumination profilometry (C-BLIP). On the illumination side, C-BLIP projects programmable grayscale fringes at ultrahigh speed by synergizing a digital micromirror device with a user-selectable encoding region of interest and a custom-designed projection lens for chromatically band-limited illumination with incoherent light sources. On the detection side, C-BLIP acquires spatially multiplexed color fringe images, followed by 3D image reconstruction. Using C-BLIP, we demonstrated color 3D imaging of a turbofan blade-projectile collision at 25 thousand frames per second (kfps), as well as intensity 3D imaging of maple samara's fall aerodynamics at 75 kfps and ultrasound encryption/recovery at 150 kfps. These results highlight C-BLIP's promise for continuous-streaming, ultrahigh-speed 3D metrology in industrial inspection, bionics, and data security.