Smartphone-based hybrid 3D profilometry with an extended imaging depth range based on binary code and phase-shifting

For the emerging demands of three-dimensional (3D) profile measurement in daily life, a smartphone-based 3D profilometry based on structured light was presented in this paper. To measure 3D profiles within a large depth range, a method combing binary code and phase-shifting was employed. Applying anti-phase complementary binary code patterns successfully overcame the defocusing issue of both the camera and projector. It also helped reduce the influence of objects’ surface reflectivity and the phase unwrapping error. For a depth range of 1100 mm, an average height reconstruction error lower than 2 mm can be achieved with this system.