The invention discloses a three-dimensional planta pedis scanning device and a scanning method based on a single-camera four-step
grating phase shift method. A
sinusoidal grating, a
servo motor and agear, which are linked, are arranged on a transverse supporting plate on a side plate of a box body; a
laser light source, which is adaptive to the
sinusoidal grating, is arranged at the bottom of thebox body; an image reflective mirror surface is arranged in the middle of the box body; a
single camera is arranged at the other end of the box body; the
sinusoidal grating is irradiated on planta pedis of a
human body; a physical
grating, under the control of the
servo motor, is moved by a certain distance; four distorted gratings that a
phase difference is [phi] / 2 are formed on the surface of the planta pedis; by virtue of an industrial camera, four distorted
grating images are acquired; and the gratings are subjected to
phase analysis, so that three-dimensional
data information of the planta pedis is obtained. According to the scanning device and the scanning method provided by the invention, the grating images are acquired by virtue of the high-precision industrial camera, and with the adoption of the four-step phase shift method,
random noise can be filtered out and precision can be improved; and the
system, which just uses one camera, can reduce
system cost and implement high-precision scanning.