A device for acquiring the three-dimensional shape of the surface of an object comprises a lens; deflection means; at least two masks; at least two projection assemblies adapted to emit light beams which, by passing through the masks and the deflection means and by traveling along a channel which passes through the lens, strike the object to be acquired, projecting onto it the mutually offset images of the masks; means for acquiring the images reflected by the object; and means for processing the reflected images. The deflection means are semireflecting and the masks are adapted to project fringe images of the cosinusoidal type through the deflection means.