A 3D scanner for recording the 3D topography of an object, the 3D scanner includes an illumination unit configured for providing probe light for illuminating the object, where the probe light includes a pattern of light rays; an image sensor for acquiring one or more 2D images of light rays returning from the illuminated object; an optical system including an optical element arranged such that the patterned probe light passes through it when propagating towards the object from the illumination unit along an optical path; and a device for changing the configuration of the optical system between a first and a second configuration, where the change in configuration comprises a change in orientation of the optical element between a first orientation and a second orientation relative to the optical path of the probe light.