1. An imaging apparatus for performing intraoral scans, comprising:a light source to provide light;
an optical system comprising a plurality of lenses disposed along an optical path of the light, wherein the optical system comprises a non-flat focal surface, and wherein the optical system comprises focusing optics to perform focusing of the light onto the non-flat focal surface and to direct the light toward a three dimensional object to be imaged in an oral cavity;
a translation mechanism to adjust a location of at least one lens of the plurality of lenses to thereby adjust a focusing setting of the optical system and displace the non-flat focal surface along an imaging axis defined by the optical path, wherein the at least one lens is a lens of the focusing optics, and wherein at least one of a shape or a magnification of the non-flat focal surface changes with changes in the focusing setting; and
a detector to measure intensities of returning light that is reflected off of the three dimensional object and directed back through the focusing optics, wherein the intensities of the returning light are to be measured for a plurality of locations of the at least one lens for determination of positions on the imaging axis of a plurality of points of the three dimensional object, wherein detected positions of one or more of the plurality of points are to be adjusted to compensate for the non-flat focal surface using one or more compensation models that provide different adjustments for different focusing settings of the optical system.