Arrangement and method for increasing the measurement accuracy in the three-dimensional measurement of objects

An arrangement for three-dimensional measurement of objects comprising:

• a planar substrate for placing thereon at least one object to be measured;
• an emitting device for emitting light beams in the direction of the at least one object;
• a receiving device for detecting the light beams reflected from the at least one object and the substrate;
• and
• a determining device for determining 3D data on the basis of time-of-flight measurements and/or triangulation of the emitted and reflected light beams and for determining the dimensions of the outer shell of the at least one object from the determined 3D data;
• a transparent plate having a predetermined thickness for placement between the at least one object and the substrate, the thickness being higher than a measurement inaccuracy range forming on the substrate, the thickness being in a range between 1 and 50 millimeters
• wherein the determining device corrects the determined 3D data or the determined dimensions of the outer shell of the at least one object by the thickness of the transparent plate (8), in that
• the determining device first determines 3D data of the at least one object to be measured together with the transparent plate and the substrate, which serves as reference surface;
• wherein
• the determining device determines a virtual, planar separation plane running parallel to the reference surface and spaced apart from the latter by at least the thickness;
• the determining device separates and eliminates the determined 3D data between the separation plane and the reference surface from the remaining determined 3D data;
• and
• the determining device determines the dimensions of the outer shell of the at least one object on the basis of the remaining 3D data.