a chromatic confocal technique and apparatus for the rapid three - dimensional measurement of an object shape , particularly of a tooth in a patient &# 39 ; s jaw , using an array of polychromatic point light sources , a planar detector matrix , a beam splitter for lateral spectral separation , and an objective for illuminating and recording the object . spectral defined reference light bundles are generated , injected into the detection beam path via a reference beam path and , following spectral splitting , are focused on the detector matrix as reference image points , wherein laterally shifted sub - matrices are numerically defined on the detector matrix for spectral analysis of the object light , which sub - matrices are implemented as spectral cells for three - dimensional measurement of the shape of the object .