Purposefully induced axial chromatic aberration is the core of the chromatic confocal metrology technique. Through the resulting generation of separated focal planes for each wavelength of a broadband light source a measurement volume is created and a three-dimensional reconstruction of the topography of technical and biomedical surfaces and layers can be performed. Based on the chromatic confocal metrology technique various metrology sensors and measurement systems have been developed, with high axial and lateral resolution, accuracy and precision. For a significant increase in measurement points, that can be measured simultaneously and the resulting reduction in measurement time, a chromatic confocal method utilizing a micro-lens array in combination with a improved spectral peak detection, has been developed. Through a single image acquisition, the object topography can be measured for multiple points simultaneously and therefore mitigating the need for axial as well as lateral scanning of the object. For this reason in-situ applications have become a viable domain. First preliminary results of testing a laboratory setup of the proposed system design are presented.
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