The chromatic-confocal measurement principle
Chromatic confocal method for optical measurement technology for measuring distance and thickness has been established as one of the mature methods available to industry and research. Incident white light is imaged through a chromatic lens to yield a continuum of monochromatic light along the z-axis, thereby “color coding” the optical axis. When an object is present in this color field, a single wavelength is fixed to its surface and then reflected back to the optical system. The backscattered beam passes through a filtering pinhole and is then acquired by a spectrometer. The beam’s specific wavelength is calculated to precisely determine the position of the surface in the measurement field. Chromatic confocal technology allows reliable, accurate and reproducible dimensional measurements with high resolution.
Find out more about the strengths and limitations of the different and common surface measurement methods in the technology comparison, regarding vertical and lateral resolution, application sweet spots on smooth surfaces or roughness measurement, with or w/o stitching.
- White-light interferometry
- Confocal microscopy
- Focus variation
- Chromatic confocal sensors
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Micro Profiler
Micro.View systems are optimized for ultra-high-resolution measurements in the sub-nanometer range. With focused optics and high vertical resolution they enable detailed analysis of microstructures, surface finish and material distribution where even the smallest deviations matter.
Macro Profiler
Pro.Surf systems enable fast, area-based 3D topography measurements with telecentric optics. They support reliable inspection of flatness, shape, parallelism and step heights across wide fields of view and in-bore features.
Metro.Lab
Metro.Lab is a compact, wide-area surface profiler. It combines high measurement performance with a small footprint—ideal for space or budget conscious applications that still require reliable 3D surface data.
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