The CWL is based on the principle of chromatic distance measurement. White-light from a high-performance LED is focused on the surface by a measuring head with a strongly wavelength-dependent focal length. The spectrum of the light scattered on the surface generates a peak in the spectrometer.

The wavelength of this peak is used to determine the height on the sample. The sensor works on transparent, highly reflective or even matt black surfaces. It is extremely fast and has virtually no edge effects.

• non-contact, non-destructive measurement
• very high resolution possible due to small spot,
  low-maintenance LED light source
• suited for use in difficult ambient conditions
• coaxial measurement, no edge effects
• small, wear-free sensor without moveable parts

• quality checks in front-end and back-end fabrication of
  semiconductors (e.g. wafer, die, packages)
• R&D and quality control in micro systems engineering
  (e.g. MEMS, inkjet print heads)
• R&D and quality control in medical technology
  (e.g. stents, catheters, prothesises)
• quality checks in the automotive industry
  (e.g. interior, cylinders, shafts)
• quality checks  of circuit boards, injection moulding (micro-)parts,
  optical components (e.g. lenses)
• profile and 3D-measurements on heavily structured surfaces
  (e.g. tools, rollers, components)