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Imaging and Wave Optics

Department 4.2


The core tasks of Department 4.2:

Measuring the form of optically smooth surfaces
Optical methods (interferometry, deflectometry) are used to measure the form of optically smooth surfaces with uncertainties from a few ten nanometers down to single nanometers, depending on the surface form. Applications range from flat surfaces, spheres, aspheres to freeform surfaces.

Characterizing optical components and optical wavefronts
Parameters of optical components (refractive index of glasses and liquids, optical rotation of quartz control plates, modulation transfer function of lenses, etc.) are measured with high accuracy. In addition, optical wavefront sensors are characterized and calibrated.

Measuring the size and shape of microscopic surface structures
The size and shape of micro- and nanostructures on surfaces are measured. The dimensions of the structures may range from a few 100 micrometers to below 100 nanometers. Both light microscopic and non-imaging optical methods (scatterometry, diffractometry, ellipsometry) from the visible to the deep ultraviolet spectral range are used for this purpose.

Measuring the lattice parameter of crystalline silicon
In a basic experiment, the lattice parameter of high-purity and nearly perfect silicon crystals are measured with the highest possible accuracy. For this purpose, a combination of optical and X-ray interferometer is being developed and used.

In all fields of activity, we conduct basic research, develop measurement methods and perform measurements and calibrations for industry and science. Research projects are often carried out in cooperation with industry.

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