%0 Generic
%A Trittler, Stefan
%D 2007
%F heidok:7475
%K Frequenzschätzung , Weisslichtinterferometrie , MehrwellenlängeninterferometrieFrequency Estimation , White-Light Interferometry , Multiple Wavelength Interferometry
%R 10.11588/heidok.00007475
%T Processing of Interferometric Data
%U https://archiv.ub.uni-heidelberg.de/volltextserver/7475/
%X In this thesis, fast and highly accurate interferometric metrology systems for both smooth and rough surfaces are presented. First, high-speed algorithms for white-light interferometry (WLI) and line scanning WLI are developed and their performance is compared. For large height differences, multiple wavelength interferometry is significantly faster, though, as in this approach the number of frames required for a surface estimate does not increase with surface height range. A system based on a tunable diode laser is discussed in detail, and new sampling schemes and estimation algorithms for the device are derived. An approximation to the theoretically optimal sampling pattern is given and a corresponding fast estimation algorithm is presented. As a building block for that algorithm, accurate and fast phase and frequency estimation from a low number of samples is discussed, and a new approach based on an interpolated FFT is presented. The influence of laser speckle on rough surfaces is investigated. A robust, adaptive filtering algorithm is developed. It takes spatial relationships into account — without imposing strong smoothness constraints — and uses additional knowledge on the signal from the raw data to improve performance significantly, especially on rough surfaces.