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Download fileFourier optics modelling of coherence scanning interferometers
conference contribution
posted on 2021-11-09, 14:13 authored by Peter De Groot, Xavier Colonna de Lega, Rong Su, Jeremy CouplandJeremy Coupland, Richard LeachWe propose an instrument model for coherence scanning interferometry using familiar Fourier optics methods, the spectrum of plane waves, and the assumption that the light source spectral bandwidth is the dominant factor in determining fringe contrast as a function of optical path length. The model is straightforward to implement, is computationally efficient, and reveals many of the common error sources related to the optical filtering properties of the imaging system. We quantify the limits of applicability of the model related to the geometrical approximations for conventional Fourier optics, particularly for high numerical apertures, and when using the fringe contrast for determining surface heights. These limitations can be overcome by using a three-dimensional imaging model.
Funding
EMPIR program (20IND07) co-financed by the Participating States and from the European Union’s Horizon 2020 research and innovation program
Revisiting optical scattering with machine learning (SPARKLE)
Engineering and Physical Sciences Research Council
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School
- Mechanical, Electrical and Manufacturing Engineering