Fourier optics modelling of coherence scanning interferometers

de Groot, Peter J.; Colonna de Lega, Xavier; Su, Rong; Coupland, Jeremy; Leach, Richard K.

Abstract

We 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.

Citation

de Groot, P. J., Colonna de Lega, X., Su, R., Coupland, J., & Leach, R. K. (2021). Fourier optics modelling of coherence scanning interferometers. In SPIE OPTICAL ENGINEERING + APPLICATIONS. https://doi.org/10.1117/12.2595668

• Presentation Conference Type: Edited Proceedings
• Conference Name: Applied Optical Metrology IV
• Start Date: Aug 1, 2021
• End Date: Aug 5, 2021
• Acceptance Date: Aug 1, 2021
• Online Publication Date: Aug 5, 2021
• Publication Date: Aug 5, 2021
• Deposit Date: Aug 11, 2021
• Publicly Available Date: Aug 11, 2021
• Publisher: Society of Photo-optical Instrumentation Engineers
• Volume: 11817
• Book Title: SPIE OPTICAL ENGINEERING + APPLICATIONS
• ISBN: 9781510644724
• DOI: https://doi.org/10.1117/12.2595668
• Public URL: https://nottingham-repository.worktribe.com/output/6012136
• Publisher URL: https://www.spiedigitallibrary.org/conference-proceedings-of-spie/11817/118170M/Fourier-optics-modelling-of-coherence-scanning-interferometers/10.1117/12.2595668.short?SSO=1
• Additional Information: Copyright (2021) Society of Photo‑Optical Instrumentation Engineers (SPIE). One print or electronic copy may be made for personal use only. Systematic reproduction and distribution, duplication of any material in this publication for a fee or for commercial purposes, and modification of the contents of the publication are prohibited.; ; Peter de Groot, Xavier Colonna de Lega, Rong Su, Jeremy Coupland,; Richard Leach, "Fourier optics modelling of coherence scanning; interferometers," Proc. SPIE 11817, Applied Optical Metrology IV, 118170M (5 August 2021). DOI: https://doi.org/10.1117/12.2595668