Effect of Frequency Domain Filtering on Fourier Transform Based Phase Extraction

¹ Department of Physics, Shri Shivaji Science and Arts College Chikhli, Dist. Buldhana, Maharashtra, India
² Department of Physics, Institute of Science Nagpur, Maharashtra, India

^* Corresponding author: This email address is being protected from spambots. You need JavaScript enabled to view it.

Published online: 26 June 2026

Abstract

Phase extraction from single interference fringe pattern is an essential step in quantitative interferometry measurements particularly in single shot analysis. Fringe pattern obtained from an interferometer often contain noise due to environmental disturbances and imaging limitations which can affect accuracy of phase retrieval. In this work, Fourier transform method is employed for phase extraction from single image of fringe pattern. This method is applied on unfiltered and filtered interference fringe pattern obtained using Michelson’s interferometer without any external deformation. The extracted phase expected to show linear variations. The quality of extracted phase is measured using phase linearity error and root mean square (RMS) of phase noise for filtered and unfiltered fringe patterns. The RMS phase error and maximum deviation decreases for the filtered interference pattern as compared to unfiltered pattern. These results confirm that prior filtering of fringe pattern before applying the Fourier transform method significantly improves the phase quality, accuracy and reliability.