Choosing the Optimal Parameters of the Gaussian Filter for Obtaining the Surface Relief Components

It is known that for the determination of mechanical, corrosive and tribological parameters, such terms as "roughness" and "waviness" are often used. Filtering in the frequency domain is used to extract these components from the total relief. In this paper, we propose an approach for determining the optimum value of the cut-off frequency for 2D Gaussian filter, for our method of retrieving the surface relief by three-step phase-shifting interferometry with an arbitrary phase shift of the reference beam.