Two-dimensional S-transform profilometry with an asymmetry Gaussian window

- 2D S-Transform with an asymmetry Gaussian window is proposed in fringe analysis.
- The theoretical derivation of proposed 2D S-Transform method is given.
- The proposed 2D S-Transform method shows a better performance in 3D surface profilometry.

Two-dimensional S-Transform is an extension of one-dimensional S-Transform. It analyzes the fringe pattern to obtain the useful information from the instantaneous local information in two directions. Due to the application of Gauss Window, time resolution in the time-frequency spectrum is degraded because of the long front taper. In this paper, an asymmetry Gaussian window is introduced in the two-dimensional S-Transform method. With a decreased front taper and an increased back taper for the Gauss window, the proposed two-dimensional S-Transform method can reconstruct the measured object more accurately.