Comparative Analysis of Phase Unwrapping in PSP Using Depth Images

The main techniques in the optical measurement are Fourier Transform Profilometry (FTP), Wavelet Transform Profilometry (WTP) and Phase-Shifting Profilometry (PSP) Among them, PSP algorithms are the most widely used in optical measurements due to its numerous advantages as are point-by-point measurement less sensitive to variations in reflectivity surface (which makes it easier the measurement of complex objects with strong variations in texture), and less sensitivity to ambient light. This paper describes a novel approach to check the error in optical measurements, specifically PSP using firstly a simulation with depth images with all stages: pre-processing, phase wrapping and phase unwrapping. Finally, the results are checked with real objects. This research uses three-step and four-step method to establish a comparison. Moreover, the most common phase unwrapping algorithms are analyzed (The most important part to obtain tridimensional information of an object) applied to PSP.