Two-step phase shifting profilometry based on Lissajous ellipse fitting technique

<sec> Phase shifting profilometry (PSP) is an effective technique to reconstruct the three-dimensional shape of object. In general, PSP needs three or more fringe patterns with phase-shifting accurately known extract phase distribution objects. Therefore, scene and test objects should remain stationary during capturing patterns. However, shifts may be unknown in actual measurement system, especially when measuring moving object, that is, phase-shift error introduced obtaining dynamic scenario, use fewer can realize faster speed suppress shift by this paper, a two-step algorithm proposed based on Lissajous ellipse fitting (LEF). The method uses only two object caused </sec><sec> practical spatiotemporally varying background intensity modulation also significantly affect accuracy extracted LEF, thus error-suppressing methods are reduce non-uniform modulation. order verify effectiveness methods, we analyze compare their performances suppression under different intensities modulations. advantages summarized as follows. 1) mean correction has greater advantage than other vary time. 2) When relevant pixel position number patterns, empirical mode decomposition normalization effectively influence experiment, LEF conducted. Compared traditional which at least successfully extracts suppresses motion Fourier transform (FTP), obtain very accurate retain many details. </sec>