Discussion the effect of non-collimated light path on moire deflectometry based on diffraction theory

摘要

In this paper, the effect of non-collimated light path on moire deflectometry is studied based on scalar diffraction theory. The complex amplitude of non-collimated light path is initially deduced, which shows it has a magnification factor compared with that of the collimated light path. Then, the intensity distribution and fringe equation are obtained, analyzed and discussed under different orders filtering. Based on which, it is found that a series of linear function under non-collimated light without phase object causes the moire fringes to tilt, and the effect of phase object's position on final moire fringe is compared. Finally, the relevant theoretical derivation results are validated by comparing with that of experiment, which proves our theoretical deduction is reasonable. In conclusion, the results could provide some references for expanding the application range of moire deflectometry.