Simplified Phase Shifting Moiré Interferometer Using a Computer Generated Grid Pattern

A simplified phase-shifting moiré interferometer for generating moiré fringes from projected linear gratings and computer generated grid patterns without using a low-pass filter is presented. In particular, it is demonstrated that moiré fringes can be successfully obtained even when there is no clear frequency separation between the moiré fringe and the grid pattern. It is also pointed out that our proposed method produces fewer phase jumps than conventional phase-measuring profilometry, enabling us to realize more robust phase unwrapping.