Abstract: Moiré fringe appears in photos when the stripes with the width similar to the pixel of digital cameras are shot.Considering Moiré effect of digital camera,we select parallel Moiré fringe.With the displacement amplification of parallel Moiré fringes,tiny movement of stripes can be calculated precisely.We expounded its calculating methods in this paper.Experimental results show that a high precision can be guaranteed within 100 m.