Formulation of moiré fringes based on spatial averaging

The use of moiré technique in measurements often involves locating the position of moiré fringe and in some cases determining its profile. Due to intensity fluctuation in the fringe pattern, these measurements are accompanied by some errors. It is possible to define a smoothed version of the original fringe pattern and then formulate the related subject in accordance with the characteristics of this new pattern. This procedure reduces these types of errors and gives a well-defined profile of the fringes. In this paper a formulation of moiré phenomenon based on spatial averaging is presented which, without ignoring any of frequencies, leads to a smooth profile.