VISUALIZATION OF FRINGES IN TIME AVERAGED MOIRE PATTERNS

Abstract

Time averaging interferometry is an experimental technique widely applied in different areas of optical engineering. Typical example is an application of time averaging techniques for the analysis of fringes produced by a moiré grating formed on the surface of oscillating elastic structure. Unfortunately, time averaged moiré produces blurred images. Therefore, special digital image filtering is to be used for highlighting the pattern of time averaged fringes. Such a procedure is essential for the investigation of dynamical systems with non-harmonic motion as the produced moiré pattern is particularly blurred. This paper proposes some techniques for the sharpening of fringes in time averaged moiré patterns.