Electronic processing of moiré fringes: application to moiré topography and comparison with photogrammetry

Some elements of comparison are given between projection-type moiré topography and photogrammetry. The basic mathematics of photogrammetry is used to reconstruct the 3-D shape of the object from the moiré pattern. Some particular aspects of the moiré method are discussed, and a general methodology is proposed. In connection with this, an optoelectronic technique is described, which measures the moiré phase with high resolution and sign determination. The experimental results show that this technique is especially suitable for high accuracy automatic reconstruction of 3-D shapes.