Adaptive projection moiré method for arbitrarily arranged light path system.

ABSTRACT

In the projection moiré method, the projected fringe with a constant period usually generates a moiré pattern with nonuniform fringe spacing, which increases the low modulation regions and local measurement error. In this work, an adaptive moiré pattern generation method for the projection moiré system is developed. By formulating the relationship between the surface contour and moiré fringe spacing, the period of the projected fringe is modulated to acquire a uniform moiré pattern and highly improve the full-field measurement precision. The corresponding calculation algorithm is developed to obtain the 3D morphology. The proposed method is applicable to an arbitrarily arranged projection moiré system on any continuous surface without the phase jump error. A series of experiments are carried out, and the results are discussed in detail.