This paper presents a new method for improving the measurement of three-dimensional shapes by using colour information of the measured scene as an additional parameter. The widest used algorithms for 3D surface measurement using structured fringe patterns are phase stepping and Fourier fringe analysis. There are a number of problems and limitations inherent in these algorithms, these include; that the phase maps produced are wrapped modulo 2rr, in some cases the acquired fringe pattern does not fill the field of view, there may be spatially isolated areas and there is often invalid and/or noisy data. The new method presented here uses multiple coloured fringe patterns, which are projected at different angles onto the measured scene. These patterns are analysed using a specially adapted multi-colour version of the standard Fourier fringe analysis method. In this way a number of the standard difficulties outlined above are addressed.
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