A new algorithm for large surfaces profiling by fringe projection

A method for profiling surface objects based on the fringe projection method and a phase shifting algorithm is described. The application of this method to large surfaces is problematic since the calibration step requires the use of a reference plane as large as the object. A new algorithm based on least-squares method has also been developed to bypass this calibration step, and so the use of a reference plane. First experimental results on a carbon panel and on a parabolic aerial are presented to show the validity of the proposed algorithm. Accuracy of 1 mm has been obtained for an object of 1 m and 20 cm long, while sensitivity has been proved to be of the order of 100 mum. (C) 2004 Elsevier B.V. All rights reserved.