Abstract

When it is carried out to perform a three dimensional evaluation of displacements and strains, it has been proposed some optical systems which uses three illumination beams or the use of three sensors. The different sensitivity vectors components associated to each illumination beam; let us permit to calculate the displacement in each direction by sensitivity matrix. In the present work, simple geometries of interferometers are discussed. It is showed the sensitivity components for each source in the case of optical set-up with three divergent illuminating beams, where we analysed the sources position that makes possible measure the u, v and w components with a maximum weight factor in each direction respecting to set-up total sensitivity. The sources position is one on x-axis, the second on y-axis and the third near to z-axis. From the theoretical predictions is proposed an interferometer which is based on the ESPI technique which has the sources configuration calculated. Experimental results of displacements are presented to an elastic surface when a rotated load is applied in the centre of the target.