Using several hologram plates for measurement of 3D-displacement a problem arises that the object looks different from different directions, so that the fringes become difficult to identify. It will be shown that recording three or more interferograms on a single plate the components of displacement vector can be determined to a higher accuracy. A 3-D displacement measurement has been reported using technique of regulated path length interferometry resulting in three independent interferograms on a single plate.
"Measurement Of 3D-Displacement By Regulated Path Length Interferometry", Proc. SPIE 0398, Industrial Applications of Laser Technology, (26 October 1983); doi: 10.1117/12.935350; https://doi.org/10.1117/12.935350