The visualization of a quasi-stable flow field with full 3-D meaning must be provided with 2-D projections. In flow field interferometric tomography, the conventional method of fringe tracking, by which a few solitary 1-D projections are obtained, can evaluate only the 2-D distribution of the field on a limited number of cross sections. A new method that combines Fourier analysis and modified multigrid iteration is proposed to extract 2-D projections from interferograms of the measured field in various directions. On the basis of 2-D projections, the real 3-D field reconstruction can be realized. An experiment with an asymmetric temperature field measurement using a rotary Fabry-Pe´ rot (F-P) interferometer is reported and some cross sections of the reconstructed temperature field are given to prove that the methods of sampling, processing and reconstruction of the algorithm illustrated are effective.
"Real three-dimensional reconstruction of temperature field based on wave-front retrieval," Optical Engineering 37(10), (1 October 1998). https://doi.org/10.1117/1.601806