Fig. 1. Optical layout of the proposed method.

Fig. 2. (a) Close-up view of the test object; (b) schematic diagram of the spatial arrangement of the LDVs; (c) plane view of the test object.

Fig. 3. (a) Interferograms before deformation and after deformation and (b) out-of-plane displacement caused by the vibrations recorded by the LDVs.

Fig. 4. Phase-shifted planes obtained by fitting the data measured by the LDVs at different times.

Fig. 5. (a) Deformation phase obtained by the four-step phase-shifting method; (b) deformation phase obtained by the proposed method; (c) calculation errors of these two methods; (d) data from the cross sections in panels (a)–(c).

Fig. 6. (a) 3D plot and (b) 2D plot at the deformation time t = 3 s; (c) errors of the static measurements and dynamic measurements.

Fig. 7. (a) Deformations at cross section L at different instants and (b) transient deformations of points A, B, and C.