Fig. 1. Calculation of central curl

Fig. 2. Calculation of second-order difference

Fig. 3. Phase unwrapping based on central curl segmentation

Fig. 4. Phase information of simulation object. (a) Initial phase; (b) wrapping phase

Fig. 5. Simulation phase unwrapping result. (a) Region where the central curl is not 0; (b) branch-cutting method; (c) least-squares method; (d) central curl segmentation method

Fig. 6. Experimental device diagram

Fig. 7. Phase solution of blade image. (a) Blade experimental diagram; (b) wrapping phase diagram; (c) bivalent mask template; (d) absolute phase diagram

Fig. 8. Blade phase unwrapping results of different algorithms. (a) Branch-cutting method; (b) least-squares method; (c) central curl segmentation method

Fig. 9. Distribution of phase values in the 300th line. (a) Before phase-unwrapping; (b) after phase-unwrapping

Fig. 10. 3D point cloud map of the blade

Fig. 11. Comparison experimental device diagram of blade surface measurement

Fig. 12. Phase solution of gauge block image. (a) Gauge block physical diagram; (b) wrapping phase; (c) absolute phase

Fig. 13. 3D point cloud image of gauge block