Fig. 1. Continuous phase solution step

Fig. 2. Phase change of four-step phase shift raster image

Fig. 3. Schematic diagram of heterodyne synthesis

Fig. 4. Calculating process of continuous phase diagram. (a) Phase heterodyne synthesis process; (b) phase heterodyne unfolding process

Fig. 5. Physical drawing of parts

Fig. 6. Region of interest (ROI) of continuous phase diagram

Fig. 7. Phase class diagram T₁(x, y)

Fig. 8. Steps of phase class diagram compensation algorithm

Fig. 9. ROI binarization

Fig. 10. Reflection filtering result diagram

Fig. 11. First boundary case

Fig. 12. Processing method for first boundary case

Fig. 13. Processing result of first boundary case

Fig. 14. Second boundary case

Fig. 15. Processing method for second boundary case

Fig. 16. Processing result of second boundary case

Fig. 17. Flow chart of new phase class diagram forming

Fig. 18. Comparison of low frequency phase class diagram before and after phase compensation. (a) T12x,y before phase compensation; (b) T12x,y after phase compensation; (c) T12x,y curve before phase compensation; (d) T12x,y curve after phase compensation

Fig. 19. Comparison of high frequency phase class diagram before and after phase compensation. (a) T1x,y before phase compensation; (b) T1x,y after phase compensation; (c) T1x,y curve before phase compensation; (d) T1x,y curve after phase compensation

Fig. 20. Continuous phase diagram comparison before and after phase compensation. (a) Uncorrected continuous phase diagram; (b) corrected continuous phase diagram; (c) curve of uncorrected continuous phase diagram; (d) curve of corrected continuous phase diagram

Fig. 21. 3D point cloud comparison of parts before and after phase compensation. (a) 3D point cloud of parts before phase compensation; (b) 3D point cloud of parts after phase compensation

Fig. 22. Block point cloud comparison before and after phase compensation. (a) Block point cloud before phase compensation; (b) block point cloud after phase compensation