Fig. 1. Schematic diagram of FPP system

Fig. 2. Schematic diagram of complex texture object measurement under camera defocus

Fig. 3. Simulation experiments. (a) Test object before defocus; (b) the first horizontal phase shift fringe of test object before defocus; (c) the first vertical phase shift fringe of test object before defocus; (d) test object after defocus; (e) the first horizontal phase shift fringe of test object after defocus; (f) the first vertical phase shift fringe of test object after defocus; (g) horizontal phase error; (h) vertical phase error

Fig. 4. Experimental process for phase error model derivation. (a) Relationship form various angles; (b) relationship between phase error and pinch angle

Fig. 5. Phase correction method for complex textured objects based on bidirectional fringe projection

Fig. 6. Phase gradient angle correction. (a) Phase gradient angle correction method; (b) comparison of phase gradient angle error before and after correction

Fig. 7. Phase mapping method

Fig. 8. Experimental setup diagram

Fig. 9. Measurement process of circular calibration plate. (a) Horizontal fringe image captured; (b) vertical fringe image captured; (c) original horizontal phase; (d) phase converted to vertical direction; (e) difference between phase converted to vertical direction and original vertical phase; (f) corrected phase

Fig. 10. Error distribution of circular calibration plate. (a) TFH; (b) TFV; (c) TFReH; (d) Ref. [8] method; (e) the proposed method

Fig. 11. Card holder measurement results. (a) Card holder image; (b) error distribution of TFH; (c) error distribution of TFV; (d) error distribution of TFReV; (e) error distribution of Ref. [8] method; (f) error distribution of the proposed method

Fig. 12. Comparison of one-dimensional cross-section for error of card holder. (a) Card holder image; (b) comparison of various methods

Fig. 13. Vase measurement results. (a) Vase image; (b) point cloud of TFH; (c) point cloud of TFV; (d) point cloud of TFReH; (e) point cloud of Ref. [8] method; (f) point cloud of the proposed method

Fig. 14. Standard step block. (a) Initial step block; (b) step block with texture

Fig. 15. Error distribution of step block. (a) TFH; (b) TFV; (c) TFReH; (d) Ref. [8] method; (e) the proposed method