Fig. 1. 3D measurement principle of digital fringe projection

Fig. 2. Gamma nonlinear gray response curve

Fig. 3. Effect of two precoding models

Fig. 4. Gamma distribution

Fig. 5. Schematic diagram of level division of fringe pattern

Fig. 6. Effect picture of 81 fringe pattern after precoding correction

Fig. 7. Comparison of fringes generated by different correction methods and fringe gray images collected

Fig. 8. Phase difference plane partial graph

Fig. 9. Reconstruction results of measurement disk