Fig. 1. Schematic diagram of single subaperture spot centroid calculation

Fig. 2. Schematic diagram of microlens diffraction

Fig. 3. Schematic diagram of microlens array diffraction imaging

Fig. 4. Central intensity distribution of (a) any diffraction spot and (b) any non diffraction spot

Fig. 5. Simulated spot diagram after discretization

Fig. 6. Centroid calculation error in the process of (a) diffraction free and (b) diffraction spot shifting by 1 pixel; (c) calculation error of centroid caused by diffraction effect

Fig. 7. (a) Reconstructed wavefront with diffraction free spot offset of 0.79 pixels; (b) reconstructed wavefront with diffraction spot offset of 0.79 pixels; (c) maximum error wavefront

Fig. 8. (a)Wavefront tilt error in the process of diffraction free spot shifting by 1 pixel; (b) wavefront tilt error in the process of diffraction spot shifting by 1 pixel; (c) wavefront tilt error caused by diffraction effect

Fig. 9. Relative error

Fig. 10. Experimental diagram of Hartmann wavefront detection device

Fig. 11. (a) Experimental spot diagram; (b) initial warefront (c) inclined wavefront

Fig. 12. (a) Relation curve between actual wavefront tilt and rotation angle; (b) relationship curve between simulated wavefront tilt and rotation angle; (c) relation curve between experimental wavefront tilt and rotation angle; (d) wavefront tilt error curve