Fig. 1. Numerical simulation results of pentagram image. (a) Pentagram image; (b) OAM mode decomposition spectrum based on LG modes; (c) object to be imaged that is simulated with a finite superposition of LG modes

Fig. 2. Numerical simulation results of six-leaf clover image. (a) Six-leaf clover image; (b) OAM mode decomposition spectrum based on LG modes; (c) object to be imaged that is simulated with a finite superposition of LG modes

Fig. 3. LG mode decomposition diagram for horizontal Sobel operator

Fig. 4. LG mode decomposition diagram for vertical Sobel operator

Fig. 5. Optical schematic description of 4f quantum correlation imaging system based on BBO crystal

Fig. 6. High-order differential simulation results for six-leaf clover image. (a) 𝓁p=0; (b) 𝓁p=1; (c) 𝓁p=2; (d) 𝓁p=3

Fig. 7. High-order differential simulation results for pentagram image. (a) 𝓁p=0; (b) 𝓁p=1; (c) 𝓁p=2; (d) 𝓁p=3

Fig. 8. Comparison of six-leaf clover simulation results. (a)(e) No differentiation; (b)(f) first-order differentiation; (c)(g) second-order differentiation; (d)(h) third-order differentiation

Fig. 9. Comparison of pentagram image simulation results. (a)(e) No differentiation; (b)(f) first-order differentiation; (c)(g) second-order differentiation; (d)(h) third-order differentiation