Fig. 1. Diagrams of optical encryption and decryption systems. (a) Encryption system; (b) decryption system

Fig. 2. Schematic of optical multi-image encryption based on JPS partition multiplexing

Fig. 3. Flow chart of phase mask design

Fig. 4. Schematic of key content planning

Fig. 5. Images to be encrypted

Fig. 6. Schematic of spliced JPS in horizontal direction

Fig. 7. Phase masks. (a) Key phase kernel k'; (b) object window phase kernel h'; (c) generated key phase mask k'1; (d) generated object window phase mask h'1

Fig. 8. Schematic of encryption and decryption processes. (a) Input plane of channel 1; (b) JPS of channel 1; (c) superimposed cipher-text of nine channels; (d) power spectrum from key mask of channel 1; (e) decrypted images of nine channels

Fig. 9. Decrypted images. (a) Decrypted image with correct key; (b) decrypted image with incorrect key

Fig. 10. Relationship between CC value and horizontal offset of deflection angle. (a) Channel 1; (b) channel 2; (c) channel 3; (d) channel 4; (e) channel 5; (f) channel 6; (g) channel 7; (h) channel 8; (i) channel 9

Fig. 11. Relationship between CC value and Ef

Fig. 12. Experimental system of optical encryption. (a) Schematic; (b) experimental platform

Fig. 13. Keys used in experiment. (a) Key phase kernel k'; (b) object window phase kernel h'; (c) key phase mask k'5; (d) object window phase mask h'5

Fig. 14. Schematic of encryption and decryption processes. (a) Input plane of channel 5; (b) JPS of channel 5; (c) power spectrum from key mask of channel 5; (d) superimposed cipher-text of six channels; (e) decrypted images of six channels