Fig. 4: Self-erasure photonic pattern encryption.

a Schematic diagram of photonic pattern encryption based on direct photo-patterning technique. b The universal patterning fabrication based on three-dimensional (3D) or two-dimensional (2D) mixed halide perovskite films with different perovskite compositions, shapes, and sizes. c, d Schematic and photoluminescence photographs of the decryption and self-erasure process of photonic pattern information. e, f Multiple re-encryption of photonic pattern information, confirming excellent reliability. The figures are extracted from Supplementary Fig. 30. The white number represents the cycle times.