Secure and noise-free holographic encryption with a quick-response code

In holographic encryption, double random-phase encoding in the Fresnel domain （DRPEiFD） is a preva- lent encryption method because it is lensless and secure. However, noises bring adverse effects during decryption. In this letter, we introduce quick-response （QR） coding during encryption to resist noises. We transform the original information into a QR code and then enerypt the code as a hologram through DRPEiFD. To retrieve the input, we deerypt the hologram in the opposite manner to the encryption and subsequently obtain a QR code with noises. By scanning this code with proper applications in smart- phones, we can obtain a noise-free retrieval. Numerical experiments and images scanned by a smartphone are shown to validate our proposed method.