Master key generation to avoid the use of an external reference wave in an experimental JTC encrypting architecture

Abstract

In experimental optodigital encrypting architectures, the use of a reference wave is essential. In this contribution, we present an experimental alternative to avoid the reference wave during the encrypting procedure in a joint transform correlator architecture by introducing the concept of a master key. Besides, the master key represents an additional security element for the entire protocol. In our method, the master key is holographically processed and used during the encryption process with the encrypting key. We give the mathematical description for the process in case of a single input object and then we extend it to multiple input objects. We present the experimental demonstration of the proposed method including two examples where this technique is successfully applied for several input objects.

Application of the fractional Fourier transform for decryption in experimental optical cryptosystems

“…Alternatively, opto-digital cryptosystems have been proposed as a way to overcome some of the experimental limitations of the 4f and the JTC architectures [12][13][14][15][16][17][18]. In optodigital cryptosystems, encryption is carried out optically, while decryption is conducted digitally.…”

“…This method involves recording the encrypted object and the security key using a digital camera. In particular, several opto-digital approaches have been proposed and validated experimentally for the JTC cryptosystem, including methods that use a reference beam [12,19], a master key [17], phase-shifting interferometry [14], and phase-retrieval algorithms [20]. Likewise, proposals involving impulse illumination [16] or phase shifting interferometry with two spatial light modulators (SLMs) [21] have been numerically validated, but their experimental implementation is challenging.…”

Speckle-suppressed optical implementation for JTC-based image cryptosystem

“…In this regard, E. Rueda et al propose an optical encryption scheme with a reference wave in a JTC architecture [6]. On this basis, they reported a master key generation method to avoid the use of external reference wave in an experimental JTC encryption architecture [7]. In this scheme, the requirements of stability and alignment for an interferometric is relaxed and fewer optical elements are used.…”

A Robust Optical Encryption Method for Three-Dimensional Object Based on the Fresnel Transform

“…Optical digital holographic encryption technique was developed and popularized recently owning to its advantages of conveniences of data recording, transmission, and processing [11]- [14]. Various optical digital holographic encryption methods have been in use such as two, three, or four steps phase shift interference methods [15]- [18].…”