Asian Journal of Physics Vol. 35, Nos 1 – 3 (2026) 77-102

Optical encryption using joint transform correlators:opto-digital implementations

John Fredy Barrera-Ramírez and Alejandro Velez-Zea
Grupo de Óptica y Fotónica, Instituto de Física, Facultad de Ciencias Exactas y Naturales,
Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín, Colombia

In memory of Professor Gallieno Denardo, ICTP Italy

This paper presents a comprehensive review of experimentally validated opto-digital joint transform correlator (JTC) cryptosystems, classified according to the transform domain in which they operate: Fourier, Fresnel (free-space), and fractional. Particular attention is given to implementations that incorporate the suppression of non-significant terms, multiplexing strategies, and the use of physical random phase masks, all of which are essential in realistic optical cryptosystems. The review additionally examines single-arm JTC configurations, which do not use an external reference arm to record the encryption key, leading to compact and secure architectures with reduced setup complexity. Overall, this review consolidates the main advances in opto-digital JTC encryption and highlights the experimental trends that define current and emerging cryptosystem designs. © Anita Publications. All rights reserved.
Doi: XXX
Keywords: Experimental optical encryption, Joint transform correlator, Double random phase encoding, Opto-digital cryptosystems, Reference-free cryptosystem.

Peer Review Information
Method: Single- anonymous; Screened for Plagiarism? Yes
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