Researchers unveil pixel-resolved optical encryption method

A Shenzhen University and BGI Research team says it has built a new optical encryption system that controls light at the pixel level to raise security and expand the key space. The work, published Oct. 13 in Opto-Electronic Technology, aims to counter weaknesses in older holographic encryption systems that rely on global Fourier transforms.

Why it matters: - The new approach could make optical encryption harder to break by expanding the number of variables an attacker would need to guess. - The method is designed to support higher-capacity information security by controlling light’s spatial position, polarization and orbital angular momentum separately. - The publication says traditional optical encryption systems are limited by global coupling and can be vulnerable to iterative retrieval algorithms.

What happened: - A research team led by Prof. Junle Qu at Shenzhen University’s Medical Photonics Innovation Institute, working with Mengzhe Shen and Dapeng Wang at BGI Research, proposed a “vectorial optical pen.” - The team says it achieved a multiple degrees-of-freedom optical encryption system with pixel-resolved resolution for the first time. - Opto-Electronic Technology published the paper on Oct. 13, 2026. - The article’s DOI is 10.29026/oet.2026.260018.

The details: - The method lets researchers independently control the focus on the imaging plane across spatial location, polarization and orbital angular momentum. - The researchers say that decoupling spatial distribution from multiple physical dimensions reduces coherent crosstalk between modes. - On the encryption side, the team converted example information such as the letters “S,” “Z” and “U” into ASCII codes and encoded them into holographic phase data. - On the decryption side, only incident light with the correct polarization state and orbital angular momentum parameters can reconstruct the information. - Incorrect parameters distort the optical field and prevent decoding. - The team also used quantitative probability analysis and a morphological crossing-feature extraction algorithm to evaluate resistance to interference and unauthorized decryption. - The paper says the analysis showed very low crosstalk and strong joint decoding probability. - The research was supported by China’s National Key R&D Program, the National Natural Science Foundation of China, Shenzhen key laboratories in photonics and biomedical optics, and the Shenzhen Science and Technology Program.

Between the lines: - The paper is pushing optical encryption away from broad, globally coupled holographic control and toward finer local control at the pixel level. - That shift matters because finer control usually means a larger key space and more room to stack security conditions. - The “vectorial optical pen” framing suggests the system is intended as a platform concept, not just a one-off encoding demo. - The claims about robustness and low crosstalk are technical advantages, but the practical value will depend on how the system performs outside the lab.

What's next: - The authors position the method as a practical path toward high-capacity, high-security micro-optical information encryption systems. - Further work will likely focus on testing the system under broader operating conditions and proving it can scale beyond the reported demonstration. - The journal lists more information at the journal website.