Work

Cryptographic Strain‐Dependent Light Pattern Generators

Year: 2021

Type: article

Abstract: Refractive freeform components are becoming increasingly relevant for generating controlled patterns of light, because of their capability to spatially modulate optical signals with high efficiency and low background. However, the use of these devices is still limited by difficulties in manufacturing macroscopic elements with complex, 3D surface reliefs. Here, 3D‐printed and stretchable magic windows generating light patterns by refraction are introduced. The shape and, consequently, the light texture achieved can be changed through controlled device strain. Cryptographic magic windows are demonstrated through exemplary light patterns, including micro‐QR‐codes, that are correctly projected and recognized upon strain gating while remaining cryptic for as‐produced devices. The light pattern of micro‐QR‐codes can also be projected by two coupled magic windows, with one of them acting as the decryption key. Such novel, freeform elements with 3D shape and tailored functionalities is relevant for applications in illumination design, smart labels, anti‐counterfeiting systems, and cryptographic communication.

Source: Advanced Materials Technologies

DOI: 10.1002/admt.202101129

Authors: Francesca D'Elia, Francesco Pisani, Alessandro Tredicucci, Dario Pisignano, Andrea Camposeo

Institutions: Scuola Normale Superiore, National Enterprise for NanoScience and NanoTechnology, University of Pisa, Istituto Nanoscienze

Language: English

Topic: Advanced optical system design

Subfield: Biomedical Engineering

Field: Engineering

Domain: Physical Sciences

Open Access status: hybrid

Estimated APC paid: $4,200

Funders: European Commission, Consiglio Nazionale delle Ricerche, European Research Council, H2020 European Research Council