Open AccessFabrication of diffraction based security elements using direct laser interference patterning
Author(s) -
Florian Rößler,
Tim Kunze,
Andrés Fabián Lasagni
Publication year - 2017
Publication title -
optics express
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.25.022959
Subject(s) - optics , holography , materials science , laser , diffraction grating , diffraction , grating , diffraction efficiency , fabrication , optoelectronics , physics , medicine , alternative medicine , pathology
Product piracy impacts wide areas of the global economy resulting in multi-billion dollar losses per year. Therefore, product protection technologies are required to produce security elements with high flexibility and complexity. In this work, the fabrication of diffraction-based security elements, so called grating cell arrays, using direct laser interference patterning is presented. Ultraviolet two-beam interference patterning is used to structure line-like gratings into 80 µm in diameter spots with spatial periods ranging from 0.7 µm to 2.2 µm on PET substrates. The developed grating cell arrays are generated by the combination of several holographic surface gratings with variable spatial period and pattern orientation. The stored security information can be visualized by illumination with a coherent light source such as a laser pointer.