Optical security component, fabrication of such a component and secure product equipped with such a component

摘要

An optical security component intended to be checked in reflection in a checking spectral band includes a layer that is reflective in the checking spectral band. The layer exhibits a structured zone that includes microstructures distributed spatially in a uniform manner over a whole of the structured zone so as to form an optical structure that is at least partially scattering in the checking spectral band. The microstructures have heights that are distributed according to a random function, modulated over the structured zone by a modulation function so as to form, after illumination of the optical security component at a given angle, an image identifiable by observation in reflection.

主权项

1. An optical security component intended to be checked in reflection by an acquisition device in a checking spectral band, comprising:
a layer which is reflective in the checking spectral band, wherein the layer is deposited on a structured face of a material layer transparent in the checking spectral band and wherein the structured face exhibits a structured zone comprising: microstructures distributed spatially in a random manner over the whole of the structured zone with a spatial frequency distribution following a lorentzian curve so as to form an optical structure which under illumination in the checking spectral band forms an isotropic diffusing white, wherein the heights of the microstructures are distributed according to a random function, modulated over the zone by a modulation function so as to form, after illumination of the component at a given angle, a first image in grey levels identifiable by observation in direct reflection and a second image in grey levels identifiable by observation in indirect reflection, identical to the first image with the exception of a reversed contrast.