Optical security component with reflective effect, production of such a component and secure document provided with such a component

Abstract

According to one aspect, the invention relates to an optical security component intended for being observed under direct reflection. The component comprises a structure engraved on a layer of a material having a refraction index n, a thin layer of a dielectric material having a refraction index nother than n, deposited on the structure, and a layer of a material having a refraction index no other than n, encapsulating the coated structure of the thin layer. The structure has a first pattern modulated by a second pattern such that, in at least one first region (), the first pattern comprises a low-relief with a first set of facets, the shapes of which are determined such as to generate at least one first concave or convex cylindrical reflective element, and the second pattern forms a first subwavelength grating acting, after depositing the thin layer and encapsulating the structure, as a first wavelength-subtractive filter; in at least one second region (), the first pattern comprises a low-relief with a second set of facets in which the shapes are determined such as to generate at least one concave or convex cylindrical reflective element (), and the second pattern forms a second subwavelength grating acting, after depositing the thin layer and encapsulating the structure, as a second wavelength-subtractive filter, separate from the first wave-length-subtractive filter. Each subwavelength grating can be a zero order diffraction grating such as a DID.