摘要:
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 n2, a thin layer of a dielectric material having a refraction index n1 other than n2, deposited on the structure, and a layer of a material having a refraction index no other than n1, 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 (61, 86), 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 (62, 86), 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 (64), 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.
摘要:
According to one aspect, the invention relates to a customizable document for producing a customized security document (10, 20). The customizable document includes, according to an alternative: a layer (12) which can be customized by contact-free writing an opaque customization mask that is transparent in at least one transparency area (121); a first multilayer film (102) arranged on a first side of the customizable layer (12), including a layer having a high refractive index and encapsulated between two layers having a low refractive index, and structured over at least a portion of the surface thereof such as to form a first subwavelength array, characterized by a first array vector, such that the first multilayer film acts at zero order as a wavelength subtractive filter; a second multilayer film (102) arranged on a second side of the customizable layer, opposite the first side, including a layer having a high refractive index and encapsulated between two layers having a low refractive index, and structured over at least a portion of the surface thereof such as to form a second subwavelength array characterized by a second array vector, such that the second multilayer film acts at zero order as a wavelength subtractive filter, the first and second arrays being at least partially stacked.
摘要:
An ID document comprises a receiving substrate in or on which an ink that is fluorescent under UV-A lighting is locally deposited, and a multilayer optical security component attached to a substrate. The optical component comprises a structurable layer and a reflective dielectric layer discontinuously deposited on the structurable layer in the plane of the component so as to produce patterns. The reflective dielectric layer has a relative transmission of at most 40% in the UV-B or UV-C range. The optical component also include an assembly of at least one layer including pigments that are fluorescent when energized by UV-B or UV-C. These are deposited on the reflective dielectric layer in a uniform or discontinuous manner in the plane of the optical component.
摘要:
A method of securing a redundant initial two-dimensional barcode includes providing an initial message having a unique identifier, encoding the initial message as a set of predefined symbols so as to generate a redundant initial two-dimensional barcode having a redundant zone, generating a unique secret character string having a predefined fixed size, encoding the unique secret character string as a set of predefined symbols identical to the symbols used to generate the redundant initial two-dimensional barcode, and inserting the encoded unique secret character string into a redundant zone of the redundant initial two-dimensional barcode, each symbol of said encoded unique secret character string having a predefined position, so as to create a final two-dimensional barcode.
摘要:
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 n2, a thin layer of a dielectric material having a refraction index n1 other than n2, deposited on the structure, and a layer of a material having a refraction index n0 other than n1, 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 (61, 86), 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 (62, 86), 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 (64), 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.