This disclosure is directed to an electronic identification card or electronic card having various features. The electronic card may include an integrated circuit and a contact plate for electrically interfacing with the integrated circuit. The contact plate may include an array of terminal electrodes that are offset with respect to the edges of the contact plate. The electronic card may be coated with a coating layer that extends at least partially over a ferromagnetic element or film. The electronic card may also include a metal substrate having exposed chamfer portions that may provide a visual contrast to the coating layer and also improve the handling and use of the electronic card.

Directionally dependent optical effects are produced from faceted micrometer-scale substructures. The directionally dependent optical effects can appear as one specific color when viewed from one direction and another specific color when flipped and viewed from the opposing direction. The directionally dependent optical effects may appear reflective or transmissive from one direction and antireflective or opaque when flipped around.

Directionally dependent optical effects are produced from faceted micrometer-scale substructures. The directionally dependent optical effects can appear as one specific color when viewed from one direction and another specific color when flipped and viewed from the opposing direction. The directionally dependent optical effects may appear reflective or transmissive from one direction and antireflective or opaque when flipped around.

Embodiments include luminescent phosphor compounds that include one or more emitting ions and one or more disturbing ions, and methods for their production. An emitting ion in the compound may be characterized by a first decay time constant when the emitting ion is undisturbed. However, a corresponding disturbing ion in the compound, which is different from the emitting ion, causes the emitting ion to have a pre-defined, target disturbed decay time constant that is greater than zero and less than the first decay time constant. An embodiment of an authentication system is configured to measure the decay time constant of a phosphor compound applied to an article, and to determine whether the decay time constant corresponds to a phosphor compound that includes a particular disturbing ion (e.g., in order to determine whether or not the article is authentic).

Embodiments include luminescent phosphor compounds that include one or more emitting ions and one or more disturbing ions, and methods for their production. An emitting ion in the compound may be characterized by a first decay time constant when the emitting ion is undisturbed. However, a corresponding disturbing ion in the compound, which is different from the emitting ion, causes the emitting ion to have a pre-defined, target disturbed decay time constant that is greater than zero and less than the first decay time constant. An embodiment of an authentication system is configured to measure the decay time constant of a phosphor compound applied to an article, and to determine whether the decay time constant corresponds to a phosphor compound that includes a particular disturbing ion (e.g., in order to determine whether or not the article is authentic).

A display body includes lattice lines that are arranged along a plane of incidence on which light is incident. The lattice lines have properties for forming a bright image with diffracted light of the incident light in an oblique view in which the plane of incidence is viewed obliquely, and absorbing some of the incident light. The surface of each of the lattice lines includes dispersed fine step parts that are repetitive in the direction in which the lattice lines extend. The steps have an antireflection function and form a dark image in a front view directly facing the plane of incidence.

A display body includes lattice lines that are arranged along a plane of incidence on which light is incident. The lattice lines have properties for forming a bright image with diffracted light of the incident light in an oblique view in which the plane of incidence is viewed obliquely, and absorbing some of the incident light. The surface of each of the lattice lines includes dispersed fine step parts that are repetitive in the direction in which the lattice lines extend. The steps have an antireflection function and form a dark image in a front view directly facing the plane of incidence.

A data carrier having at least one optically variable element, at least one surface element, and at least one security element comprising at least part of the at least one optically variable element and at least part of the at least one surface element. The at least one surface element is configured to guide impinging electromagnetic radiation towards the at least one optically variable element. The data carrier is configured such, that electromagnetic radiation is impinging on the at least one surface element under at least a first arrival angle when the data carrier is seen under a first observation angle, and such, that electromagnetic radiation is impinging on the at least one surface element under at least a second arrival angle being different from the first arrival angle when the data carrier is seen under a second observation angle being different from the first observation angle. The at least one optically variable element is configured to reflect at least a first reflection spectrum upon impingement of the electromagnetic radiation being impinging on the at least one surface element under the first arrival angle, whereby the at least one security element appears according to at least a first appearance, and is further configured to reflect at least a second reflection spectrum upon impingement of the electromagnetic radiation being impinging on the at least one surface element under the second arrival angle, whereby the at least one security element appears according to at least a second appearance being different from the first appearance.

According to examples, an article may include a base layer that extends along a first dimension and a second dimension, in which the second dimension is orthogonal to the first dimension. The article may also include reflective ribbons provided on an upper surface of the base layer, in which the reflective ribbons positioned along a common plane extending in the second dimension have dihedral angles that change as a function of distance across the common plane.

A transaction card, and processes for the manufacture thereof, having a core layer, optionally, one or more layers or coatings over the core layer, and at least one of a magnetic stripe, a machine readable code, and a payment module chip disposed in or on the card and suitable for rendering the card operable for conducting a transaction. The core layer comprises a metal-doped cured epoxy comprised of metal particles distributed in a binder consisting essentially of a cured, polymerized epoxy resin, the core comprising greater than 50%, preferably greater than 75%, and more preferably greater than 90%, of the weight and/or volume of the card. In some embodiments, the core includes a metal insert enveloped with the metal-doped curable epoxy, wherein the periphery of the epoxy extends beyond the periphery of the metal insert and has material properties more conducive to cutting or punching than the metal insert.