An article for laser marking can comprising: a thermoplastic composition comprising a thermoplastic polymer, an active component comprising at least one of a polymeric unit and an additive, wherein the thermoplastic polymer has a visible transmission of greater than or equal to 80% according to ASTM D1003-00, Procedure A, using D65 illumination, 10 degrees observer, and thickness of 1 mm; and a mark produced by chemical rearrangement of the active component generated by a laser of a first wavelength; wherein the mark exhibits at least one of: (i) a change in optical properties in the region 400 nm to 700 nm when exposed to light having a wavelength less than or equal to 500 nm; and (ii) a change in optical properties in the region of 400 nm to 700 nm when exposed to light having a wavelength greater than or equal to the first wavelength.

A display device includes an electronic paper display imageable by receiving charges on an imaging surface of the electronic paper display, a ground electrode, and a ground access stripe. The ground electrode is opposite to the imaging surface of the electronic paper display. The ground access stripe is on a surface of the display device and electrically coupled to the ground electrode.

A security element (1) for a security paper, value document or the like, having a carrier (8) which has an areal region (3) which is divided into a multiplicity of pixels (4) which respectively includes at least one optically active facet (5), whereby the majority of the pixels (4) respectively have several of the optically active facets (5) of identical orientation per pixel (4), and the facets (5) are so oriented that the areal region (3) is perceptible to a viewer as an area that protrudes and/or recedes relative to its actual spatial form.

A security element (1) for a security paper, value document or the like, having a carrier (8) which has an areal region (3) which is divided into a multiplicity of pixels (4) which respectively includes at least one optically active facet (5), whereby the majority of the pixels (4) respectively have several of the optically active facets (5) of identical orientation per pixel (4), and the facets (5) are so oriented that the areal region (3) is perceptible to a viewer as an area that protrudes and/or recedes relative to its actual spatial form.

Provided are an information recording object and a reading device devised so that embedded information is difficult to guess. The information recording object 30 provided with a combined image comprising an image C1 printed in a lustrous layer 31 and an image C2 formed on the image C1 and printed in a transparent layer 32 is characterized in that: the image C1 and the image C2 are each printed with an ink for which the amount of reflected light differs according to viewing angle; for the combined image, one image is visible depending on the viewing angle; the image C2 is an image in which there is a regularity in feature points in a spatial frequency domain F2; and the image C1 is an image in which the feature points in a spatial frequency domain F1 are disposed at positions that block said regularity.

Provided are an information recording object and a reading device devised so that embedded information is difficult to guess. The information recording object 30 provided with a combined image comprising an image C1 printed in a lustrous layer 31 and an image C2 formed on the image C1 and printed in a transparent layer 32 is characterized in that: the image C1 and the image C2 are each printed with an ink for which the amount of reflected light differs according to viewing angle; for the combined image, one image is visible depending on the viewing angle; the image C2 is an image in which there is a regularity in feature points in a spatial frequency domain F2; and the image C1 is an image in which the feature points in a spatial frequency domain F1 are disposed at positions that block said regularity.

Information is written onto the surface of an object using both an optically identifiable pattern and subregions that exhibit differing magnetic properties. The optically identifiable pattern is printed onto a printed region on the surface of the object using a printing medium that contains magnetic particles. The printed region includes both a first subregion that exhibits a first prevailing magnetization direction and a second subregion that exhibits a second prevailing magnetization direction. The first magnetization direction differs from the second magnetization direction. The first and second magnetization directions are imparted to the first and second subregions by magnetic fields being applied to the magnetic particles. An edge between the first subregion and the second subregion does not coincide with any boundary of the optically identifiable pattern. The printed region contains both optically encoded information and magnetically encoded information. Additional information is decoded using both the optically and magnetically encoded information.

Disclosed are methods and systems that include obtaining at least one image of a dendritic structure, analyzing the at least one image to identify one or more features associated with the dendritic structure, and determining a numerical value associated with the dendritic structure based on the one or more features.

An optical device comprising an at least substantially transparent substrate having a first side comprising a source layer having an arrangement of source elements and a second side comprising an Optically Variable Device (OVD) layer having a corresponding arrangement of diffractive elements, wherein each source element is configured to, upon illumination of the first side, provide an embedded light source for an associated diffraction element, and wherein the diffractive elements are configured for producing an optical effect observable when the diffractive elements are viewed by a viewer, such as the naked eye, upon illumination by the source elements.

A moir magnification device for authenticating security articles, the moir magnification device comprising: an array of micro focusing elements; and an array of micro images; wherein the array of micro focusing elements and the array of micro images are correspondingly aperiodic such that the micro focusing elements generate moir magnifications of the micro image when viewing the device at predetermined viewing angles. A device such as this raises the complexity and difficulty of the task facing would-be counterfeiters. The use of an aperiodic micro focusing element array and micro image array is not immediately apparent, as the moir magnifications observed by the viewer appear the same as that of a regular device with periodic arrays. In this way, the aperiodic aspect of the design remains covert until the moir device is more closely and deliberately analysed.