The invention relates to a data carrier comprising a storage layer forming a plurality of first surface elements (6). The storage layer (2) has at least one optical characteristic, which is optically anisotropic and which varies spatially between the first surface elements (6). A cover layer (3) over the storage layer (2) forms a plurality of second surface elements (10), each acting as a polarisation filter for a predetermined polarisation direction. The predetermined polarisation direction varies between the second surface elements (10). The storage layer can contain in particular bacteriorhodop sin in the form of a purple membrane. The invention also relates to a method for the production and reading of a data carrier of this type.

The invention relates to a data carrier comprising a storage layer forming a plurality of first surface elements (6). The storage layer (2) has at least one optical characteristic, which is optically anisotropic and which varies spatially between the first surface elements (6). A cover layer (3) over the storage layer (2) forms a plurality of second surface elements (10), each acting as a polarisation filter for a predetermined polarisation direction. The predetermined polarisation direction varies between the second surface elements (10). The storage layer can contain in particular bacteriorhodop sin in the form of a purple membrane. The invention also relates to a method for the production and reading of a data carrier of this type.

A micro-optic security device with zonal color transitions includes a planar array of focusing elements, an image icon layer including a plurality of retaining structures, the plurality of retaining structures defining isolated volumes at a first depth within the image icon layer, a first zone of image icons, the first zone of image icons having a first predefined subset of the plurality of retaining structures, wherein the isolated volumes of retaining structures of the first predefined subset of the plurality of retaining structures contain cured pigmented material of a first color, and a second zone of image icons, the second zone of image icons including a second predefined subset of the plurality of retaining structures, wherein the isolated volumes of retaining structures of the second predefined subset of the plurality of retaining structures contain cured pigmented material of a second color, wherein the second color contrasts with the first color.

A micro-optic security device with zonal color transitions includes a planar array of focusing elements, an image icon layer including a plurality of retaining structures, the plurality of retaining structures defining isolated volumes at a first depth within the image icon layer, a first zone of image icons, the first zone of image icons having a first predefined subset of the plurality of retaining structures, wherein the isolated volumes of retaining structures of the first predefined subset of the plurality of retaining structures contain cured pigmented material of a first color, and a second zone of image icons, the second zone of image icons including a second predefined subset of the plurality of retaining structures, wherein the isolated volumes of retaining structures of the second predefined subset of the plurality of retaining structures contain cured pigmented material of a second color, wherein the second color contrasts with the first color.

[Problem] To provide a luminescent sheet having an excellent light emission performance and capable of preventing forgery.

[Solution] A luminescent sheet 1 has a first base material layer, at least one of recesses 3 and projections 4 having edges and formed on a first base material layer 2, and stress-luminescent parts each arranged at a location contacting with the edge. At least a part of the edges has a stress concentrated part where stress concentrates when stress is added to the first base material layer in a predetermined direction. The stress-luminescent part emits light having a predetermined wavelength with a light-emitting intensity depending on external load stress added to the stress concentrated part.

[Problem] To provide a luminescent sheet having an excellent light emission performance and capable of preventing forgery.

[Solution] A luminescent sheet 1 has a first base material layer, at least one of recesses 3 and projections 4 having edges and formed on a first base material layer 2, and stress-luminescent parts each arranged at a location contacting with the edge. At least a part of the edges has a stress concentrated part where stress concentrates when stress is added to the first base material layer in a predetermined direction. The stress-luminescent part emits light having a predetermined wavelength with a light-emitting intensity depending on external load stress added to the stress concentrated part.

The present invention relates to a structure for a physical unclonable function using spontaneous chiral symmetry breaking and a method of preparing the same, in which a chiral random pattern, which is unclonable and is observable with an optical microscope and a mobile phone camera, is formed using chiral photonic crystals in which chiral symmetry breaking occurs and is applied to a physical unclonable function (PUF), thereby attaining high encoding capacity, high recognition rate, and security while achieving high performance in reproducibility, uniqueness, unpredictability, and reconfigurability, and forming a desired pattern through a conventional photolithography method.

A system and associated method, the system including an item including a porous polymer layer including a polymer material capable of absorbing a liquid, the polymer material having an index of refraction that is the same or substantially the same as an index of refraction of the liquid, and a substrate layer, where the porous polymer layer is disposed on the substrate layer, and a liquid source comprising the liquid, where the porous polymer layer appears transparent in response to absorption of the liquid from the liquid source by the porous polymer layer.

A system and associated method, the system including an item including a porous polymer layer including a polymer material capable of absorbing a liquid, the polymer material having an index of refraction that is the same or substantially the same as an index of refraction of the liquid, and a substrate layer, where the porous polymer layer is disposed on the substrate layer, and a liquid source comprising the liquid, where the porous polymer layer appears transparent in response to absorption of the liquid from the liquid source by the porous polymer layer.

A security device that exhibits at least one dynamic response upon change of orientation of the security device with respect to gravity, wherein the security device includes a hollow capsule completely filled with a liquid and one or more microscopic elements. In addition, the dynamic response continues after cessation of the change of orientation with respect to gravity. The dynamic response includes a transition of the one or more microscopic elements from substantial mechanical equilibrium to non-equilibrium upon action of the change of orientation with respect to gravity and back to substantial mechanical equilibrium after cessation of the change of orientation with respect to gravity. During the dynamic response, the one or more microscopic elements undergo at least one of a rotational motion and a translational motion relative to the liquid.