The invention relates to an optical security device with multiple hidden images which become visible by arranging a polarizer above or below the device. Additional images become visible upon rotation of the polarizer. The optical device comprises two patterned optical retarders and a polarizer between the retarders.

The invention relates to an optical security device with multiple hidden images which become visible by arranging a polarizer above or below the device. Additional images become visible upon rotation of the polarizer. The optical device comprises two patterned optical retarders and a polarizer between the retarders.

An identification device according to the present invention that performs authenticity determination of an article provided with an anti-counterfeiting medium whose observed light pattern changes depending on an observation angle includes a similarity calculating unit that calculates a degree of similarity between captured image data of the anti-counterfeiting medium and reference image data; an authenticity determination unit that performs authenticity determination as to whether the anti-counterfeiting medium is genuine or not on the basis of whether the degree of similarity exceeds a predetermined threshold or not; and a match-percentage notification unit that notifies a match-percentage indicative of a degree of match between an imaging viewpoint for imaging the anti-counterfeiting medium and a reference imaging viewpoint which is predefined as the imaging viewpoint for the captured image data used for authenticity determination.

An anti-counterfeiting structure includes a substrate having a surface, and an device structure positioned on the surface. A side opposite to the side on which the substrate is positioned with respect to the device structure is an observation side, and the device structure comprises an optical device layer that emits predetermined light towards the observation side, and an information portion that contains given information. The information portion comprises a first substance having optical transparency, wherein the first substance is changeable to a second substance having a different optical characteristic from the first substance by laser irradiation, and the second substance representing information. The device structure has a display surface that is a surface opposite to the surface on which a surface of the substrate, and is configured so as to display information contained in the information portion via the display surface.

A liquid crystal laminate includes a substrate including a first diffraction surface and a second base material surface and having optical transparency, a metal layer located on a part of the first diffraction layer, an adhesion layer located on a part of the second base material layer and made of a photocured resin, and liquid crystal layer located on a surface of the adhesion layer at a side opposite to the contact surface of the substrate.

A liquid crystal laminate includes a substrate including a first diffraction surface and a second base material surface and having optical transparency, a metal layer located on a part of the first diffraction layer, an adhesion layer located on a part of the second base material layer and made of a photocured resin, and liquid crystal layer located on a surface of the adhesion layer at a side opposite to the contact surface of the substrate.

A method for producing a multi-layer body, in particular a security element, in which a partial first layer or partial first layer system is produced on a substrate, wherein the partial first layer or partial first layer system is present in a first partial area and not in a second partial area. Subsequently, a partial second layer or partial second layer system is produced, wherein the partial second layer or partial second layer system is present in a third partial area and not in a fourth partial area, and wherein the third partial area overlaps with the first and second partial areas. Finally, the partial first layer or partial first layer system is structured as a mask using the partial second layer or partial second layer system.

A method for producing a multi-layer body, in particular a security element, in which a partial first layer or partial first layer system is produced on a substrate, wherein the partial first layer or partial first layer system is present in a first partial area and not in a second partial area. Subsequently, a partial second layer or partial second layer system is produced, wherein the partial second layer or partial second layer system is present in a third partial area and not in a fourth partial area, and wherein the third partial area overlaps with the first and second partial areas. Finally, the partial first layer or partial first layer system is structured as a mask using the partial second layer or partial second layer system.

The invention provides a method for generation of an orientation pattern in a photo-alignable material using parallax optic. The invention further provides optical devices comprising a parallax optical element and an element with patterned optical anisotropic properties. Such devices have angular dependent, optically anisotropic properties, which are useful for various applications.

The invention provides a method for generation of an orientation pattern in a photo-alignable material using parallax optic. The invention further provides optical devices comprising a parallax optical element and an element with patterned optical anisotropic properties. Such devices have angular dependent, optically anisotropic properties, which are useful for various applications.