Abstract: The invention relates to an optically variable element which at least in surface portions has an interface embedded between two layers and which forms an optically effective structure, that interface having a free-form surface which appears three-dimensionally for a viewer. To emphasise that free-form surface the invention provides that the free-form surface is formed by a partial region of the interface, which is of a lens-like configuration and which produces a magnification, reduction or distortion effect. The invention also provides the use of such optically variable elements as a security element to prevent forgery of value-bearing documents or for articles to be safeguarded, in particular as part of the decorative layer arrangement of a transfer or laminating film.

Abstract: Described is a security element for increasing the forgery-proof nature of a security document, in particular an identity card or pass, a passport or an identification card. The security element (1) has a first diffractive region (15) having an open code which is visible with a naked eye. The first diffractive region further has a concealed code which is not visible with the naked eye and which can be reconstructed from the arrangement of diffractive microregions disposed in the first region (1) and/or from the structure of the first diffractive region (1). Further described is a method of increasing the forgery-proof nature of a security document.

Abstract: Described is a multi-layer body (10i) comprising an optically machine-readable identification, wherein the multi-layer body has at least one first plastic material layer with a microscopically fine relief structure shaped in that layer and the optical effect of the microscopically fine relief structure can be altered region-wise for writing in an item of information. First and second regions have different relief structures and form a background pattern (1 through 7) which encodes a first item of information and which is partially altered for writing in an individualised code pattern (1i through 3i) which encodes an individualised second item of information and which overlaps the background pattern. There is also described a method of manufacturing such a multi-layer body and a method of reading the items of information.

Abstract: There is described a process for the production of a multi-layer body (100) having a partially shaped first layer (3m), wherein it is provided that in the process a diffractive first relief structure (4) with a high depth-to-width ratio of the individual structure elements, in particular with a depth-to-width ratio of >0.3, is shaped in a first region (5) of a replication layer (3) of the multi-layer body (100) and the first layer (3m) is applied to the replication layer (3) in the first region (5) and in a second region (4, 6) in which the relief structure is not shaped in the replication layer (3), with a constant surface density, and the first layer (3m) is partially removed in a manner determined by the first relief structure so that the first layer (3m) is partially removed in the first region (5) or in the second region (4, 6) but not in the second region (4, 6) or in the first region (5) respectively.

Abstract: There is described a security element having at least one optically variable device, in which at least one layer of the optically variable device is in the form of an electrically active layer (13, 14) of an electronic component and/or an electronic circuit.

Abstract: The invention concerns a security element (1) and a value-bearing document safeguarded by such a security element. The security element (1) includes a strip-form multi-layer body (10) with a carrier film (11) and at least one decorative layer (12), as well as a first and a second adhesive layer (14, 15). The first adhesive layer (14) is provided on a first surface of the multi-layer body (10). The second adhesive layer (15) is provided on an opposite second surface of the multi-layer body. The security element has two or more first regions (21) in which the first adhesive layer (14) respectively covers the first surface of the multi-layer body and two or more second regions (22) in which the second but not the first surface of the multi-layer body is respectively covered by the second and the first adhesive layer respectively and in which a surface structure is respectively formed in the first surface. First and second regions (21, 22) are in this case arranged in mutually juxtaposed adjacent relationship.

Abstract: The invention concerns a security document (1) comprising a transparent window (12) in which a first optical element (15) is arranged and a second transparent window (13) in which a second optical element (16) is arranged. The first transparent window (12) and the second transparent window (13) are arranged on a carrier (11) of the security document (1) in mutually spaced relationship in such a way that the first and the second optical elements (15, 16) can be brought into overlapping relationship with each other. The first optical element (15) has a first transmissive microlens field and the second optical element (16) has a second transmissive microlens field, wherein a first optical effect is produced upon overlap of the second microlens field with the first microlens field.

Abstract: The invention concerns an optical security element having a substrate layer, in which a first microstructure for producing a first optically perceptible effect is shaped region-wise in a surface region. The surface region is divided into microscopically fine pattern regions and a background region. The first microstructure is shaped in the pattern regions but not in the background region. The microscopically fine pattern regions in the surface region are arranged in the form of a moire pattern into which a concealed item of information which can be evaluated by means of an associated verification element is encoded as a security feature. The microscopically fine pattern regions are further substructured in accordance with a substructuring function which describes a microscopic substructuring, serving as a further security feature, of the moire pattern.

Abstract: A layer arrangement is proposed, particularly for transfer films or laminated films, which exhibits at least two superposed synthetic resin layers, between which there is provided an interface surface having a refractive structure producing a lens-like effect, the novelty claimed being a special design of the structure having a diffractive effect.

Abstract: The present invention relates to an optically variable element having surface portions with achromatic surface structures and different scatter, diffraction and reflection characteristics. The achromatic surface structures are combined with a thin-film structure, whereby upon turning or tilting the optically variable element, it is not the impression of a continuous color transition, but a defined, almost discrete color change that is produced for the viewer.

Abstract: A security element (2) comprising a reflective, optically variable surface pattern (3) which is embedded in a layer composite of plastic material and which can be visually recognized from predetermined observation directions is formed from a mosaic of optically active surface elements (13). In the mosaic of the surface pattern (3) at least two of the mosaic surfaces (11; 12) of the surface pattern (3) are arranged substantially adjacent and have microscopically fine light-diffractive relief structures (4). The spatial frequencies of the relief structures in the mosaic surfaces (11; 12) are of values from predetermined spatial frequency ranges in such a way that, in the case of illumination beams which are incident obliquely relative to a normal onto the plane of the layer composite, the relief structures of the mosaic surfaces (11; 12) deflect visible monochromatic light parallel to the normal (32).

Abstract: A security element (2) in the form of a laminate can be used for the authentication of a document (1). The laminate has at least a transparent protective layer, a transparent lacquer layer and an adhesive layer, the lacquer layer being arranged between the protective layer and the adhesive layer. An interface in the form of a reflection layer separates the adhesive layer and the lacquer layer. The interface is divided into regions of a pattern (25) with flat surface portions and with relief structures which are formed in the lacquer layer. The flat surface portions form background surfaces (3) providing flat mirror surfaces for light which is incident into the laminate, while the regions with the relief structures of a predetermined, optically effective structure depth form pattern elements (4). The relief structures of the pattern elements (4) absorb the incident light.

Abstract: A diffractive security element (2) is divided into surface portions, having an optically effective structure (9) at interfaces embedded between two layers of a layer composite (1) of plastic material. At least the base layer (4), which is to be illuminated, of the layer composite (1) is transparent. The optically effective structure (9) as a base structure has a zero order diffraction grating with a period length of at most 500 nm. In at least one of the surface portions an integrated optical waveguide (5) with a layer thickness (s) of a transparent dielectric is embedded between the base layer (4) and an adhesive layer (7) of the layer composite (1) and/or a protective layer (6) of the layer composite (1), wherein the profile depth of the optically effective structure (9) is in a predetermined relationship with the layer thickness (s).

Abstract: A decorative foil is in the form of a layer composite structure (1) and comprises at least a transparent base foil (2), a transparent cover layer (4) and a transparent dielectric layer (3) arranged between the base foil (2) and the cover layer (4). When the decorative foil serves as a lamination foil for a substrate (5) the material of the cover layer (4) is an adhesive. A reflective metallic layer (6) is arranged at least in surface portions between the dielectric layer (3) and the cover layer (4) and optionally a metal film (11) is also arranged on the side of the dielectric layer (3) facing the base foil (2). General items of information shown by the decorative foil are produced by means of modulation of the thickness (s) of the dielectric layer (3). Transparent locations (7) form individual items of information, wherein the transparent locations (7) are produced with a laser beam (19) by perforating the metal layer (6; 11).

Abstract: A security element for sticking onto a document comprises a layer composite of plastic material and has embedded, optically effective structures of a pattern . The optically effective structures in surface portions of the pattern are in a reference plane, defined by co-ordinate axis (x; y), of the layer composite and are shaped into a reflecting interface. The interface is embedded between a transparent shaping layer and a protective layer of the layer composite. At least one surface portion is of a dimension of greater than 0.4 mm and in the interface has at least one shaped macrostructure which is an at least portion-wise steady and differentiatable function of the co-ordinates (x; y). The macrostructure is curved at least in partial regions and is not a periodic triangular or rectangular function. In the surface portion adjacent extreme values of the macrostructure are at least 0.1 mm away from each other.

Abstract: An optically variable surface pattern (1) contains relief structures (9.1; 9.2; 9.3) for producing at least two representations (2; 3; 4). The relief structures (9.1; 9.2; 9.3) have a period length (L) of at least five micrometers and are sawtooth-shaped. The relief structures (9.1; 9.2; 9.3) associated with different representations (2; 3; 4) have different angles of inclination (?;?;?). The angles of inclination are so selected that the representations (2; 3; 4) can be perceived separately by a viewer on the one hand and on the other hand when producing a copy by means of a color photocopier they are all transferred onto the copy.

Abstract: A layer composite of plastic material forms a retroreflector and includes at least one transparent structure layer, a protective layer and a reflection layer enclosed at the common interface between the structure layer and the protection layer. A relief structure formed by substantially identically shaped three-dimensional structure elements is formed in the reflection layer. At their base surfaces the structure elements are of lateral dimensions in the range of between 1 ?m and 100 ?m. The structure elements have side faces which are covered by the reflection layer and which include an angle of inclination of 45°, with a free surface of the layer composite. The relief structure is additively superimposed with a microstructure in at least one surface element. The microstructure has a preferred direction and influences the quality of the reflection action of the layer composite. The retroreflector is suitable for the production of machine-readable optical markings.

Abstract: A label (1) made from a layer composite (15) includes at least one machine-readable diffractive bar code (3) consisting of narrow rectangular fields (4) occupied by the optically active structures and intermediate surfaces (5). The optically active structures which are covered by a reflection layer are embedded between layers of the layer composite (15). The diffractive relief structure used in the diffractive bar code (3) for the fields (4) diffracts and polarizes incident light and scatters the diffracted light into a half-space above the diffractive relief structure. A second diffractive relief structure differs at least in respect of the polarization of the polarizedly backscattered light with respect to the first diffractive relief structure. The second diffractive relief structure can be used for example for field surfaces of a second bar code in the bar code field (9) on the label (1) or for the intermediate surfaces (5).

Abstract: A security element (2) comprising a plastic laminate (1) has a surface pattern which is composed mosaic-like at least from surface elements, wherein in the surface elements a reflecting interface (8) between a shaping layer (5) and a protective layer (6) of the plastic laminate (1) forms optically effective structures (9). Light (11) which is incident on the plastic laminate (1) and which passes through a cover layer (4) of the plastic laminate (1) and through the shaping layer (5) is deflected in a predetermined manner by means of the optically effective structures (9). Shaped in the surface of at least one of the surface elements is a diffraction structure which is produced by a superimposition of a linear asymmetrical diffraction grating (24) with a matt structure. The linear asymmetrical diffraction grating (24) has a spatial frequency from the range of values of between 50 lines/mm and 2,000 lines/mm.

Abstract: A security element (2) comprising a plastic laminate has a surface pattern (12) composed mosaic-like from surface elements (13; 14; 15). Shaped into at least two of the surface elements (14; 15) is a respective diffraction structure {B(x, y, T)} produced from a superimposition of a low-frequency grating structure {G(x, y)} with a high-frequency relief structure {R(x, y)}. In the one surface element (14) a grating vector of the grating structure {G(x, y)} and a relief vector of the relief structure {R(x, y)} are parallel and in the other surface element (15) the grating vector (16) and the relief vector (17) include a substantially right angle. In addition the grating vectors (16) of the grating structures {G(x, y)} in the two surface elements (14; 15) are parallel. A common boundary (18) of the two surface elements (14; 15) is visible only upon lighting with linearly polarized light, in daylight both surface elements (14; 15) have the same surface brightness.