Lgz Landis Gyr Zug Ag

Landis & Gyr Betriebs Ag

Gregor Antes

Alex Nyfeler

Walter Trachslin

Peter Gehr

Mathis Halder

David L Greenaway

Ohannes Minnetian

Hansjorg Schmidlin

Martin Stalder

Christian Saxer

Paul Fuchs

A security element for the authentication of a substrate has a pattern comprising optical diffraction elements which are embossed in a carrier material of plastic material and unembossed neutral areas. On the embossing side of the carrier material a reflecting layer covers only surfaces with relief structures of the diffraction elements while the neutral areas which lie between are free of the reflecting layer and are therefore non-reflecting. If the security element is stuck in the form of a stamp onto the substrate and the carrier material is transparent, image portions, which are covered by the stamp, of a feature on the substrate can be discerned through the neutral areas.

Securtiy element

A security element for the authentication of a substrate has a pattern comprising optical diffraction elements which are embossed in a carrier material of plastic material and unembossed neutral areas. On the embossing side of the carrier material a reflecting layer covers only surfaces with relief structures of the diffraction elements while the neutral areas which lie therebetween are free of the reflecting layer and are therefore non-reflecting. If the security element is stuck in the form of a stamp onto the substrate and the carrier metal is transparent, image portions, which are covered by the stamp, of a feature on the substrate can be discerned through the neutral areas.

Security element

A device for embossing a set of motifs having a predetermined motif interval onto a length of film utilizes a rotating embossing cylinder which is provided with a recess for the attachment of an embossing matrix. The embossing matrix has a usable length which is less than the entire circumference of the embossing cylinder but more than 50% of the circumference of the embossing cylinder. A rotating counterpressure cylinder is positioned adjacent the embossing cylinder, such that the film advances between the counterpressure cylinder and the embossing cylinder for embossing said motifs from said embossing matrix onto the film and for defining a free phase during each rotation of the embossing cylinder when the recess is positioned adjacent the film. The device also comprises movement means for providing an additional relative movement between the length of film and the embossing matrix during each free phase of the embossing cylinder. A control mechanism determines the amplitude of the additional relative movement in accordance with the motif interval. It is a significant advantage of the present invention that the embossing cylinder circumference is independent of the motif interval thus allowing for easy change of the embossing matrix.

Device for the embossing of fine structures

A credit document with improved protection against forgery comprises a film which is attached to a local portion of a surface of the credit document. The film includes at least one security mark. The security mark comprises a micro-relief structure for optically diffracting incident light. A protection profile in the form of a macro-relief structure is also embossed into the surface of the credit document. The security mark and the protection profile overlap in part. The relief lines of the protection profile macrostructure are bent away from the plane of the surface of the credit document sufficiently to provide visible gloss effects due to the reflection of incident light. When this arrangement is utilized one or more visible breaks in the security mark occur when the security mark is removed from the credit document. In addition, the security mark is so deformed by the protection profile, that the deformation is easily visible if the security mark is attached to a second (i.e. a forged) credit document.

Arrangement to improve forgery protection of credit documents

An interlaminar sandwich comprises first and second lacquer layers, a diffraction structure embedded between the first and second lacquer layers, a heat activated adhesive layer disposed one one of the lacquer layers, and a transparent stabilization layer disposed over the other lacquer layer, the stabilization layer distributing heat evenly through the interlaminar sandwich so that when heat is applied to the stabilization layer, the adhesive layer will bond the interlaminar sandwich to a substrate. Preferably, the interlaminar sandwich also contains an intermediary layer between the stabilization layer and the first lacquer layer which bonds these layers together. At temperatures below 170.degree. C., the adhesive layer is bonded so intimately to the substrate that the interlaminar sandwich cannot be removed from the substrate without tearing it. At temperatures above 150.degree. C., the lacquer layers soften, thus destroying the diffraction structure. After being built up on a film, the interlaminar sandwich can be punched out in the form of a tag and attached to an identification document thereby protecting the document against attempts to remove the tag.

Interlaminar sandwich with diffraction structure

An article of manufacture contains a substrate which supports a diffraction element divided into surface portions having optically-active microscopic relief structures. At least one pair of surface portions is mirror-symmetric with respect to the orientation of the corresponding relief structures. Each surface portion of the pair has an optically-active, microscopic, asymmetric relief structure defined by an orientation azimuth angle. The azimuth angles are 180.degree. apart. The mirror symmetric pairs constitute optical markings which are machine-readable. The readout device generates an incident light beam and contains photosensors and electronics to output the intensity difference between pairs of diffracted light beams. Alternatively, each surface portion of the diffraction element has a volume hologram rather than a microscopic relief structure for diffracting incident light.

Diffraction element and optical machine-reading device

An article of manufacture contains a substrate which contains a bar code field containing bar elements and background elements. The bar code elements have embossed, optically-reactive, microscopic periodic, relief structures which are suitable for optical-machine readout. A readout device generates an incident light beam and contains photosensors to detect the diffracted light beams.

Bar code field and bar code reader

An article of manufacture including an optically variable surface pattern is disclosed. The optical surface pattern makes visible one out of a plurality of N image representations for each one out of N predetermined viewing directions. The surface pattern comprises M grating elements, each of the grating elements being divided into N grating element sub-portions. Each of the N sub-portions of each grating element contains a diffraction element in the form of a relief structure with predetermined parameters for diffracting incident light. Each of the sub-portions of each grating element thereby corresponds to one pixel of one of the N image representations, so that one of the N image representations is visible from each of said predetermined viewing directions.

Optially variable surface pattern

A document with an embossed macroscopic structure and acting through optical diffraction is disclosed. The structure, which serves as a security element comprises a plurality of surface portions with predetermined relief structures having spatial frequencies of over 10 lines/mm. Each surface portion is different from directly adjoining surface portions and at least some of the surface portions have a maximum dimension of less than 0.3 mm. To the naked eye, the pattern of surface portions on the document appears as a mesh of dots and lines. However, to an examiner with a magnifying device, the dots and lines appear as numbers, characters or other graphic features.

Document with an optical diffraction safety element

A method and apparatus for embossing a pattern having a microscopic relief structure, such as, for example, an optical diffraction grating, onto a layer of thermoplastic material is disclosed. A small circular region of a flexible embossing die is pressed against the thermoplastic layer by means of a punch. A fraction of the corresponding small circular region of the thermoplastic layer is then heated from the rear by a beam of radiant energy. The process may be repeated at all points on the thermoplastic layer where the pattern is desired.

Method and apparatus for producing a relief pattern with a microscopic

In a system for optical display and photo-electric scanning of the contents of a counter equipped with counting wheels, and wherein each counting wheel includes a plurality of numeral members visually distinguishable from the periphery thereof, a coded optical marking member is associated with each numeral member of a respective counting wheel. The coded optical marking member includes at least one optical surface element, and the optical marking members of the counting wheels extend along respective rows, and may be scanned by a light ray moving along a corresponding row. The improvement includes one of the members being superimposed at least in part onto another of the members in a corresponding row, and being partially light-transmitting, while each optical surface element is light-reflective, so that the numeral members are visible upon being illuminated with diffuse light, but wherein a light ray directed onto a respective optical surface element is reflected therefrom.

System for the display and scanning of the contents of a counter

A document includes a substrate which has an outer surface and defines a plane, and a coordinate system which is defined with respect to the plane. A diffraction-optical authenticating element covers at least part of the outer surface, and generates at least one color pattern constituting a visually testable feature which verifies the authenticity of the document. The diffraction-optical authenticating element provides a color pattern moving at a predetermined velocity along a predetermined track when the document is illuminated from a first direction and viewed from a second direction, as defined with respect to the coordinate system, upon the document being rotated within the plane along a prearranged sense of rotation, and at a prearranged velocity.

Document having an optical-diffraction authenticating element

An apparatus for embossing a high resolution relief pattern such as a phase hologram or diffraction grating from a mold onto a thermoplastic material is disclosed. The apparatus comprises first and second adjacent disks adapted to rotate in opposite senses, the disks serving to define an embossing zone therebetween in which the circumferences of the disks exert pressure on one another. The first disk serves to transport the thermoplastic material to the embossing zone. To preheat the thermoplastic material, a preheating band of limited length is mounted under tension on the circumference of the first disk, the preheating band being resistively heated by a longitudinally flowing electric current. A resistively heated band-shaped embossing mold is mounted on the circumference of the second disk. The embossing mold and the thermoplastic carrier come into contact with one another in the embossing zone. The pressure exerted by the disks on one another in the embossing zone is sufficient to transfer the relief pattern from the heated mold to the heated thermoplastic material. A mechanism for controlling the embossing pressure is provided.

Apparatus for embossing high resolution relief patterns

In an apparatus and a method for examining the authenticity of a document, which includes at least a machine-readable authenticity feature in the form of an optical microstructure for diffracting at least one component of a beam of light rays which has a wavelength of a first predetermined value and impinges on the microstructures along a predetermined direction, a light source for emitting the beam of light rays, and wherein the components of the light rays diffracted from the microstructure have an intensity distribution defining an effective center line of 'gravity' along one direction of diffraction, a light-sensing device for sensing the light rays diffracted from the microstructure and for generating electrical signals from the sensed light rays, and an evaluator for processing the electrical signals generated by the light sensor, and for deriving from information contained in the processed electrical signals a YES/NO decision whether the document is authentic or not, there is provided a control connected to the light source so that the light source switches the wavelength of the beam of light rays from the first predetermined value to a second predetermined value, and wherein the evaluator provides the YES decision if the shift between the center lines of gravity of the intensity distribution of the components of the light rays diffracted by the microstructure lies between predetermined limits.

Apparatus and a method for testing the authenticity of documents

In a security blank which includes a substrate which has two major surfaces, a thermoplastic layer which has a predetermined refraction index and is suitable for embossing thereon a machine-readable authenticity feature in the form of an optical microstructure, and a transparent layer which has a prearranged refraction index for covering and protecting the microstructure, and wherein the prearranged refraction index has a value different from the predetermined refraction index, and the microstructure generates a characteristic diffraction effect from light incident thereonto, the improvement includes a surface of the substrate facing the thermoplastic layer, which has within a region of the microstructure diffuse reflection characteristics of a predetermined magnitude, and wherein the thermoplastic layer is transparent, and wherein the difference between the refraction indexes is sufficiently small, and the magnitude of the diffuse reflection characteristics is sufficiently large, so that the characteristic diffraction effect of the microstructure is not normally detectable by the eye of an observer.

Growing community of inventors

Zurich, Switzerland

Gregor Antes