Abstract: This invention relates to holograms employing colour addition techniques, and to methods and apparatus for the fabrication of such holograms. The holograms are particularly useful for security applications. A volume reflection hologram storing at least two images, the hologram comprising: a first stored image configured to replay at a first wavelength; a second stored image configured to replay at a second wavelength different to said first wavelength; wherein said first and second images at least partially overlap when replayed together; and wherein said first and second wavelengths are selected such that where said first and second images overlap they give the appearance of a colour defined by a third wavelength different to both said first and second wavelengths.

Abstract: A method and apparatus for inspection of a security article (10) is provided in which a substantially collimated light beam (15) from a point light source (14) is directed onto a diffractive optical projection element (DOE) (11). The light beam is transformed by the DOE (11) into a patterned beam (17) which is reconstructed to form a projected image at a particular position in space remote from the surface of the security article 910). An optical detection device 916) is located at which the patterned beam (17) is reconstructed to detect the projected image. The inspection method and apparatus may be used in equipment for handling, sorting, counting or otherwise processing security articles, in particular security documents such as banknotes. The apparatus may include a processor for generating a signal when the absence or poor quality of a DOE is detected and which is used to isolate or mark the security article.

Abstract: A holographic effect generating structure (HEGS), either stand alone or integrated with a security diffractive image, generates a holographic optically varying image by a process of diffraction of light, this image under white light illumination generates a smoothly and continuously variable structureless optically variable apparent motion effect which moves along a pre-determined track within pre-determined limits, the device characterised that it generates 3 planes of images under white light illumination—an image plane image located at or near the image plane corresponding to the real plane of the device which defines the predetermined movement track of the apparent motion effect and its bounds, a second virtual image plane situated away from the image plane of the device forming a virtual viewing zone corresponding at which an observer would be positioned to observe the visual effect and a third image plane, which defines a region where all the light rays from the image plane artwork to the viewing zone p

Abstract: A medium for preventing forgery having a hologram layer and at least one patterned optically anisotropic layer, wherein the patterned optically anisotropic layer has two or more regions comprising different birefringence property, and wherein all the regions are formed of the same composition.

Abstract: The present invention provides for a data protection device comprising an optically variable diffractive scratch-layered structure overlying data to be protected, wherein the device includes at least first and second opaque metallic layers separated by a flexible light-absorbing separation layer.

Abstract: A multilayer thin film filter is disclosed an organic dielectric layer serving as a spacer layer in a Fabry-Perot structure. The dielectric has embossed regions of varying thicknesses wherein the thickness within a region is substantially uniform. Each different region of a different thickness produces a different color (shift). The size of one of the embossed adjacent regions is such that the color of said one region is uniform and cannot be seen by a human eye as different in color from the uniform color of an adjacent region thereto, and wherein the color within a region can be seen with magnification of at least 10:1. This serves as a covert color coding system useful as a security device.

Abstract: The invention relates to an authenticating medium that comprises a hologram which is used for authentication or other purposes thereby making more complicated appearance and ease of authentication unnecessary. The medium comprises a cholesteric liquid crystal layer (3) on an upper or lower surface of a transparent substrate (2), a hologram-formation layer (4) on a lower surface thereof, and reflective metal layers (5) along the fine relief of the hologram-formation layer (4). The reflective metal layers (5) are formed in a patterned form, as viewed from above, thereby obtaining an authenticating medium (1) capable of solving problems with the prior art. The cholesteric liquid crystal layer may be provided in a double-layer form, and may further have an adhesive layer (7) on the bottom.

Abstract: A method and apparatus for drug product tracking (or other pharmaceutical, health care or cosmetics products, and/or the packages or containers they are supplied with) using diffraction grating-based encoded optical identification elements includes an optical substrate having at least one diffraction grating disposed therein. The encoded element may be used to label any desired item, such as drugs or medicines, or other pharmaceutical or health care products or cosmetics. The label may be used for many different purposes, such as for sorting, tracking, identification, verification, authentication, anti-theft/anti-counterfeit, security/anti-terrorism, or for other purposes.

Abstract: Security element 2, 4 to be embedded in or applied to a security document so that it is visually recognizable from both sides of security document 1 is of multilayer construction and includes interference element I with a color shift effect and diffraction structures 8. Depending on the arrangement of the layers and existing diffraction structures 8 on transparent substrate S the color shift effect and/or the diffractive effects are perceptible from one or both sides of security element 2, 4. The security element is suitable in particular as two-sided windowed thread 4 and as label or transfer element 2 over hole 3.

Abstract: A sensor device comprising a holographic element comprises a grating or hologram recorded in a holographic recording medium wherein at least one physical and/or chemical and/or optical characteristic of the holographic element or the image produced by it varies as a result of variation in relative humidity or moisture content in the air surrounding the element. Also provided is an acrylamide-based photopolymer and an acrylamide-based reflection hologram.

Abstract: An object of the present invention is to provide an electron microscope that employs a hologram of a diffraction pattern to reconstruct a microscopic image involving no imaging aberration due to image forming lenses, as well as a combined illumination lens used for such an electron microscope.

Abstract: A holographic overlay is provided, including: a polycarbonate substrate having a first side and a second side, a diffractive structure cast upon the first side of the polycarbonate substrate, and a reflection-enhancing coating on at least a part of the diffractive structure; wherein the second side of the polycarbonate substrate provides a substantially flat external surface of the overlay capable of fusing to a conforming surface in the presence of heat and pressure without an adhesive. Optionally, the overlay is laser-engraved so as to form ablated voids in the metal coating and carbonize the laser engravable polycarbonate under the ablated voids. According to another aspect of the invention, a metal coating on a hologram is made substantially transparent using a laser to form a transparent portion of a hologram. Optionally, it is done after applying the hologram to an object such as a card, a document, etc., in register with underlying information to ensure its visibility and continuity of the hologram.

Abstract: The present invention provides an optical information reading device includes: a light source that irradiates, with reference beam, a hologram recorded in an optical recording medium; a reading unit that reads information from a holographic image reconstructed by the reference beam being diffracted by the hologram; a housing; a contact member of the housing contacting a paper; an open portion formed in the contact member, through which the optical recording medium is exposed and towards which the reference beam is emitted; an alignment mark formed at a periphery of the open portion, the reference beam irradiating the hologram satisfying a holographic image reconstruction condition by the alignment mark being aligned with an optical recording medium alignment mark recorded on the optical recording medium; and a viewing portion that is positioned in the housing and through which the alignment mark and the optical recording medium alignment mark are visible.

Abstract: A method for printing a binary hologram on a manufactured product comprises the provision of a stamp with a pattern corresponding to the hologram (30). The product is initially coated with a metal layer. The stamp is inked with a masking solution (40) and pressed against the manufactured product (50). Then, the hologram print is obtained by selective etching of parts of the metal layer which are not masked (60). The method is adapted for printing holograms on optical lenses.

Abstract: A microstructure area (201) providing a first diffractive visual effect is produced on the surface layer (240) of a paper or cardboard substrate (230) of a product (200). In addition, a bulge (206) or a recess (207) having a second microstructure area (202) is produced on the surface layer (240), wherein a doubly curved portion (203) is located between the first (201) and the second (202) microstructure areas. Said combination of the bulge (206)/recess (207), microstructure areas (201, 202) and doubly curved portion (203) makes counterfeiting of the product (200) difficult and provides a special visual effect.

Abstract: A hologram substrate includes a hologram section arranged on a surface of the hologram substrate, the hologram section having an uneven pattern configured to form a holographic image, in which the uneven pattern is a depth-modulated pattern and has smooth boundaries between projections and depressions.

Abstract: The present invention relates to a method for the production of polarization holograms, an apparatus for the production of polarization holograms and the use of the polarization holograms according to the invention as data stores, security features or diffractive optical elements for performing conventional optical functions.

Abstract: This invention relates to improved methods of fabricating hologram systems, in particular holograms on a substrate such as a security document or bank note, to hologram systems fabricated by the described methods, and to starting materials for the methods. A method of preparing a hologram on a substrate, the method comprising: providing a hologram recording medium, the material comprising a carrier bearing a photosensitive hologram recording layer; recording a hologram in said photosensitive hologram recording layer; applying an adhesive to said hologram recording layer; attaching said carrier bearing said hologram recording layer to a substrate using said adhesive; and removing said carrier to leave said hologram recording layer attached to said substrate by said adhesive.

Abstract: The present invention relates to a multiple security means comprising at least one interactive security element and at least one further second security element, wherein the interactive security element comprises at least one volume hologram being responsive to at least one applied external stimulus, the use of said security means as well as to products which contain same.

Abstract: A holographic optical element (HOE) that includes a deep image hologram and a method for using this HOE as a security device are described. The deep image hologram is viewable with a collimated or at least partially collimated light source having a center wavelength in the visible region of the electromagnetic spectrum and a spectral bandwidth, wherein the spectral bandwidth of the collimated or at least partially collimated light source at least partially overlaps the spectral bandwidth of the deep image hologram. The deep image hologram is not viewable (i.e., appears essentially unrecognizable to the human eye) with a diffuse lighting source, such as ordinary room lighting.

Abstract: The invention relates to a security-conscious hologram which can apply a sufficient three-dimensional appearance to a reconstructed image in both its vertical and horizontal directions, and which is difficult to illegally copy and easily told from any illegal copy forged from it, and a holographic process of recording it The hologram H2 is of a combined reflection and volume type, wherein a subject image P is recorded, and minute reflection images F and O? from a light source are recorded at least in front of, or in the rear of, the subject image P, both in a reconstructible fashion, and a viewing position E is moved along a hologram surface, so that the subject image P and the minute reflection images F and O? are viewable at varied relative positions.

Abstract: The present invention relates to a security element in the form of a strip. The strip exhibits optical effects which vary, depending on the illumination or viewing direction. The optical effects are provided only in one or more definably delimited, mutually spaced surface regions. The strip outside the visually variable surface regions is transparent or is adapted to the appearance of the surface of the substrate.

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: A digital watermark which is incorporated, perceptibly or imperceptibly, into a diffractive device such as a hologram. When applied to protect and/or authenticate a document of value or a product, the device provides an increased degree of overt and covert security, and permits tracking of the sale, use or other parameters associated with the product and/or document of value.

Abstract: This invention relates to improved techniques for reading holograms, in particular volume reflection holograms, and to improved security documents incorporating volume reflection holograms.

Abstract: The invention provides a process capable of fabricating a cholesteric liquid crystal medium having a volume hologram with efficiency yet without recourse to complicated steps such as an alignment step. This is achievable as follows. A volume hologram layer is formed on a substrate, and a cholesteric liquid crystal layer is then formed on another substrate comprising a center substrate film that is subjected to bondable treatment. The volume hologram layer is applied to the center substrate film that is subjected to bondable treatment, and placed in a state where the volume hologram layer and cholesteric liquid crystal layer are laminated together via the substrate. The substrate is peeled off the volume hologram layer, and an adhesive layer is formed on the surface of the volume hologram layer off which the substrate is peeled off, followed by the provision of the substrate on the adhesive layer.

Abstract: The invention relates to a security-conscious hologram which can apply a sufficient three-dimensional appearance to a reconstructed image in both its vertical and horizontal directions, and which is difficult to illegally copy and easily told from any illegal copy forged from it, and a holographic process of recording it. The hologram H2 is of a combined reflection and volume type, wherein a subject image P is recorded, and minute reflection images F and O? from a light source are recorded at least in front of, or in the rear of, the subject image P, both in a reconstructible fashion, and a viewing position E is moved along a hologram surface, so that the subject image P and the minute reflection images F and O? are viewable at varied relative positions.

Abstract: A method of generating a variable demetallized pattern in a holographic web and a security device using such method. A holographic microstructure pattern is imparted to an oligomer disposed on a surface of a substrate. A metal layer, such as aluminum, is deposited to the holographic microstructure pattern of the substrate and then covered with a variable resist pattern. The variable demetallized pattern in the holographic web is then generated by removing the metal layer not covered by said variable resist pattern.

Abstract: An optical security feature, e.g. for a banknote or other security documents, comprises a first and a second holographic layer arranged on top of each other. Each layer comprises a comparatively simple reflective volume hologram, such as it can e.g. be recorded by the interference pattern of two Gaussian light beams. The volume holograms have different grating spacing and/or orientation as well as different extension such that the observer can distinguish and verify them easily. The simple nature of the holograms make the security feature easy to manufacture, while its two-layer structure makes it hard to copy and yields high diffraction efficiency.

Abstract: A sign comprising at least one support member and a body portion attached to the support member. The sign includes at least one reflective layer secured to the body portion. The sign includes at least one optically transmissive layer secured to the reflective layer such that the reflective layer is positioned between the optically transmissive layer and the body portion. The optically transmissive layer defines an interior portion, a border encompassing the interior portion, and at least one message positioned at least partially within the interior portion. The interior portion and the border comprise contrasting colors. The reflective layer is structured to reflect light through the optically transmissive layer to augment the contrast between the interior portion and the border to thereby enhance the visibility of the message.

Abstract: A multiplexing technique for optical communications used to create a pseudo-random communications signal in the optical domain such that only the sender and/or receiver can decode the signal. The multiplexing technique may include one or more information-bearing optical signals combined with one or more dynamic pseudo-randomly-generated optical signals to create a combined dynamic subcarrier multiplexed privacy-protected output signal. The information-bearing signal is protocol-independent and can be of mixed type, such as RF, analog, and/or digital. Only the receiver of the privacy-protected signal may decode the pseudo-random signal so as to disclose the information-bearing signal. The present invention may use dynamic subcarrier multiplexing selection based on standard digital encryption and the use of optical range time to ensure synchronization.

Abstract: A method for fabricating an optical identification element is provided, wherein a removable plate or substrate having photosensitive material fabricated thereon, one or more gratings are written on the photosensitive material, then lines are etched to create one or more separate optical identification elements. The one or more gratings may be written by exposing the photosensitive material to ultraviolet (UV) light. The lines may be etched to create the one or more separate optical identification elements by photolithography to define/create the same.

Abstract: A surface relief hologram that includes two or more patterns, each pattern being sensitive to different radiation wavelengths. The hologram is made by defining relief features that are sensitive to different wavelengths, and in particular, to one wavelength that is visible to the unaided human eye and to one wavelength that is invisible to the unaided human eye. These relief features of different sensitivities are interspersed over the surface of the substrate in which the hologram is defined. By providing two patterns of different sensitivities, when the hologram is used in a security device, security is improved. Despite this improved security, the hologram can be mass manufactured using known techniques.

Abstract: This invention relates to improved techniques for using holograms to provide security for documents and the like. A method of providing a tamper-resistant pattern in association with a hologram on a substrate, the method comprising: preparing a hologram, said hologram being recorded in a photosensitive recording layer carried by a carrier; printing a pattern onto said photosensitive recording layer; and then attaching said hologram to a substrate by adhesive such that said pattern is between said photosensitive recording layer and said substrate to provide a tamper-resistant pattern in association with said hologram.

Abstract: The main object is to provide a volume hologram transfer foil showing an excellent foil cutting property and capable of being transferred easily to a transferred body. This object is solved by providing a volume hologram transfer foil comprising a substrate, a volume hologram layer formed on the substrate and a heat sensitive adhesive layer formed on the volume hologram layer, wherein the volume hologram layer has a breaking strain at 25° C. in a range of 0.5% to 15% and a breaking strain at 120° C. in a range of 0.5% to 30%, and the heat sensitive adhesive layer has a breaking strain at 25° C. in a range of 0.5% to 15%.

Abstract: A reading apparatus includes an exposure system, a light receiving system, a decoding section and a determination section. The exposure system applies light to a code image printed on a medium. The light has an infrared wavelength and a visible wavelength. The light receiving system receives infrared light and visible light, which are the light reflected on the medium, to capture the code image with the infrared light and capture the code image with the visible light. The decoding section reads a code from the code image captured with the infrared light. The determination section determines authenticity of the medium based on at least the code image captured with the visible light.

Abstract: A security device comprises a holographic or diffractive optically variable effect generating structure which, when viewed normally i.e. perpendicularly to the plane of the device, replays at least one composite image, the composite image being defined by at least a pair of discrete image elements, the structure being such that at least two of the discrete image elements of the composite image have different optimal replay angles.

Abstract: The invention relates to a method of recording machine-readable information on an article, including the steps of: providing a carrier having flakes dispersed therein onto the surface of the article, wherein all of the flakes have a beam-splitting grating pattern encoding the information thereon; aligning the flakes parallel to a sloped plane forming a slope angle with the surface of the article; and, solidifying the carrier. When the article is irradiated with an EM beam, a first portion of the EM beam is reflected from the surface of the article, forming a surface reflection, a second portion of the beam is reflected from the beam-splitting grating pattern, forming an arrangement of sub-beams, and the slope angle provides a spatial separation between the arrangement of sub-beams and the surface reflection, enabling machine-reading.

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 present invention provides for a method of producing an optical device by means of electron beam lithography and including the step of varying the characteristics of the electron beam spot during formation of the device and also an apparatus for producing diffractive optical devices and/or holographic devices by means of electron beam lithography and including an electron beam lithograph, controlling and processing means, means for varying the characteristics of the electron beam spot during formation of the device, and wherein the processing means is arranged for compiling and pre-processing data and for providing optimization and allocation control and to optical devices such as those produced thereby.

Abstract: A holographic sealing member for a container is designed for attachment to the rim of an opening in the container. The holographic sealing member comprises a holographic layer having an upper plastic layer on its upper side and a lower embossed image layer on its lower side. A sealant or adhesive layer is attached to at least those portions of the lower side of the holographic layer that are intended to come into direct contact with the container's rim when the sealing member is placed upon and is sealed to a container. A metal foil layer lies over and covers and is adhesively bonded to the upper side of the holographic layer and may be inductively heated to actuate the heat actuated sealant. A tab covers and is adhesively bonded to the metal foil layer and may be pulled to remove the sealing member from a container.

Abstract: A system and method for encryption of a holographic image is disclosed. The method includes the operation of producing a beam of light having at least two wavelengths of light. The beam of light can be split to form an illumination beam and a reference beam. Amplitude information can be added to the illumination beam with an intensity control device to form an object beam. Wavelength information can be selected in the object beam to form a spatial color modulated object beam. The reference beam and spatial color modulated object beam can be directed to a predetermined location on the holographic media to interfere to record an interference pattern.

Abstract: A method for producing an optical element, preferably a security feature, wherein a film having a first embossed hologram in an embossing layer is provided, and a second embossed hologram is embossed into the same embossing layer such that the first embossed hologram is partly replaced with the second embossed hologram. The invention further relates to a method for producing an optical element wherein an embossable film provided with an embossed hologram is partly filled with printing lacquer, and a method for producing an optical element wherein hologram embossing is prevented by prior partial printing of the embossing film with curable printing lacquer. The invention relates further to optical features producible by the inventive methods, documents of value having an inventive optical feature and a numbering embosser for use in an inventive production method.

Abstract: The invention relates to a method for identifying articles, wherein article identification data are made available and the article is provided with a hologram representing said data so that the article can be identified by way of an intensity profile corresponding to said hologram. To this end, article-identifying individual data are provided, a hologram profile is digitally calculated using said individual data, and an intensity modulation of the hologram-producing beam is determined. The hologram-producing beam transfers the hologram pixels onto a hologram support that is associated with the article to be identified so that the article can be identified by way of the intensity profile reproduced from the associated hologram support.

Abstract: The invention concerns an optically variable element and a security product having such an optically variable element, a foil, in particular an embossing foil or a laminating foil having such an optically variable element, and a process for producing such an optically variable element. The optically variable element has a thin film layer succession with at least one spacer layer for producing color shifts by means of interference. In a first region of the thin film layer succession the spacer layer is of a different layer thickness from in a second region of the thin film layer succession. In that case the layer thicknesses of the spacer layer in the first and second regions are so selected that in the first region of the thin film layer succession a first color shift is produced by means of interference and in the second region of the thin film layer succession a second color shift which is different from the first color shift is produced.

Abstract: The present invention relates to a security display assembly (10; 50) comprising a display (12; 52) for providing a display image and a hologram (14; 54) for providing a holographic image. The hologram is integrated into the display and occupies essentially the same or less area as the display. Integrating the hologram into the display makes counterfeiting of a product provided with the security display assembly more difficult. It also saves space on the product onto which the security display assembly is provided. The invention also relates to a smart card (20) comprising such a security display assembly.

Abstract: The invention relates to a method for forgery-proof labeling of items, such as credit cards, bank notes and the like, comprising the following steps: (a) applying, to a first layer (1) that reflects electromagnetic waves, an inert second layer (3) that is permeable to electromagnetic waves, said second layer having a predetermined thickness, (b) applying, to said second layer (3), a third layer (4) that is formed by metal clusters, and (c) linking the first layer (1) of the label so produced with the item.

Abstract: A discrimination medium 10a includes a first double layered body 101 having a right-handed circular polarization polymer cholesteric liquid crystal layer 11 and a left-handed circular polarization polymer cholesteric liquid crystal layer 12 which are stacked. The right-handed circular polarization polymer cholesteric liquid crystal layer 11 reflects a specific right-handed circular polarization light, and the left-handed circular polarization polymer cholesteric liquid crystal layer 12 reflects a specific left-handed circular polarization light. The discrimination medium 10a is applied to the article 30, and is viewed via a simple determination tool 20 having a filter 21 allowing only right-handed circular polarization light to pass therethough and a filter 22 allowing only left-handed circular polarization light to pass therethough.

Abstract: A breakable seal can be discriminated more easily than the conventional one. The discrimination medium 100 has a cholesteric liquid crystal layer 104, a substrate layer 105, an adhesive layer 102, and a partial peeling layer 103. The discrimination medium 100 has an adhesion strength XA between the adhesive layer 102 and the partial peeling layer 103, an adhesion strength XB between the partial peeling layer 103 and the cholesteric liquid crystal layer 104, and an adhesion strength XC between the cholesteric liquid crystal layer 104 and the substrate layer 105. The relationships XA<XB and XA<XC are satisfied at areas 106, 108, and 110. The relationships XC<XA and XC<XB are satisfied at areas 107 and 109. In the above manner, when the discrimination medium 100 is peeled from the article 101, the discrimination medium 100 is separated into a discrimination medium 116 and a discrimination medium 117.

Abstract: This invention relates to improved holograms, in particular suitable for security applications, and to methods and apparatus for their fabrication. A hologram storing a pair of images, the hologram comprising: a first stored image configured to replay at a first wavelength; and a second stored image configured to replay at a second wavelength different to said first wavelength; and wherein said first and second stored images are spatially complementary such that when replayed they appear together, substantially in register, and give the appearance of a single, substantially uninterrupted image.