• 专利附录
  • 专利说明
  • 权利要求
  • 类似技术
  • 同族专利
  • 引用文献
  • 法律状态
  • 优先权
    • 专利摘要:
    An optical device, preferably a security device for a security document, comprising a substrate having a first side and a second side, an array of microlenses located on the first side, and an array of microimages such that the microimages are viewable by the microlenses or wherein the arrangement of micro-images includes first and second micro-images, wherein the first micro-lenses and the first micro-images are configured to provide a first visual effect, and wherein the second micro-lenses and the second micro-images are configured to provide a second visual effect, and wherein the first microlenses have a different height with respect to the substrate than the second microlenses.
    公开号:AT519179A2
    申请号:T9204/2016
    申请日:2016-05-20
    公开日:2018-04-15
    发明作者:Fairless Power Gary
    申请人:Ccl Secure Pty Ltd；
    IPC主号:
    专利说明:

    (57) An optical device, preferably a security device for a security document, including a substrate having a first side and a second side, an array of microlenses located on the first side, and an array of microimages so that the microimages pass through the Microlenses are viewable or can be made viewable, wherein the array of microlenses includes first and second microlenses, and wherein the array of microimages includes first and second microimages, wherein the first microlenses and the first microimages are configured to provide a first visual effect, and wherein second microlenses and the second microimages are configured to provide a second visual effect, and wherein the first microlenses are different in height from the substrate than the second microlenses.
    DVR 0078018
    ♦ · ♦ · ·· • · • · · • · · · • • · ·· · · • · · « ··· • • · · • · · ·• · · · • ·• · •• • ··· ** ·· ·· ···· · * · 36
    Summary:
    An optical device, preferably a security device for a security document, comprising a substrate with a first side and a second side, an arrangement of microlenses, which are located on the first side, and an arrangement of microimages, so that the microimages can be viewed through the microlenses or can be made viewable, wherein the array of microlenses includes first and second microlenses, and wherein the array of microimages includes first and second microimages, wherein the first microlenses and the first microimages are configured to provide a first visual effect, and wherein the second microlenses and the second microimages are configured to provide a second visual effect, and wherein the first microlenses are different in height from the substrate than the second microlenses.
    Fig. 2/46
    Field of the Invention
    The invention relates generally to the field of optical devices that produce optically variable visual effects, such as document security devices.
    Background of the Invention
    Optical devices based on microlenses are known to provide increased security against counterfeiting. Such devices are typically molded or attached to a document requiring protection against counterfeiting, for example a banknote. The general operational principle of the microlens device is that an array (which can be a one or two dimensional array) of microlenses is configured to view a printed pattern, usually an array of microimages (i.e., small images). The microlenses focus on the micro images to provide a visual effect, which is typically an optically variable effect.
    Two effects are particularly known which use such microlens arrangements. The first is an integral image effect in which there is a micro image for each microlens, and when the viewing angle changes, different portions of the micro image become visible through the lens. This arrangement enables the display of a three-dimensional image and / or a three-dimensional animation. The second is the so-called moiré magnification, where the space between adjacent microlenses is somewhat different than the space between adjacent microimages and / or the two matrices are rotated slightly in relation to one another. The effect is that enlarged versions of the micro images are visible through the lenses, which appears to be moving and / or rotating and / or changing size when the viewing angle is changed. Typically, the micro images of an integral image vary, whereas the micro images of a Moire image are identical, although variations of these arrangements are known in the art.
    In general, it is not the case that the same microlenses are optimal in providing two different visual effects, and the designers of such optical devices determine the optimal microlenses to use as needed.
    Summary of the invention
    The inventors have recognized that there are advantages to counterfeiting prevention that are obtained by combining two different microlens devices in one. In order to improve the visual effect of the composite device, different configurations of microlenses should be integrated into the microlens array, each configuration being tailored to the associated type of device.
    For this reason, according to one aspect of the present invention, there is provided an optical device, preferably a security device for a security document, comprising a substrate with a first side and a second side, an arrangement of microlenses located on the first side, and an arrangement of micro images so that the micro images can be viewed or can be made viewable through the microlenses,
    3/46 wherein the arrangement of microlenses includes first and second microlenses and wherein the arrangement of microimages includes first and second microimages, wherein the first microlenses and the first microimages for
    Are configured to provide a first visual effect and the second microlenses and the second microimages are configured to provide a second visual effect, the first visual effect being a visual effect through moiré magnification and the second visual effect being a visual effect through integral images , and wherein the first microlenses have a different height with respect to the substrate than the second microlenses.
    Typically, the first visual effect and the second visual effect are distinguished by different optimal microlens heights. The first visual effect and the second visual effect are preferably distinguished on the basis of an optimal selection of at least one of the following: deflection; Floor space; Basic form; F-number; and focal length. In this case, the first and second microlenses may include different values for at least one of the following: deflection; Base area, basic shape, F number; and focal length.
    The arrangement of microimages is optionally located on the second side opposite the arrangement of microlenses, so that the microlenses and microimages are in a fixed relationship. Alternatively, the arrangement of microimages can be on the first or second side, so that the microlenses and microimages must be brought into an overlapping arrangement in order to view the microimages through the microlenses.
    4/46
    In one embodiment, the first and second microlenses are located on raster positions of a conventional microlens raster. In another embodiment, the first and second micro images are on raster positions of a conventional micro image raster. Optionally, at least in this case, the first and second micro images are identical.
    According to a second aspect of the present invention, there is provided an optical device, preferably a security device for a security document, comprising a substrate with a first side and a second side, an arrangement of microlenses located on the first side, and an arrangement of microimages located either on the first side or a second side of the substrate in a non-overlapping relationship or on another substrate of the microimages, the array of microlenses including first and second microlenses, and the array of microimages first and second Includes micro-images, wherein the first microlenses and the first micro-images are configured to provide a first visual effect, and wherein the second microlenses and the second micro-images are configured to provide a second visual effect, and so that the optical device can do so is configured to provide the first visual effect and the second visual effect when the array of microimages and the array of microlenses are brought into an overlapping configuration.
    The first microlenses preferably have a different height with respect to the substrate than the second microlenses and / or contain different values for at least one of
    5/46
    The following: deflection; Floor space; Basic form; F-number;
    and / or focal length.
    In one embodiment of an aspect, the first visual effect is a visual effect through moiré magnification and the second visual effect is a visual effect through integral images. Optionally, one of the first and second microlenses is configured for focused viewing of their associated microimages and the other of the first and second microlenses is configured for defocused viewing of their associated microimages. The microimages configured for defocused viewing can be configured to provide a visual effect by changing contrast. The first and second microimages are preferably located on essentially the same level. For example, the first and second microimages can be formed in the same document using a common printing element.
    In one aspect, both of the first and second microlens grids and / or both of the first and second microimage grids can be square or rectangular grids. Alternatively, the first and second microlens grids and / or the first and second micrograph grids are selected from one of the five two-dimensional Bravais gratings. In addition, the first and second micro images are optionally positioned according to the positions of the corresponding first and second micro image masks. The first and second microlenses can be positioned according to the locations of the corresponding first and second microlens masks, each first microlens preferably being only present where the entire first microlens is positioned within a corresponding first microlens mask. Alternatively, each
    6/46 second microlens can only be present where the entire second microlens is positioned within a corresponding second microlens mask.
    Typically, in one aspect, the microlenses are formed from an embossed and cured curable ink, preferably a radiation curable ink.
    Optionally, the optical device further includes alignment means for guiding a user, such as to achieve correct, or substantially correct, relative angular alignment between the array of microlenses and the array of microimages.
    According to a further aspect of the present invention, a document is provided, preferably a security document and even more preferably a banknote, which contains an optical device according to one of the first two aspects.
    The document optionally has a substantially transparent document substrate, a portion of which corresponds to the substrate of the optical device. Alternatively, the document can have a substantially opaque document substrate, the optical device either being attached to a surface of the document substrate and / or positioned within a cut-out region of the document substrate.
    According to another aspect of the present invention, there is provided a method of manufacturing the optical device of the first two aspects, comprising the steps of: applying radiation curable ink to a first side of a transparent substrate; Embossing and
    7/46
    Curing the radiation-curable ink, thereby forming the
    Arrangement of microlenses; and printing the array of
    Micro images on either the first page or the second
    Page.
    The arrangement of microlenses preferably coincides with the arrangement of microimages which is positioned on the second side of the substrate opposite the microlenses.
    Typically, the step of embossing the array of microlenses and the step of printing the microimages are performed simultaneously or substantially simultaneously. In addition, the first and second micro images are preferably printed in the same publication.
    Optionally, the substrate corresponds to a region of a larger document substrate.
    Security document or token
    As used herein, the term security documents and tokens includes all types of documents and tokens of value and identification documents, including but not limited to the following: currency elements such as banknotes and coins, credit cards, passports, ID cards, securities and share certificates, driver's licenses, title deeds, travel documents such as flight and train tickets, entrance tickets and tickets, birth, death and marriage certificates and academic transcripts.
    The invention is particularly, but not exclusively, applicable to security documents or tokens such as banknotes or identification documents such as ID cards or passports, which are formed from a substrate onto which one or more printing layers are applied. The diffraction gratings and optically variable devices described here can also be used in other products such as packaging.
    Security device or feature
    As used herein, the term security device or feature includes any of a large number of security devices, elements or features that are intended to protect the security document or token from being tampered with, copied, modified, or tampered with. Security devices or features can be provided in or on the substrate of the security document or in or on one or more layers applied to the base substrate and can take a wide variety of forms, such as security threads embedded in layers of the security document are; Security inks such as fluorescent, luminescent and phosphorescent inks, metallic inks, iridescent inks, photochromic, thermochromic, hydrochromic or piezochrome inks; printed and embossed features, including relief structures; Interference layers;
    Liquid crystal devices; Lenses and lenticular structures; optically variable devices (OVD) such as diffractive devices, including diffraction gratings, holograms and diffractive optical elements (DOE).
    substratum
    In the sense used here, the term substrate refers to the starting material from which the security document or token is formed. The starting material can be paper or another fiber material such as cellulose, a plastic or a polymer material,
    9/46 including, among others, polypropylene (PP), polyethylene (PE), polycarbonate (PC), polyvinyl chloride (PVC), polyethylene terephthalate (PET), biaxially oriented polypropylene (BOPP); or a composite material of two or more materials, such as a laminate of paper and at least one plastic material or of two or more polymer materials.
    Transparent windows and half windows
    In the sense used here, the term window refers to a transparent or translucent area in the security document in comparison to the essentially opaque region to which a print is applied. The window can be completely transparent so that it allows the transmission of light to be substantially unaffected, or it can be partially transparent or translucent, allowing the transmission of light in part without allowing objects to be clearly seen through the window area are.
    A window area may be formed in a polymeric security document that has at least one layer of transparent polymeric material and one or more opacifying layers applied to at least one side of a transparent polymeric substrate by omitting at least one opacifying layer in the region that forms the window area. If opacifying layers are applied to both sides of a transparent substrate, a completely transparent window can be formed by omitting the opacifying layers on both sides of the transparent substrate in the window area.
    / 46
    • · • · · ”
    A partially transparent or translucent area, hereinafter referred to as a "half window," can be formed in a polymeric security document that has opacifying layers on both sides by omitting the opacifying layers on only one side of the security document in the window area, so that the "half window is not completely transparent, but does allow some of the light to pass through without allowing objects to be clearly seen through the half window.
    Alternatively, it is possible for the substrates to be formed from an essentially opaque material such as paper or fiber material, an insert made of transparent plastic material being inserted into a cutout or a cutout in the paper or fiber substrate in order to provide a transparent window or translucent material Train half-window area.
    Cloudy layers
    One or more opacifying layers can be applied to a transparent substrate to increase the opacity of the security document. An opacifying layer is such that L T <L o , where L o is the amount of light that is incident on the document and L T is the amount of light that is transmitted through the document. An opacifying layer can comprise any one or more of a variety of opacifying coatings. For example, the opacifying coatings can comprise a pigment, such as titanium dioxide, dispersed in a binder or carrier of a heat-activated crosslinkable polymer material. Alternatively, a substrate made of transparent plastic material could be arranged between opaque layers of paper or another / partially or essentially opaque material, to which information can subsequently be printed or otherwise applied.
    Refractive index n
    The refractive index of a medium n is the ratio of the speed of light in a vacuum to the speed of light in the medium. The refractive index n of a lens determines the amount in which light rays reaching the lens surface are refracted, according to Snellius' law of refraction:
    * Sin (cx) = 77 * Sin (fF) where a is the angle between the incident beam and the normal beam at the point of incidence on the lens surface, q is the angle between the refracted beam and the normal beam at the point of incidence , and ni is the refractive index of air (a value of 1 can be taken as an approximation for ni).
    Embossable radiation curable ink
    The term embossable radiation curable ink used here refers to any ink, varnish or other coating which can be applied to the substrate in a printing process and which can be embossed while it is being used it is soft to form a relief structure and can be hardened to fix the embossed relief structure. The curing process does not take place before the radiation-curable ink is embossed, but it is possible that the curing process occurs either after the embossing or at substantially the same time as the embossing step. The radiation curable ink is
    12/46
    preferably curable by ultraviolet (UV) radiation.
    Alternatively, the radiation curable ink can be replaced by others
    Forms of radiation, such as electron beams or
    X-rays to be hardened.
    The radiation curable ink is preferably a transparent or translucent ink formed from a clear resin material. Such a transparent or translucent ink is particularly suitable for printing translucent security elements such as sub-wavelength gratings, transmissive diffractive gratings and lens structures.
    In a particularly preferred embodiment, the transparent or translucent ink preferably comprises a UV-curable, clear, embossable, acrylic-based lacquer or such a coating.
    Such UV curable varnishes can be obtained from various manufacturers, including Kingfisher Ink Limited, product Ultraviolet Type UVF-203 or the like. Alternatively, the radiation-curable embossable coatings can be applied to other compounds, e.g. B. nitrocellulose based.
    It has been found that the radiation-curable inks and lacquers used here are particularly suitable for embossing microstructures, including diffractive structures such as diffraction gratings and holograms and microlenses and lens arrays. However, they can also be embossed with larger relief structures, such as non-diffractive optically variable devices.
    / 46
    The ink is preferably embossed and cured by ultraviolet (UV) radiation at substantially the same time. In a particularly preferred embodiment, the radiation-curable ink is applied and embossed at substantially the same time in a gravure printing process.
    Preferably, in order to be suitable for gravure printing, the radiation curable ink has a viscosity that is substantially in the range from about 20 to about 175 centipoise, more preferably from about 30 to about 150 centipoise. The viscosity can be determined by measuring the time for the paint to drain from a No. 2 Zahn cup. A sample that is drained in 20 seconds has a viscosity of 30 centipoise and a sample that is drained in 63 seconds has a viscosity of 150 centipoise.
    For some polymer substrates, it may be necessary to apply an intermediate layer to the substrate before the radiation curable ink is applied to improve the adhesion of the embossed structure which is formed on the substrate using the ink. The intermediate layer preferably comprises an undercoat layer, and more preferably the undercoat layer includes a polyethyleneimine. The undercoat layer may also include a crosslinking agent, for example a multifunctional isocyanate. Examples of other primers suitable for use in the invention include: hydroxyl-terminated polymers; hydroxyl-terminated copolymers based on polyester; crosslinked or uncrosslinked hydroxylated acrylates; polyurethanes; and UV curing anionic or cationic acrylates. Examples of suitable crosslinking agents include: isocyanates;
    14/46 • · • · ·· • · · • · · ·
    polyaziridines; zirconium; aluminum acetylacetone;
    Melamine; and carbodiimides.
    Metallic nanoparticle ink
    As used herein, the term metallic nanoparticle ink refers to metallic particle ink with an average size of less than one micron.
    BRIEF DESCRIPTION OF THE DRAWINGS
    Embodiments of the invention will now be described with reference to the accompanying drawings. It is understood that the embodiments are presented for illustration only and the invention is not limited by this illustration. The following applies to the drawings:
    Figures la-lc show documents that incorporate optical devices in accordance with various embodiments;
    FIG. 2 shows an optical device with an arrangement of microlenses with different heights;
    Figure 3 shows two sets of microimages, one suitable for use as a moiré magnification and the other suitable for providing an integral image;
    Figures 4a and 4b show two different arrangements of the microlenses;
    FIG. 4c shows microimages which are optionally positioned under the first and second microlenses;
    15/46 • ·
    FIG. 5a shows two micro-image grids which are positioned on a common micro-image raster;
    FIGS. 5b and 5c show two microlens grids with different gaps;
    FIG. 5d shows the positioning of the first and second microlenses according to one embodiment;
    Figures 6a and 6b show self-test arrangements;
    Figures 6c and 6d show test arrangements;
    FIG. 7 shows two exemplary micro image grids for use in test arrangements; and
    Figure 8 shows a protective layer covering the microlenses.
    Description of preferred embodiments
    Figures la-lc each show a document 2 with an optical device 4 according to embodiments of the invention. The optical device 4 comprises a transparent (or at least substantially transparent) substrate 8. The document 2 also comprises a substrate (herein document substrate 9). In the embodiment from FIG. 1 a, the two substrates 8, 9 are the same, that is to say that the optical device 4 and the document 2 share the same substrate 8, 9. In the embodiment from FIG. 1b, the document substrate 9 differs from the substrate 8 of the optical device 4.
    16/46 • ······ · · • · · · · * · «,
    In any case, document 2 contains first and second opacifying layers 7a, 7b. The opacifying layers 7a, 7b act to reduce or eliminate the transparency of the document 2 in the areas in which the layers 7a, 7b are present. In the embodiments shown in FIGS. 1 a and 1 b, both opacifying layers 7 a, 7 b are not present in the region of the optical device 4, which causes the optical device 4 to be located within a window region of the document 2. In the embodiment from FIG. 1c, the device is located in a half window region, the second opacifying layer 7b completely covering the optical device 4, as shown, but the first opacifying layer 7a is not present in the region of the optical device 4.
    It is also possible that the document 2 is inherently opaque (or substantially opaque), for example where the document substrate 9 is paper or a paper composite. In this case, separate opacifying layers 7a, 7b are not necessarily required. In this case, the optical device 4 can still be located in a window region of the document 2, which can be achieved using known methods, such as, for example, shaping the optical device 4 as a film and applying the film to a cut-out area of the opaque document substrate 9. Otherwise, the optical device 4 is typically attached to the document substrate 9, for example by hot stamping.
    The optical device 4 typically provides a security function, that is to say that the optical device 4 acts to reduce the susceptibility of the document 2 to forgery. The optical device 4 can be used as a "security device or a" security token
    17/46
    when used for this purpose.
    A document 2 that requires protection against counterfeiting is often referred to as a “security document.
    FIGS. 1 a to 1 c also show further security features 6 (6 a in FIG. 1 a, 6 b in FIG. 1 b, 6 c in FIG. 1 c) which can assist in reducing the susceptibility of document 2 to forgery in combination with the optical device 4. In Figure la, the additional security feature 6a is implemented in a window region of the document 2, with the additional security feature 6b being implemented in an opaque (i.e. non-windowed) region of the document 2 in Figure 1b. FIG. 1 c shows the further security feature 6 c that is implemented within a half window region of document 2. The illustrated arrangements are merely examples and, in general, document 2 may include one or more security features 6, each implemented in a window, half window, or opaque region of document 2. Exemplary additional security features 6 include: optically variable devices such as diffractive optical elements, Kinograms®, microlens-based features, holograms, etc .; Watermark images, small print, etc.
    Referring to Figure 2, an optical device 4 according to one embodiment is shown. The optical device 4 includes a microlens layer 10, including microlenses 16, which can be formed on a first side 14a of the substrate 8 by an embossing process using a radiation-curable ink, as disclosed, for example, in the applicant's PCT publication WO 2008/031170. The microlens layer 10 includes first microlenses 16a with a first height and
    18/46
    ·· ·· ·· • · • · • · • ♦ · • · • * ··· • • · • · • · • • · • · • · • ·· • · • · * ·· ·
    second microlenses 16b with a second height that differs from the first height.
    A microimage layer 12 is located on a second side 14b of the substrate 8 opposite the microlens layer 10. The microimage layer 12 comprises an arrangement of microimages 18, comprising first microimages 18a and second microimages 18b. Typically, the first and second microimages 18a, 18b lie on the surface of the second side 14b of the substrate and therefore they are on the same plane. The microimage layer 12 may be formed on the second side 14b by printing an ink, embossing, laser engraving, or any other suitable image forming process. The first microimages 18a may be the same or different in appearance than the second microimages 18b.
    With reference to FIG. 3, the first and second microimages 18a, 18b are each arranged according to a regular microimage grid 20 (first microimage grid 20a and second microimage grid 20b). For the purpose of FIG. 3, the first and second micro images 18a, 18b differ. The micro image grids 20a, 20b are typically of the same type, for example both rectangular grids, as shown. In general, the micrographs 20 can be of any suitable repetitive type, for example one of the five Bravais gratings.
    The first microlenses 16a and the first microimages 18a are configured to provide a first visual effect, whereas the second microlenses 16b and second microimages 18b are configured to provide a second visual effect. Generally the first and second
    19/46 differentiate visual effect according to embodiments in that the first and second microlenses 16a, 16b have different optimal heights for generating the corresponding visual effect.
    ····
    In the particular embodiment described, the first visual effect is a moire magnification visual effect and the second visual effect is an integral image visual effect. The first microlenses 16a are optimized to provide the visual effect by moiré magnification, at least by selecting the associated first height. Similarly, the second microlenses 16b are optimized for providing the visual effect through integral images, at least by selecting the associated second height, which differs from the first height.
    Other parameters, as well as or instead of the height, may be different between the first and second microlenses 16a, 16b to optimize each arrangement for the intended purpose. Such parameters include: deflection; Floor space; Basic form; F-number; and / or focal length. If the base areas of the first and second microlenses 16a, 16b differ, it may be necessary to include a gap between some or all of the adjacent microlenses 16.
    In general, an integral image can provide a relatively complicated optically variable effect (as well as relatively simple effects). A "change in contrast, as used herein, is a relatively simple optically variable effect that can be viewed as a special case of an integral image. The change in contrast simply changes from one color to another when the viewing angle is changed, using identical microimages. The
    20/46
    For the sake of illustration, the second micro images 18b shown are suitable for generating a contrast change, although it is understood that they are can instead be configured according to a more general integral image.
    It is contemplated that one of the first and second microlenses 16a, 16b be implemented with a focal length configured to match the position of the corresponding microimages 18a, 18b ("focused configuration"), whereas the other of the first and second microlenses 16a , 16b is implemented with a focal length that is configured not to match the position of the corresponding microimages 18a, 18b (“defocused configuration). Such a “defocused configuration is described in WO 2010/099571 A1. This can find particular application when the contrast change embodiment described above is implemented.
    According to one embodiment, as shown in FIGS. 4a to 4c, the first and second microlenses 16a, 16b are arranged according to a common microlens array 22. In the implementation from FIG. 4a, the first and second microlenses 16a, 16b are arranged in alternating rows. In the implementation from FIG. 4b, the first and second microlenses 16a, 16b are arranged alternately in both directions (that is, from left to right and from top to bottom). It goes without saying that a number of different arrangements can be used, for example similar microlenses 16 can be arranged in groups (for example in groups of four). In the figures, the type of microlenses 16a, 16b is indicated by the shading in and around the circle, which represents microlens 16a, 16b, as indicated in the figures.
    21/46 ·· ·· ·· ·· · · · • ·· ·· · · ·. , ,
    • ·· · ···. , , ; ······. ,
    The square outlines in Figures 4a and 4b are associated with each microimage 16 and represent masks 24. The purpose of these is to define where the first microimages 18a and second microimages 18b should be printed on the second page 14b and they are therefore useful in the design of the first and second micro image grids 20a, 20b.
    This ensures that each microimage 18 can be viewed through the correct type of microlens 16 (i.e., each first microimage 18a and through a first microlens 16a), and every second microimage 18b and through a second microlens 16b, as in Figure 4c shown). Although the masks 24 are shown with gaps between them in the figures, this is not necessary and they can instead touch adjacent masks 24. In addition, the bases of the microlenses 16 are not required to contact the sides of the masks 24. In general, the masks are required to fully contain their associated microlens 16. It should be noted that masks 24 are actually not printed on second page 14b and are only a convenient technique for providing the final pattern for printing.
    Referring to Figure 4c, the effect of masks 24 is shown; the first microimages 18a are printed only within the masks 24 associated with the first microlenses 16a and the second microimages 18b are printed only within the masks 24 associated with the second microlenses 16b. For the sake of clarity, the shading of the masks 24 from FIGS. 4a and 4b is not shown.
    Another embodiment is shown in FIGS. 5a to 5d. Here, the first and second microimages 18a, 18b are arranged according to a common microimage grid 26 (see
    22/46 • ·
    Figure 5a). The first and second visual effects are distinguished in that they require different microlens gaps and are optionally optimized according to different microlens heights and / or one or more other microlens parameters. In the specific embodiment described, the first visual effect is a visual effect through moiré magnification and the second visual effect is a visual effect through integral images. In order to enable both a visual effect through integral images and a visual effect through moire magnification, it is necessary that the first and second microlenses 16a, 16b are not positioned on the common microlens grid 22 described above and instead are on grid positions of a first microlens grid 22a ( see Figure 5b) or a second microlens grid 22b (see Figure 5c) are positioned.
    “Gap is used herein to describe the space of an array of microlenses 16. For example, the gap may correspond to the center-to-center distance between adjacent microlenses 16 within the array. Typically, the space between adjacent microlenses 16 includes a diameter of microlens 16 and any gap that is provided between adjacent microlenses 16.
    The first and second microlens grids 22a, 22b are distinguished by one or both of the grid spacing and grid alignment. Without further consideration, the positioning of the microlenses 16 on the relevant one
    Grid positions cause the microlenses 16 to overlap one another. To take this into account
    Microlens masks 28a, 28b are used. In one implementation
    23/46
    (not shown), the microlenses 16 are simply optionally under their associated microlens mask 28a,
    28b, which may result in the microlenses being partially molded.
    However, the microlens masks 28a, 28b in the implementation shown in FIG. 5d are configured to ensure that microlenses 16 are not partially shaped. To accomplish this, at least the first microlens masks 28a must have an area larger than that associated with the first microlenses 16a, each first microlens mask 28a typically having dimensions that are twice the space between adjacent first microlenses 16a ( 5d, the dimensions of the first microlens masks 28a are exactly twice the space between the first microlenses 16a). Instead of simply forming each first microlens 16a within an associated first microlens mask 28a, which can lead to partial lens formation, only first microlenses 16a that are completely present within an associated first microlens mask 28a are formed. This leads to a lower density of first microlenses 16a on the first side 14a.
    In FIG. 5d, the second microlens masks 28b have an integer multiple of the spacing between adjacent second microlenses 16b by dimensions (the multiple being two in the case). This is not necessarily necessary and in general the second microlens masks 28b should have dimensions at least a multiple of two larger than the space between adjacent second microlenses 16b. In this more general case, the same rule applies to the second
    24/46
    Microlenses 16b; d. that is, only complete second microlenses 16b are formed. It is possible for the first microlens masks 28a dimensions to have an integer multiple of the space between adjacent first microlenses 16a. In a particular embodiment, the dimensions of both first and second microlens masks 28a, 28b are selected to be integer multiples of the space between their corresponding microlenses 16a, 16b.
    According to one implementation, the second microlens masks 28b have the same size as the first microlens masks 28a (for example as shown in FIG. 5d). Another implementation, not shown, has different mask sizes for the first microlens masks 28a and the second microlens masks 28b. If the second microlens masks 28b have dimensions that are not equal to an integer multiple of the diameter of the second microlenses 16b, it is typically desirable to add only the full second microlenses 16b in a manner similar to that described with respect to the first microlenses 16a to form.
    Another embodiment shown in Figures 6a to 6c can be considered a variation of the embodiment of Figures 5a to 5c. In this embodiment, the micro images 18 are not printed directly opposite the microlenses 16. Instead, the microimages 18 are positioned elsewhere on the document 2, or alternatively the microimages 18 and microlenses 16 are positioned on different substrates (one of the microlenses 16 and microimages 18 being present on the document 2). To view the optical effect, the micro images 18 in
    25/46
    be brought to a position where the micro images 18 through the
    Microlenses 16 can be viewed. If both the microlenses and the microimages 18 are positioned on the same document 2, this can be referred to as a “self-checking arrangement.
    The implementation of FIG. 6a shows the microimages 18 which are printed on the first page 14a in a different area of the document 2 than the microlenses 16. Figure 5a also shows document 2 folded to view the visual effect, that is, so that the micro images 18 can be viewed through the microlenses 16a. The implementation of FIG. 6b shows the microlenses 16 which are formed on the first page 14a and the microimages 18 which are printed on the second page 14b in a different area of the document 2 than the microlenses 16. Figure 6b also shows document 2 folded to view the visual effect, that is, so that the micro images 18 can be viewed through the microlenses 16a. Figures 6a and 6b show self-test arrangements. As can be seen, the focal length of the microlenses 16 must be selected based on either the thickness of the document substrate 9 in the case of Figure 6a or twice the thickness of the document substrate 9 in the case of Figure 6b.
    Figures 6c and 6d, on the other hand, show document 2 and a separate checking element 32 (32a in Figure 6c, 32b in Figure 6d). In FIG. 6c, the microlenses 16 are positioned as a feature of the test element 32a, which contains a transparent test substrate 34a. To view the visual effect, the inspection element 32a, as shown, is arranged such that the microimages 18, which are positioned on the document 2, through the microlenses 16 of the
    26/46 ·· ·· ··
    Examination element 32a can be viewed. Figure 6d shows the alternative situation where it is the microimages 18 that are positioned as a feature of the test element 32b. In this case, the test substrate 34b may be transparent, translucent, or opaque as desired. In order to observe the visual effect, the inspection element 32a, as shown, is arranged such that the micro images 18 of the inspection element 32b can be viewed through the microlenses 16, which are positioned on the document 2.
    The embodiment of Figures 6a through 6d cannot rely on the coverage between the printed microimages 18 and the shaped microlenses 16 to ensure that the first microimages 18a are positioned for viewing by first microlenses 16a and the second microimages 18b for viewing by second ones Microlenses 16b are positioned.
    In order to enable the viewing of the two different visual effects, the first and second micro images 18 a, 18 b are identical and positioned on a common micro image grid 20. For this reason, microimages 18 should be selected that are suitable for use in creating both the first and second visual effects. For example, microimages 18 could be selected that are suitable for use in creating both a visual effect by moiré magnification and a visual effect by integral images. For example, basic geometric shapes such as rectangles, circles, ovals, triangles, etc. can be used. It is also contemplated that symbols may be used, such as currency symbols, although it may be useful to design them with minimal fine details. Typically is one
    27/46
    Effect by integral images a visual effect to change the contrast, since each micro image 18 is identical. If the viewing angle is changed, basically every second microlens 16b looks at the same point on the microimage 18. FIG. 7 shows two exemplary arrays of microimages 18 (first and second microimages 18a, 18b identical).
    The first and second microlenses 16a, 16b are arranged in a manner similar to that described in relation to the embodiment of FIGS. 5a to 5c. The difference in the arrangement between the first microlenses 16a and the second microlenses 16b is the relative gap between the microlenses 16 and / or the orientation of the microlenses 16. The second microlenses 16b have the same gap as the first and second microimages 18a, 18b, which is a prerequisite for an arrangement with integral images / contrast changes. The first microlenses 16a have a different space and / or a different orientation compared to the first and second microimages 18a, 18, which is a prerequisite for a moiré magnification. In any case, the visual effect is present despite the relative positioning of the microlenses 16 and the micro images 18, as long as the alignment is correct or at least almost correct. What changes is the appearance of the visual effect for a particular viewing angle when the relative positioning changes.
    In some implementations, guides are provided to allow consistent relative angular alignment of the microlenses 16 and microimages 18 when the microlenses 16 and microimages 18 are brought together so that the microimages
    28/46 • can be viewed through the microlenses 16. The guides may simply be marks on the document 2 that a user uses to align the microlenses 16 and microimages 18 before considering the optical effect, or a physical feature such as embossed guide rails.
    A further protection against counterfeiting can be provided by applying a protective layer 30 to the microlenses 16, as shown in FIG. Protective layer 30 should have a refractive index that is substantially different from that of microlenses 16, preferably less than that of microlenses 16. As shown, protective layer 30 should also have an outward surface profile that is substantially different from that of microlenses 16 differs. In particular, it is provided that the outward surface profile is flat or essentially flat.
    In particular, the protective layer 30 is particularly useful in obscuring the surface profile of the microlenses 16, which makes reproducing the microlenses 16 substantially more difficult, particularly by making it difficult to position the microlenses 16 and the relative heights of the first and second microlenses 16a, 16b identify.
    Further modifications and improvements can be incorporated without departing from the scope of the present invention. For example, it is contemplated that cylindrical lenses may be used in place of spherical (or aspherical) lenses for the first and second microlenses 16a, 16b. The underlying principle is the same as that already described. That is, either the microlenses 16/46
    or the microimages 18 are positioned on a common grid, the other being arranged such that the first microlenses 16a and first microimages 18a are configured to provide a moiré magnification effect and the second microlenses 16b and second microimages 18b are configured to do so are to provide an effect through integral images. Advantages as described above can be obtained by shaping the first and second microlenses 16a, 16b with at least different heights and possible variations of other parameters. Another variation uses multiple colors (more than two) for microimages 18a and / or 18b.
    It should also be noted that the use of masks in determining the positions of microlenses 16 and / or microimages 18 is simply a useful technique for identifying the required layout of microlenses 16 and / or microimages 18. Other techniques are also contemplated, for example the use of any deterministic algorithms suitably configured to correctly locate microlenses 16 and / or microimages 18.
    / 46
    权利要求:
    Claims (27)
    [1]
    claims:
    1. An optical device, preferably a security device for a security document, comprising a substrate with a first side and a second side, an arrangement of microlenses, which are located on the first side, and an arrangement of microimages, so that the microimages can be viewed through the microlenses are or may be made viewable, the array of microlenses including first and second microlenses, and the array of microimages including first and second microimages, the first microlenses and the first microimages configured to provide a first visual effect, and wherein the second microlenses and the second microimages are configured to provide a second visual effect, the first visual effect being a moire magnification visual effect and the second visual effect being an integral image visual effect, and wherein the first microlenses are related to a on the substrate have a different height than the second microlenses.
    [2]
    2. The optical device according to claim 1, wherein the arrangement of microimages is on the second side opposite the arrangement of microlenses, so that the microlenses and microimages are in a fixed relationship.
    [3]
    3. The optical device of claim 1, wherein the array of microimages is on the first or second side so that the microlenses and microimages must be placed in an overlapping array to view the microimages through the microlenses.
    31/46 * * f ft * «<♦« »* ·« «<« «* · r <rr ♦ * rcrr tft rt
    [4]
    4. The optical device according to claim 1, wherein the first and second microlenses are on raster positions of a conventional microlens raster.
    [5]
    5. The optical device according to claim 1, wherein the first and second micro images are on raster positions of a conventional micro image raster.
    [6]
    6. The optical device of claim 5, wherein the first and second microimages are identical.
    [7]
    7. An optical device, preferably a security device for a security document, including a substrate having a first side and a second side, an array of microlenses located on the first side, and an array of microimages located either on the first side or a second side of the substrate in a non-overlapping relationship or on another substrate of the microimages, the array of microlenses including first and second microlenses, and the array of microimages including first and second microimages, the first microlenses and the first microimages are configured to provide a first visual effect, and wherein the second microlenses and the second microimages are configured to provide a second visual effect, and so that the optical device is configured to have the first visual effect and the second visual effect to be provided when the arrangement of microimages and the arrangement of microlenses are brought into an overlapping configuration.
    32/46 e r e
    fr * ···· * Γ * «« <ι trr «« et 9 rft · cat r ' r rr * 9 ffrr
    [8]
    8. The optical device according to claim 7, wherein the first microlenses have a different height with respect to the substrate than the second microlenses.
    [9]
    9. The optical device of claim 1 or claim 7, wherein one of the first and second microlenses is configured to focus on their associated microimages and the other of the first and second microlenses is configured to defocus on their associated microimages.
    [10]
    10. The optical device according to claim 1, wherein the second visual effect is a visual effect by changing the contrast.
    [11]
    11. The optical device of claim 1 or claim 7, wherein the first and second microlenses include different values for at least one of the following: deflection; Base area, basic shape, F number; and / or focal length.
    [12]
    12. An optical device according to claim 1 or claim 7, wherein both of the first and second microlens rasters and / or both of the first and second microimage rasters are square or rectangular rasters.
    [13]
    13. The optical device of claim 1 or claim 7, wherein the first and second microimages are positioned according to the positions of the corresponding first and second microimage masks.
    [14]
    14. An optical device according to claim 1 or claim 7, wherein the first and second microlenses according to the positions
    33/46 * ν
    Γ · e <* ♦ r vr <«4 I» · · ·· <<«t * f <*« <I f f 'r>«<ei r ( the corresponding first and second microlens masks are positioned.
    [15]
    15. The optical device according to claim 14, wherein each first microlens is only present where the entire first microlens is positioned within a corresponding first microlens mask, and / or wherein every second microlens is only present where the entire second microlens within a corresponding one second microlens mask is positioned.
    [16]
    16. The optical device of claim 1 or claim 7, wherein the microlenses are formed from an embossed and cured curable ink, preferably a radiation curable ink.
    [17]
    17. The optical device of claim 1 or claim 7, wherein the first and second microimages are positioned at substantially the same location.
    [18]
    18. The optical device of claim 3 or claim 7 further including alignment means for guiding a user, such as to achieve correct, or substantially correct, relative angular alignment between the array of microlenses and the array of microimages.
    [19]
    19. Document, preferably a security document and even more preferably a banknote, which has an optical device according to claim 1 or claim 7.
    [20]
    20. The document of claim 19, wherein the document comprises a substantially transparent document substrate, of which
    34/46 ff ♦ »rv ·« v * · <· * · <«« 4 «* ♦ * * · tff rf cr ♦ <<'r. "."" R , a section corresponds to the substrate of the optical device.
    [21]
    The document of claim 19, wherein the document comprises a substantially opaque document substrate, wherein the optical device is either attached to a surface of the document substrate or positioned within a cut region of the document substrate.
    [22]
    22. A method of manufacturing the optical device according to claim 1 or claim 7, comprising the following steps:
    Applying radiation curable ink to a first side of a transparent substrate;
    Embossing and curing the radiation-curable ink, thereby shaping the arrangement of microlenses; and
    Print the array of microimages on either the first page or the second page.
    [23]
    23. The method of claim 22, wherein the arrangement of microlenses coincides with the arrangement of microimages that is positioned on the second side of the substrate opposite the microlenses.
    [24]
    24. The method of claim 22, wherein the step of embossing the array of microlenses and the step of printing the microimages are performed simultaneously or substantially simultaneously.
    [25]
    25. The method of claim 22, wherein the substrate corresponds to a region of a larger document substrate.
    35/46 «« * t «>
    rr · * ♦ · et rr
    [26]
    26. The method of claim 22, wherein the first and second micro images are printed in the same document.
    [27]
    27. The optical device according to claim 7, wherein the first visual effect is a visual effect by moiré magnification and the second visual effect is a visual effect by integral images and preferably a visual effect by contrast changes.
    类似技术:
    公开号 | 公开日 | 专利标题
    DE112016001903T5|2018-01-04|Optical device with combined microlenses
    EP1979768B1|2018-09-26|Multilayer body with microlens arrangement
    DE112011100983T5|2013-04-11|Security document with integrated security device and manufacturing process
    DE112017001245T5|2018-11-29|Micro-optical device with structure with integrated focusing element and picture element
    CH705753B1|2016-03-15|Optically variable facility.
    DE112016000989T5|2017-11-23|An aperiodic moiré security element and method for its manufacture
    DE112011102365T5|2013-04-25|Optically variable device
    DE112015001892T5|2017-02-02|Hybrid security device for security document or security token
    EP2867031B1|2016-08-10|Safety element having microstructures having diffractive structures, and a method for manufacture and verification
    DE112014000889T5|2015-10-29|Safety device with hidden images
    DE102008062475A1|2010-06-17|Security element and security paper
    DE112010003249T5|2013-05-02|Optically variable devices and methods of manufacture
    DE102009007779B3|2010-10-07|A method for producing a visually perceptible without technical aids security feature, security feature for plastic-based value or security document and document with at least one such security feature
    DE102014004700A1|2015-10-01|Security element with a lenticular image
    DE112014001682T5|2015-12-24|Lens foil based safety device
    DE112012004012T5|2014-07-17|safety device
    DE112016003353T5|2018-04-05|Optical device with an optical array
    DE112016000676T5|2017-11-09|Angular effects producing diffractive device
    DE112015001463T5|2016-12-15|Volume holograms for security documents
    DE112017001373T5|2018-11-29|Micro-optical device with double-sided optical effect
    AT519179A2|2018-04-15|Optical device with combined microlenses
    DE112018001975T5|2020-02-20|Optical security device and manufacturing method
    DE112018003109T5|2020-03-26|Micro-optical device for projecting multi-channel projected image representations
    DE112018003095T5|2020-03-26|Security document containing an optical security feature
    AT519066A2|2018-03-15|Diffractive device with embedded light source mechanism
    同族专利:
    公开号 | 公开日
    AU2015100670A4|2015-06-18|
    AT519179A5|2020-04-15|
    AU2015100670B4|2015-10-08|
    引用文献:
    公开号 | 申请日 | 公开日 | 申请人 | 专利标题
    DK1695121T3|2003-11-21|2014-06-30|Visual Physics Llc|Microoptic security and image presentation system|
    DE102004044459B4|2004-09-15|2009-07-09|Ovd Kinegram Ag|Security document with transparent windows|
    MX2009002818A|2006-09-15|2009-05-15|Securency Int Pty Ltd|Radiation curable embossed ink security devices for security documents.|
    CN104834029B|2015-04-16|2016-09-28|上海天臣包装材料有限公司|Micro-optical device of double-face imaging and its preparation method and application|MA42899A|2015-07-10|2018-05-16|De La Rue Int Ltd|PROCESSES FOR MANUFACTURING SAFETY DOCUMENTS AND SAFETY DEVICES|
    法律状态:
    2021-04-15| REJ| Rejection|Effective date: 20210415 |
    优先权:
    申请号 | 申请日 | 专利标题
    AU2015100670A|AU2015100670B4|2015-05-21|2015-05-21|Combination microlens optical device|
    PCT/AU2016/050383|WO2016183635A1|2015-05-21|2016-05-20|Combination microlens optical device|
    [返回顶部]