EP3397500A1

EP3397500A1 - Secure item comprising a revealing screen and a combined image

Info

Publication number: EP3397500A1
Application number: EP16820293.5A
Authority: EP
Inventors: Philippe Dietemann; Fernand GARCIA DE CRUZ
Original assignee: Oberthur Fiduciaire SAS
Current assignee: Oberthur Fiduciaire SAS
Priority date: 2015-12-29
Filing date: 2016-12-23
Publication date: 2018-11-07
Anticipated expiration: 2036-12-23
Also published as: FR3046111A1; PL3397500T3; WO2017114803A1; FR3046111B1; KR20180098649A; RU2018123771A3; CN109070619A; US20190039402A1; BR112018013389A2; US10710394B2; EP3397500B1; CN109070619B; RU2018123771A; RU2731962C2

Abstract

The invention relates to a secure item comprising a revealing screen (4) and a combined image (I), or an assembly comprising a secure item (10) and another object (100), the secure item (10) comprising one of the revealing screen (4) and the combined image (I), and the object (100) comprising or forming the other one of the revealing screen (4) and the combined image (I), the combined image being made up of a plurality of interlaced images (I₁ to I_n) each interlaced image (I₁ to I_n) and/or the revealing screen being made up of a plurality of elements (i_i to i_n, p_i to p_n, 5a, 5b), the revealing screen (4) making it possible, when placed on top of the combined image (I), to observe various revealed images (I_r) by moving the revealing screen (4) relative to the combined image (I) and/or by changing the observation angle, the revealed images each comprising a certain proportion (P₁_; P_n) of each interlaced image I₁ to I_n), and the elements (i_i to i_n, p_i to p_n, 5a, 5b) being made up of one or more micro-patterns (7).

Description

SECURE ARTICLE WITH A FRAME OF REVELATION

AND A COMBINED IMAGE

The present invention relates to the field of secure articles.

Background

In order to guard against counterfeits or falsifications and to increase the level of security, it is known to use security elements applied on the surface or introduced in bulk or in windows (s) in a secure article, for example a label, packaging, especially for drugs, food, cosmetics, electronic parts or spare parts.

The secure article may in particular be chosen from among a means of payment, such as a bank note, a bank card, a check or a restaurant ticket, an identity document such as an identity card, a visa, a passport or driver's license, a secured card, a lottery ticket, a ticket or a ticket to events.

Patent applications EP 2 367 695, EP 2 585 308 and EP 2 586 014 and patent EP 2 454 102 disclose the effects of masking imbricated images by a revelation screen which, when the revelation screen and the image are superimposed, the observation of an image by displacement of the revelation frame with respect to the image or by change of the angle of observation.

However, these patents have nested images in the form of solid lines.

It is also known from the patent application EP 2 740 607 a system comprising a revelation screen, a layer having pigments orientable by an external magnetic field and a magnetic layer having a north and south poles frame, the revelation frame and the weft of north and south poles being of different colors. WO 2014 096 794 discloses a first frame on which a second surface frame is embossed, the weft lines of the first frame having the same color in visible light and different colors when they are observed under a combination of visible and invisible lights and the two frames being such that the device has a different color, depending on the viewing angle, when exposed to a combination of visible and invisible lights. summary

There is a need to benefit from secure articles comprising an anti-counterfeiting optical system using the tools of the actors of the field of secure articles, capable of producing optical effects that can contribute to the authentication and / or identification of the article , and whose possible incorporation into an article such as a paper can be done relatively easily.

The invention aims to meet this need and has for its object, according to a first aspect, a secure article comprising a revelation frame and a combined image, or an assembly comprising a secure article and another object, the secure article having one of the revelation screen and the combined image and the object comprising or forming the other of the revelation screen and the combined image,

the combined image being composed of a plurality of nested images, each nested image and / or the revelation frame being composed of a plurality of elements,

the revelation frame, when superimposed on the combined image, to observe different revealed images by displacement, when the revelation frame and the combined image are superimposed, for at least one given position and orientation of the revelation frame with respect to the combined image, and / or by changing the angle of observation, the revealed images each comprising a certain proportion of each nested image, and

at least one element being composed of one or more micromotives.

The fact that the elements are composed of micromotives makes it possible to reinforce the security of the article. In fact, the presence of the micromotives imposes a resolution of the combined image and / or the high revelation frame and, as a result, makes the counterfeiting of the secured article more difficult.

Thanks to the invention, it is possible to benefit from a secure article offering a new means of authentication, consisting of the formation of different revealed images, leading for example to the formation of a particular colored pattern easily recognizable by the man in the street.

The other aforementioned object is for example similar in its function and / or in its form to the secure article according to the invention. For example, the secure article and the other object are bank notes, especially with the same fiduciary value. The article secure and the other object can then be differentiated from each other only by a serial number for example.

By "the revealed images each having a certain proportion of each nested image", it is understood that the revelation frame reveals a certain proportion of each of the nested images of the combined image to form the revealed image. For each image revealed, the proportion of a nested image is between 0 and 1, the value 0 being assigned to a nested image when the latter is not a component of the revealed image, that is to say when the latter is completely obscured by the revelation frame and the value 1 being assigned when the entirety of the nested image is a component of the revealed image, that is to say when the latter is not the same. all obscured by the weave of revelation.

micropatterned

All elements of all the nested images and / or the revelation frame may be composed of one or more micromotives. This makes it possible to reinforce the security of the secured article, the micromotif being for example observed using a magnifying glass and constituting a level 2 security.

The micromotives can each be a number, a text, one or more alphanumeric signs, one or more ideograms, an object, a person, an animal, a monument, preferably a number, a text, an alphanumeric sign or a several ideograms.

The one or more nested image elements and / or the revelation screen may each be composed of several micromotives, in particular a micropod repeating periodically in one or more directions over the entire dimension of the element according to this or these directions. .

The micromotives of an element can form a continuous appearing line, especially when observed with the naked eye at a normal viewing distance.

By "normal observation distance" is meant the usual observation distance of a secure article, for example 30 cm and preferably 15 cm.

Advantageously, all the elements of the same nested image are composed of the same micromotif, in particular of a micropod repeating periodically in one or more directions over the entire dimension of the elements according to this or these directions. The micromotives have at least one dimension less than or equal to 1 mm, better less than or equal to 100 μιη, more preferably less than or equal to 50 μιη. In view of their dimensions, the micromotives are not apprehensible to the naked eye and the nested image elements and / or frame appear homogeneous. For example, the color of the nested picture elements and / or the revelation frame depends on the color of the micropatterns composing them. Red-colored micromotives form red-colored elements that appear uniform.

Preferably, the micromotives are of different colors, so that the elements belonging to different interleaved images are of different colors, each of the elements having for example the color of the microparticles composing it. For example, there is a color difference ΔΕ * 94 according to the CLE. 1994 greater than or equal to 2, preferably greater than or equal to 3.

As is commonly accepted and specified in the CLE. In 1994, color is defined by the combination of three parameters of hue, saturation and brightness. The hue is the perception of the color measured on a color wheel, the saturation is the purity of the color, and the brightness is the degree of lightening or darkening of a color.

Preferably, the micromotives are of different hues, so that the elements belonging to different nested images are of different hues, each of the elements having for example the hue of the microparticles composing it.

The micromotives belonging to different nested images may be different in their aspects, in particular their shapes, and / or their hues, opacities, saturations, luminescence or gloss, and / or may present a contrast, in particular a contrast of saturation, of intensity, hue and / or luminance, and / or a color difference sufficient to distinguish, especially under white light, two adjacent imbedded image elements when observed with a certain magnification, for example with a magnifying glass. For example, there is a color difference ΔΕ * 94 according to the CLE. 1994 greater than or equal to 2, preferably greater than or equal to 3.

The colors of the micromotives can be primary colors or not.

The micromotives can be fluorescent and have different aspects, including different colors, under UV light.

Micromotives can be luminescent. The micromotives can be represented as positive or negative.

Each nested image element and / or revelation frame may comprise a bottom on which the micromotor or micromotives are made.

For example, the nested and / or raster image elements are lines, and the nested and / or raster image lines each consist of a micropat repeating itself periodically over their entire length.

Preferably, the micromotives are substantially of the same width / as the line of nested images and / or weft they compose, in particular a width / less than or equal to 1 mm, better than or equal to 100 μιη, and even better less than or equal to 50 μιη.

Combined image

Preferably, the combined image comprises a periodic alternation of nested image elements in one or more directions.

The combined image may comprise at least two nested images, preferably at least three.

The combined image may include at least two elements of each nested image, preferably at least three.

According to the or each of the directions, the successive elements of the same nested image may be spaced apart by a distance defining a period.

The or each period may be between 10 μιη and 1 mm, preferably between 50 μιη and 200 μιη.

The elements belonging to different nested images, in particular to at least two different nested images, may be different in their aspects, in particular their hues, opacities, saturations, luminescences or glosses, and / or may have a contrast, notably a saturation contrast. , intensity, hue and / or luminance, and / or a color difference sufficient to distinguish, especially under white light, two adjacent imbedded image elements when observed with a certain magnification for example at using a magnifying glass. Thus, at least two of the, better all nested images, are of different aspects.

Preferably, the nested picture elements belonging to different nested pictures are of different colors. For example, there is a gap colorimetric ΔΕ * 94 according to the CLE. 1994 greater than or equal to 2, preferably greater than or equal to 3. This allows to have a combined polychrome image.

Preferably, the nested picture elements belonging to different nested pictures are of different hues.

The nested picture elements of the same nested picture preferably appear in the same color but in a different color from those of the other nested pictures. During the superposition of the revelation frame with the combined image, at given observation conditions, the image revealed by the revelation frame can then be an image whose color is defined by the proportion of each visible nested image. , that is, the proportion of each color. The images revealed by the revelation frame are of different colors. For example, the combined image has three nested images of primary colors, including respective colors red, green and blue, and the revealed images are each of a color depending on their proportion in each of the nested images, the color being easily determinable. by its RGB coordinates. The RGB coordinates are in the form of three numbers between 0 and 255 characterizing said color, each number representing the proportion of one of the red, green and blue components for obtaining said color.

By "given viewing conditions" is meant a given position and orientation of the revelation frame with respect to the combined image and a given viewing angle of the revelation frame and the combined image.

Preferably, the combined image, and the nested images that it comprises, are raster images; the combined image can be a colored raster.

The nested picture elements may be luminescent, in particular fluorescent, and have different aspects, including different colors under UV light. This makes it possible to have revealed images that can be observed under UV light, different or different from the revealed visible images in visible light.

When the nested picture elements are luminescent, they may or may not be visible in white light.

The nested image elements are preferably all of the same size depending on the or each of the directions. The size of the nested picture elements according to the one or more directions is preferably equal to the period in that direction divided by the number of nested pictures. This dimension may be less than or equal to 1 mm, better less than or equal to 100 μιη, more preferably less than or equal to 50 μιη. Thus, the nested picture elements are joined. Each nested picture element may be partially superimposed with one of the adjacent elements, the superimposition width being less than or equal to 10%, more preferably 5% of the dimension of the nested picture element in said direction.

In a variant, at least two nested image elements may be of different dimensions depending on the one or more directions.

The nested picture elements preferably have the same general shape. For example, the combined image comprises a periodic alternation of lines of interleaved images, longitudinal axes parallel to each other in one direction. The longitudinal axes of the nested image lines define a general orientation of the combined image.

Each nested image may be formed of continuous or discontinuous lines, preferably continuous lines, two successive lines of the same nested image being spaced apart by a distance S defined between the longitudinal axes of the two adjacent lines, the latter defining the period of time. combined image. The lines of the same nested image can be all identical or not.

The lines of a nested image are preferably all of the same length. But it may be otherwise, and at least two lines of nested images may be of different lengths.

Each line of a nested image is preferably of width / constant over its entire length, its longitudinal edges being parallel to each other.

The nested image lines are preferably all of the same width. The width / lines of nested images is preferably equal to the period divided by the number of nested images. Thus, the nested image lines are joined. The width / lines of nested images may be less than or equal to 1 mm, better still less than or equal to 100 μιη, more preferably less than or equal to 50 μιη. Each line of nested images may be partially superimposed with one of the adjacent lines, the width of the superposition being less than or equal to 10%, better 5% of the width of said nested image line.

In a variant, at least two lines belonging to different nested images are of different widths.

The nested image lines preferably have the same general shape, in other words, the edges of the nested image lines are parallel to each other. The nested image lines may be rectilinear or not, for example curved, wavy or crenellated.

In a variant, the nested images may each be composed of elements, in particular lines, continuous or discontinuous, forming a macromotif and each revealed image may correspond to a nested image so that a displacement of the revelation frame relative to the combined image and / or that a change of the angle of observation makes it possible to go from one nested image to another and thus from one macromotif to the other. For example, the combined image corresponds to the decomposition of a movement including a text, alphanumeric signs, ideograms, an object, a person and / or an animal, each pattern corresponding to a stage of the movement.

The combined image may have a resolution greater than or equal to 800 dpi, better, greater than or equal to 1000 dpi. In other words, it requires for its realization printing means or other manufacturing capable of producing details corresponding to such a resolution. With such a resolution, the micromotives are not visible to the naked eye at a normal viewing distance and the nested image elements appear as homogeneous elements. This enhances the anti-copy and anti-counterfeit security of the article.

The combined image can be as such, that is to say by being observed directly without passing through the revelation screen, of substantially homogeneous appearance to the naked eye at a normal viewing distance in view of his finesse. For example, the combined image may appear to the naked eye at a normal viewing distance as having a uniform appearance in areas of its macrometric size surface, including a uniform color throughout its surface. This allows, if desired, to have revealed images that look homogeneous to the naked eye at a normal viewing distance.

In the case of nested images of different colors, the combined image and the revelation frame can be arranged in such a way that the revealed images each appear in a solid color.

The combined image may have any suitable contour, and in particular its outline may define a pattern that is otherwise on the article; the combined image is for example a contour defining a pattern such as a character, animal, plant, monument or alphanumeric sign, which appears elsewhere on the article, for example in the form of an impression or a watermark .

Revelation frame

Preferably, the revelation frame comprises a periodic alternation of two weft elements in one or more directions otherwise called orientations.

Preferably, the revealing frame comprises at least four weft elements, more preferably at least six.

In a variant, the revelation frame comprises periodic alternation of at least three weft elements. In particular, a revelation frame comprising a periodic alternation of an infinity of frame elements forms a periodic gradient.

The frame elements are preferably opacities, transparencies and / or different hues, in particular a weft element is blackout, in particular appears opaque and the other element is non-obscuring, for example appears non-opaque. For example, the revelation frame is formed of a periodic alternation of occulting elements, for example black opaque substantially and non-occulting elements, for example transparent, otherwise called interlines. As a result, when the revelation frame and the combined image are superimposed, the blackout elements prevent the observation of part of the combined image and the non-occulting elements reveal the rest of the combined image.

Alternatively, the shadow frame member is a filter which is such that when superimposed on the combined image, the combined image portions on which it is superimposed are not visible. For example, the revelation frame is a color filter that does not let any of the colors of the combined image pass. Preferably, the raster elements have the same shape as the nested image elements. That is, if the nested picture elements are in the form of lines, the raster elements are in the form of lines.

The blackout frame elements can be composed of micromotives.

Advantageously, when the revelation frame and the combined image are superimposed, the frame and the combined image have the same or the same orientations. In particular, the directions in which the frame elements alternate periodically and the directions in which the nested picture elements alternate periodically are identical. As a result, when the revelation frame and the combined image are superimposed, the frame elements are superimposed on the nested image elements of the combined image; the blackout elements prevent the observation of a portion of the nested image elements of the combined image, and the other nested image elements form the revealed images.

For the same dimension in one direction of the nested picture elements, a revealing frame having small-size blackout elements allows the observation of a revealed image having a greater proportion of nested images, especially colors, that a revealed image observed with a revelation frame having elements of occulting frames of larger size.

The revealing frame has blackout frame elements and non-blackout frame elements.

The blackout elements provide a visual contrast with the non-blackout elements. The boundary between an occulting element and a non-occulting element is thus determined by the fact of being able to observe the desired effect or not, by superposition with the combined image.

This observation can be done through the non-occulting elements. Alternatively, the combined image is located between the revelation frame and the observer, and the blackout elements prevent the observer from discerning the blackout elements of the nested image that are superimposed on it. In examples, the non-occulting element is perfectly transparent or of a sufficiently low uniform opacity or of a hue sufficiently clear to allow to observe through it or on him the element or elements of nested images leading to the desired effect. In this case, the dimension according to a direction of the non-occulting element corresponds to the width in this direction of the perfectly transparent zone or of sufficiently low uniform opacity or shade sufficiently clear. In these examples, the transition between a blackout element and a non-blackout element is straightforward. In other examples, the blackout element and / or the non-blackout element form (s) a gradient. In this case the limit of the non-occulting element in one direction, useful for determining its dimension in this direction, is that from which the opacity is sufficiently strong or the hue sufficiently dark to prevent the desired effect from being seen. through or on the element. For example, in the case where the transition between an occulting element and a non-occulting element is done with a continuous gradient of opacity gray varying in a direction between Opmin and Op _max , and that beyond an opacity Op _occ it is no longer possible to see the desired effect through the element, the dimension of the non-occulting element is given by the dimension in this direction of the zone of the element where the opacity is lower or equal to Op _OC c.

Preferably, the revelation frame has a finite number of raster elements. More preferably, the raster elements have no gradient.

More preferably, the non-occulting elements are each of opacity or brightness (L * in the system (L *, a *, b *) CIE94) uniform, which can be zero, respectively weak, and the blackout elements are also preferably of opacity or uniform brightness.

Preferably, the period in one direction is substantially equal to the period of the combined image along one of its directions.

The revelation frame may comprise at least 5 blackout frame elements according to the or each of its directions.

For example, the revelation frame comprises a periodic alternation of two raster lines of longitudinal axes parallel to each other.

Preferably, the two weft lines have parallel longitudinal axes and define a general orientation of the revelation frame.

Preferably, each raster line is of constant width over its entire length, its longitudinal edges being parallel to each other. The blackout weft lines and the non-blackout weft lines that alternate with each other may be of the same width or not. Preferably, the raster lines have the same general shape as the nested image lines.

The two weft lines are preferably rectilinear, but alternatively the revelation weft comprises weft lines that are not straight, being for example curved, wavy or crenellated.

Preferably, the edges of one of the weft lines are parallel to the edges of the other of the weft lines.

The resolution of the revelation frame is preferably greater than or equal to 800 dpi, more preferably greater than 1000 dpi.

The revelation weft can be as such of homogeneous appearance to the naked eye at a normal viewing distance, given its fineness. In particular, the revelation screen may appear to the naked eye at a normal viewing distance and in white light as having an appearance, including a uniform color.

The revealing frame may have any shape contour, for example circular, oval, disk-shaped, star-shaped, polygonal, for example rectangular, square, triangular, hexagonal, pentagonal or diamond-shaped, or form a more complex pattern, in particular a pattern representing a text, an alphanumeric sign, an ideogram, an object, a person, a plant, a monument and / or an animal.

The revelation frame may include an inclusion of another security means, in particular another revelation frame.

The revealed images are observable in reflected light and / or transmitted light, and preferably they are observable in both reflected light and transmitted light.

Advantageously, the revealed images have a homogeneous appearance with the naked eye at a normal viewing distance, including a homogeneous color.

The revealed images are preferably observable both on the side of the revelation frame and on the side of the combined image.

Preferably, the revealed images have different aspects, in particular different colors and / or glosses.

The revealed image may consist of at least two, preferably at least three, adjacent nested images.

Alternatively, the revealed image may include a single nested image. Preferably, the revealed image forms a macromotif when the revelation frame is superimposed on the combined image at given viewing conditions. Preferably, this macromotif is visible when the orientation of the revelation frame is the same as that of the combined image.

Preferably, the revealed images form macromotifs having different aspects, in particular different colors and / or glosses, for example having different RGB coordinates and / or different patterns, these patterns corresponding for example to the different steps of a movement.

The macromotif may change its appearance when moving in the one or more directions of the combined image, and / or a change in viewing angle. For example, in the case of a combined image formed of nested images of different colors, the pattern may change color. In the case of nested images corresponding to the decomposition of a movement, the macromotif can change so as to restore an impression of movement.

The macromotif can disappear when the orientation of the revelation frame is changed relative to that of the combined image, especially when the orientation of the revelation frame becomes different from that of the combined image.

The macromotif formed may be of any form, including a text, an alphanumeric sign, an ideogram, a geometric shape, an object, a person and / or an animal.

The secure article or the assembly may comprise a second revelation frame separated from the first revelation frame and intended to be superimposed on the same combined image.

Alternatively, the combined image may be formed of a periodic alternation of image pixels interleaved in two non-parallel directions.

By "pixels", we understand an elementary pattern. A pixel can be of polygonal shape, in particular triangle, hexagon, rectangle or square.

The revelation frame may be formed of a periodic alternation of occulting frame pixels in the same two directions and with the same periods in both directions. Thus, the blackout frame pixels prevent the observation of a portion of the nested image pixels leaving only a certain proportion of each nested image for each image revealed. As a variant, when the combined image is formed of a periodic alternation of image pixels interleaved in two non-parallel directions, the associated revelation frame can be simplified by defining a periodic alternation of blackout frame elements and elements. non-occulting frame in the form of lines.

Observation

The combined image and / or the revealing frame can be worn on the secured article or the other object by a printing process, in particular offset, intaglio, laser, gravure, typography or serigraphy, the combined image and / or the revelation screen being printed with colored or non-colored inks, visible to the naked eye, under ultraviolet (UV) and / or infrared (IR), opaque, fluorescent, translucent and / or transparent.

The combined image may be printed in particular by a combination of colors having sufficient respective colorimetric differences, for example printing in CMLN (Cyan, Magenta, Yellow, Black) and preferably in RGB (Red, Green, Blue).

Advantageously, metallizations and / or demetallizations are used in order to avoid counterfeiting by printing.

Thus, the combined image and / or the revelation screen may comprise metallizations and / or demetallizations, for example of different metals, in particular copper or aluminum and their alloys.

The combined image and / or the revelation screen may be further printed with liquid crystals and carried on an area of the light-polarizing secure article such that the combined image and / or the revelation screen visible only when folding the article on itself or through an external polarizer.

At least one of the combined image and the revelation screen may appear on an area of the at least partially transparent secured article, the superposition of the revelation screen and the combined image being made by folding secure item or overlay the secure item with the other item. The revelation frame may allow, when superimposed at least partially on the combined image of the secure article or the other object, to observe different revealed images by a relative displacement of the revelation frame with respect to the combined image according to the one or more directions of the combined image and the revelation screen. The folding of the secure article can be done along a median line of the article, preferably parallel to one side of the article, for example along a center line passing through the middle of the length of the article.

The revelation screen and the combined image can be superimposed by being separated from each other by a constant thickness interval. This gap may be formed by a transparent or translucent substrate having on the side of a first face of the substrate the combined image and on the side of a second face of the substrate, opposite to the first, the revealing frame superimposed on the image combined. The revelation frame can then make it possible to observe different revealed images, by a parallax effect, during a change in the observation direction of the secure article. The interval between the revealing frame and the combined image is preferably greater than or equal to the period of the revealing frame, in particular between 10 μιη and 1 mm, being for example less than 25 μιη.

In this case, the revelation frame may make it possible to observe different revealed images during a change in the observation direction of the secured article.

The substrate may comprise or consist of a thermoplastic material, for example a polyolefin, for example polyethylene (PE), polyvinyl chloride (PVC), polyester, polyethylene terephthalate (PET), polycarbonate (PC), polyester carbonate (PEC), polyethylene terephthalate glycol (PETG), acrylonitrile butadiene styrene (ABS) or a light-collecting film, for example of the "waveguide" type, for example a commercially available polycarbonate-based luminescent film by the company BAYER under the name LYSA ^® .

The substrate may comprise cellulosic fibers and in particular paper. In particular, the substrate may be a sufficiently translucent paper to reveal the nested images, including a tracing paper.

The substrate may also be locally or locally transparent, by the embodiment as described in patent EP 1252389 or by application of a generally fatty composition which permanently renders it transparent, for example a composition made of oil and transparent mineral material, as described in US Patent 2,021,141, or for example a composition in the form of a wax combined with a solvent. The substrate can also be made transparent by locally applying a wax by heat transfer as described in US Pat. No. 5,118,526.

It is also possible to use for the substrate a fibrous layer comprising a hot-melt material, for example polyethylene, as described in patent EP 0 203 499, which under the local action of heat will vary in its transparency.

Secure article

The secure article may be at least partially made of paper or plastic, including a laminated plastic sheet or extruded.

The secure article may comprise at least one paper jet, in particular based on natural and / or synthetic fibers, for example cotton or linen fibers in the case of a banknote.

The secured article may be at least partially transparent, opaque or translucent, in particular opaque in reflected light and translucent in transmitted light.

The combined image and / or the revelation frame may be carried by a film, a lamination strip, a patch and / or a foil on the secured article. The film, the lamination strip, the patch and / or the foil may comprise metallizations and / or demetallizations, for example aluminum or copper, or all types of prints.

By "patch" is understood an element of dimensions smaller than that of the secure article and which may not extend to the edge of the article. The patch may have a polygonal, circular, oval or more complex pattern, including a pattern representing a text, an alphanumeric sign, an ideogram, an object, a person, a plant, a monument and / or an animal.

By "foil" or "lamination strip", it includes an element applied in particular hot, for example by transfer to the secure article including a carrier structure.

The film, the lamination strip, the patch and / or the foil may comprise holographic impressions and / or liquid crystals.

The combined image and / or the revelation frame may be further carried by a security thread, embedded in the surface, in bulk or preferably in window (s) in the secured article.

The combined image and / or the revelation frame may be incorporated into a window in the secure article. The window can be formed on the secure article during its manufacture.

The window may be formed by a lack of material, for example the local absence of paper, above or below the combined image and / or the revelation screen, the window preferably being at least partially transparent or translucent on the side of the combined image and / or the revelation frame opposed to the lack of material.

The window may still not have a lack of material. The window may for example be at least partially transparent or translucent above or below the combined image and / or the revealing frame, the transparent or translucent areas being superimposed on one another so as to be able to observe both opposite sides of the secure article.

The window can still be through. The window may have material gaps superimposed on both sides of the revelation frame and / or the combined image. Two sides of the combined image and / or the revelation frame can thus be observed directly and not through transparent or translucent areas. The revelation frame and / or the combined image may be incorporated wholly into the window or partially.

The article may still have a plurality of windows as described above. The windows may or may not all be of the same type. Examples of embodiments of windows in secure articles are for example given in GB 1 552 853 which discloses the creation of a window including transparentization, laser cutting, abrasion or mechanical incision, EP 0 229 645 which describes the creation to the using masks of a window on one side or on both sides of a bijet paper, WO 2004/096482 which describes the creation of a laser cutting window, CA 2 471 379 which describes the creation of a transparent window and association with a security element and WO 2008/006983 which describes the creation of a transparent window on a bijet paper.

The secure article may further comprise a security thread having the combined image and / or the revelation frame, in particular a succession of combined images and / or revelation frames.

The secure article may also include two security son, one carrying at least one combined image and the other bearing at least one corresponding revelation frame. The safety wire or wires may have a width sufficient to allow to include the combined image and / or the revelation frame in full. The width of the security son or son is preferably between 3 and 20 mm, more preferably between 4 and 10 mm and for example equal to 6 mm.

As indicated above, the revelation frame and / or the combined image advantageously appear on an area of the at least partially transparent article, in particular the revelation frame and / or the combined image may be at least partially transparent.

The at least partially transparent zone may correspond to a recess, crossing or not, of the article in which the revealing frame and / or the combined image are placed.

The zone is for example constituted by a translucent tracing paper.

The zone may also be constituted by a polymer layer comprising for example polyethylene (PE), polyvinyl chloride (PVC), polyethylene terephthalate (PET), polycarbonate (PC), polyester carbonate (PEC), polyethylene terephthalate glycol (PETG), of acrylonitrile butadiene styrene (ABS) or a light-collecting film, for example of the type "wave guide", for example a polycarbonate-based luminescent film sold by BAYER under the name ^® LYSA .

The secure article, and the elements it comprises such as a security thread, a patch and / or a foil, may include one or more additional security elements as defined below.

Among these additional security features, some are detectable to the eye, daylight or artificial light, without the use of a particular device. These security elements comprise for example colored fibers or boards, fully or partially printed or metallized wires. These security elements are called first level.

Other types of security elements are detectable only with a relatively simple device, such as a lamp emitting in the ultraviolet (UV) or infrared (IR). These security elements comprise, for example, fibers, boards, strips, wires or particles. These security elements may be visible to the naked eye or not, being for example luminescent under a lighting of a Wood lamp emitting at a wavelength of 365 nm. These security elements are said to be second level. Other types of security elements still require for their detection a more sophisticated detection device. These security elements are for example capable of generating a specific signal when they are subjected, simultaneously or not, to one or more external excitation sources. The automatic detection of the signal makes it possible to authenticate, if necessary, the article. These security elements comprise, for example, tracers in the form of active materials, particles or fibers capable of generating a specific signal when these tracers are subjected to optronic, electrical, magnetic or electromagnetic excitation. These security elements are said to be third level.

The additional security elements present within the secured article may have first, second, or third level security features.

The secure article may be a means of payment, such as a bank note, a check, a bank card or a restaurant ticket, an identity document such as an identity card or a visa or a passport or a driving license, a lottery ticket, a secured card, a ticket or a ticket for cultural or sports events.

imager

In a variant, the other object is an electronic imager making it possible to form a first image, the first image being the revealing frame or the combined image, so that it can be superimposed on a second image present on the secured article, the second image being the other of the revelation frame and the combined picture.

The term "electronic imager", an electronic device for producing an image by display or projection.

The electronic imager may include a screen on which the first image is displayed.

The electronic imager may comprise a screen of any known type, for example a computer screen, television, mobile phone, a book or electronic diary, a personal digital assistant ("Personal Digital Assistant"), digital tablet, a watch dial, this list being non-limiting. The electronic imager may be a projector, with or without a screen on which the projection is made. The projector can project the first image on a background or on the security article.

The electronic imager may be a projector of any known type, for example a slide projector, a video projector, an overhead projector, a pico projector or nanoprojector, for example a miniaturized projector integrated in a portable device (PDA, mobile phone, laptop, for example), a cinematographic projector, this list being non-limiting.

The electronic imager preferably makes it possible to generate a pixelated image, each pixel of which is addressable individually, preferably with at least 256 gray levels or colors, and / or with a resolution of between 50 and 1000 dpi ("Dot Per Inch" or "Points Per Inch").

The electronic imager may be a projector projecting visible, infrared (IR) and / or ultraviolet (UV) light.

The electronic imager may include a LCD screen ("Liquid

Crystal Display "), LED" Light Emitting Diode "), OLED (" Organic Light Emitting Diode "), laser, plasma, electrochrome, FED (" Field Emission Display "), SED (" Surface-conduction Electron-emitter Display ") , LCOS ("Liquid Crystal On Silicon") or a cathode ray tube.

The electronic imager preferably comprises a liquid crystal display

(LCD).

The screen may have a resolution of between 50 and 600 dpi, better between 100 and 300 dpi, for example equal to 160 dpi.

The second image may appear on an area of reduced opacity of the secure article. Such a zone of reduced opacity may especially correspond to a zone of lesser thickness, to a zone made transparent or to a zone comprising at least one layer of a material of less opacity. In particular, the opacity of said zone of reduced opacity will be sufficiently small to allow a transmission observation of the first image. Preferably, the second image is visible in transmission and in reflection.

The second image may appear on an at least partially transparent or translucent area of the secured article. When the electronic imager produces the first image by means of a polarized light, the second image preferably appears on an at least partially transparent or translucent zone, in particular an at least partially transparent window.

The first image produced by the electronic imager can be displayed on the electronic imager, for example on a screen of the electronic imager.

Alternatively, the first image is projected by the electronic imager, for example on a background or on the secure article. In particular, when the first image is projected on a background, the second image of the secure article can be superimposed on the first image projected on the background. In a variant, the first image is projected at least partially on the second image of the secured article.

The article and the imager can come into contact or not when the images are superimposed.

The first image and / or the second image may have polarization properties.

For example, the first image is produced by the electronic imager by means of a polarized light, in particular a polarized light rectilinearly, circularly or elliptically. The electronic imager may include a screen emitting polarized light or projecting polarized light.

The secure article may include a polarizing filter. In particular, the second image can be made using a polarizing filter.

The second image can be made according to at least one of the following steps:

producing one or more perforations in at least one polarizing filter to form the second image,

local heating of at least one polarizing filter, for example using a laser, so as to locally remove the polarizing properties of the filter and to form the second image,

selective application, for example by printing and / or gluing, on at least one polarizing filter, of a diffusing material, for example a colloidal silica and / or an adhesive strip, to form the second image, performing at least one selective etching by chemical reaction and / or by emitting light radiation, in particular ultraviolet (UV) and / or infrared (IR) and / or laser radiation, onto at least one polarizing filter, optionally at the using a mask, to form the second image, in particular so as to locally cancel the polarizing effect of the filter,

application, in particular by printing or coating, of at least one polarizing effect, in particular of a polarizing compound, for example using an ink comprising said polarizing compound, on a given non-polarizing substrate, in particular a polymer film , to form the second image,

- application, in particular by printing or coating, of at least one composition comprising liquid crystals, cholesteric including, for example such as that sold by the company SICPA under the name Oasis ^®, on a given substrate polarizer, in particular a polymer film , to form the second image.

As a remark, depending on the desired effect, the steps set out above will be carried out so as to form an image which is the positive or negative image of the second image. In particular, it is possible to apply locally to at least one polarizing filter, for example by printing, an aliphatic polyurethane polyether base, for example such as that sold by LAMBERTI under the name Esacote ^® PU 21 / S.

In the last possibility mentioned above, when during the implementation of the method according to the invention, the composition comprising cholesteric liquid crystals is between the polarizing substrate and the electronic imager, the cholesteric liquid crystals modify the polarized light. of the electronic imager which is not stopped by the substrate and the areas covered with cholesteric liquid crystals appear transparent when the polarizing substrate is oriented so as to be opaque.

On the other hand, when the polarizing substrate is between the cholesteric liquid crystal composition and the electronic imager, the cholesteric liquid crystals exhibit an optically variable effect when the polarizing substrate is oriented opaque. The optically variable effect of the cholesteric liquid crystals is more generally known by the term "colorshift" effect, the color of the cholesteric liquid crystals being dependent on the angle of observation and these being especially observed on a dark background, preferably from black color. The "colorshift" effect of the cholesteric liquid crystals may constitute additional security for authenticating and / or identifying the secured article.

Thus, in particularly preferred embodiments of the method according to the invention, the second image is defined by a first polarizing material superimposed on a second polarizing material, the first material extending in particular in patterns corresponding to the second image. and the second material extending continuously. The first material is preferably a cholesteric liquid crystal print and the second material is preferably a linearly polarizing substrate.

By "patterns corresponding to the second image" is meant that said patterns form the second image in negative or in positive.

Advantageously, when the first and second images have polarization properties, there is only one orientation of the one relative to the other allowing one to partially mask the other. In other words, there is only one orientation of the first image with respect to the second image to not being able to observe the first image through the polarizing zones of the second image, or vice versa. Indeed, the first and second images exhibiting polarization properties consist of polarizing zones and non-polarizing zones. When placed in front of a light source emitting polarized light, there is only one orientation in which the polarizing areas become opaque.

In particular, in the case where the article comprises a polarizing filter there is for example only one orientation of the second image relative to the first image projected or displayed by the electronic imager by means of a polarized light , which allows the polarizing filter to mask the polarized light of the electronic imager. The polarizing filter may appear opaque, in particular of black color, in this orientation, preferably unique, of the first image relative to the second image.

The presence of a single orientation of the first and second images relative to each other as described above can make it possible to authenticate and / or identify the secured article according to a first security level.

The electronic imager, for example the screen of the electronic imager, and / or the secure article may include an indicator for informing the user on the positioning the first and second images relative to each other to obtain said orientation, for example a visual cue.

According to an alternative embodiment, the second image is printed with a compound, in particular liquid crystals, visible only when placed in front of an electronic imager emitting polarized light, in particular a liquid crystal screen. Advantageously, the second image is transparent under unpolarized illumination, for example under natural lighting, and is visible only under polarized illumination with the aid of the electronic imager, which provides additional security for the secure article.

The secure article may comprise an integrated microcircuit, for example an RFID chip or an optical chip (activated for example by the light emanating from the electronic imager), capable of communicating with the electronic imager for it to produce, in particular displays and / or projects, informative information on how to position the first and second images relative to each other to obtain said orientation.

The secure article may comprise an integrated microcircuit, for example an RFID chip or an optical chip, capable of communicating with the electronic imager so that it produces at least one first image whose association with the second image makes it possible to put implement the method according to the invention. In particular, the electronic imager can produce at least a first image associated with a second image of the secured article by communication between the electronic imager and the integrated microcircuit.

The electronic imager can still produce at least a first image from a photo and / or video of the secured article, in particular the second image of the secured article or an identifier present on the article, for example a logo or serial number. The photo and / or video can be made with the electronic imager, an image capture device, for example a digital camera, connected to the electronic imager by a wire link or not and / or be transferred to the imager electronic, for example from a data storage device or via a network, such as the Internet.

The first image can be produced only from the photo and / or video of the secured article, or alternatively, be produced from the photo and / or video of the secure article and additional information, by example information present on the secure article, on the photo and / or video, entered by the user, or received from a network, for example from a secure server.

The electronic imager may comprise a program making it possible to identify the secure article, and in particular the second image, and to produce, in particular to display and / or project, a first image obtained from a database providing information. on the first image to be used according to the secure article, in particular the second image.

The electronic imager may produce a plurality of first images and / or the secure article may include a plurality of second images, at least one of the first images for observing the authentication and / or identification information when superimposed on least one of the second images according to the method of the invention, or vice versa.

In particular, it may thus be possible to authenticate and / or identify the security article with different types of electronic imagers.

As a variant, a given electronic imager can make it possible to authenticate and / or identify secure articles of different types, notably comprising second different images.

For example, the second images differ in size, color, shape, or even spacing between the nested frame elements or images or the width thereof.

The first images can also be differentiated by their size, color, shape, or even the spacing between the elements of the frame or nested images or the width of the latter, or even by the size of the pixels, the spacing between the pixels or the color of the pixels.

Electronic imagers can for example be differentiated by their brand, their model, their resolution, their type, namely computer screen, TV or telephone, or projector, for example.

The presence of several first images and / or second images may make it possible to authenticate and / or identify the security article independently of the differences mentioned above.

The first image produced by the electronic imager may come from a communication network with which the electronic imager communicates, for example a telephony network, the Internet or an internal network, the image being for example downloaded, and / or supplied with the electronic imager, for example on a data carrier, for example a hard disk, a USB key, a CD and / or a DVD. The security article may, where appropriate, include such a data carrier. The data carrier may be an integrated microcircuit, for example an RFID or optical chip, communicating with the electronic imager.

The secure article may include a luminescent zone, for example fluorescent and / or phosphorescent, and the electronic imager may project the first image on the secure article under ultraviolet (UV) illumination.

In particular, the second image may be a luminescent printing, for example made on a black opaque background of the secure article, on which the first image is projected under UV light. The second image is visible only under UV light.

The second image can still be printed on a luminescent background of the secure article, so that it is visible both under UV light and normal lighting.

Process

The subject of the invention is also a method for authenticating a secure article according to the first and second aspects of the invention, in which the image or images revealed by the revelation screen are observed, the angle of observation and / or position of the revelation frame with respect to the combined image to observe a change in the revealed image, and the authenticity of the article is concluded at least on the basis of this observation.

In the case where the combined image and the revelation frame or frames are not superimposed within the article, the revelation frame may be at least partially superimposed on the combined image to observe the images by folding the article. secure and / or by superimposing the secure article and the other object, changing the viewing angle and / or the position of the revelation frame relative to the combined image to observe a change of the revealed image and one concludes as to the authenticity of the article at least on the basis of this observation.

When one of the revelation frame and the combined image is formed by an electronic imager, the method may comprise at least one of the following steps: superimposing at least partially the second image of the article with a first image formed by the electronic imager to allow observation of authentication information and / or identification of the secure article.

superimposing at least partially the second image of the article with a first image produced by the electronic imager following a communication between the integrated microcircuit and the electronic imager,

superimposing at least partially the second image of the article with a first image produced by the electronic imager from a photo and / or video of the secured article, in particular from the first image,

The photo and / or video can be made with the electronic imager, an image capture device, for example a digital camera, connected to the object and / or transferred to the electronic imager, for example from a device data storage or via a network, such as the Internet.

The invention will be better understood on reading the detailed description which follows, examples of non-limiting implementation thereof, and on examining the appended drawing, in which:

FIG. 1A illustrates the formation of a combined image,

FIG. 1B is an enlarged detail of FIG. 1A,

FIGS. 2A to 2C show a succession of revealed images as it can be observed when the observation conditions vary,

FIGS. 3A to 3C represent a variant of revealed image succession as it can be observed when the observation conditions vary,

FIG. 4 illustrates a combined image variant,

FIGS. 5A to 5D represent a succession of revealed images such that they can be observed using the combined image of FIG. 4, when the observation conditions vary,

FIG. 6 represents a combined image variant,

FIGS. 7A to 7H show variants of revelation frames,

FIG. 8 represents in section, schematically and partially, an example of a secure article produced in accordance with an exemplary implementation of the invention, FIG. 9 illustrates the possibility of varying the inclination by deforming the secured article,

FIGS. 10 and 11 represent two examples of secured articles according to the invention,

FIGS. 12A to 12D show other examples of secured articles according to the invention, in cross-section, schematically,

FIGS. 13 and 14 illustrate variant embodiments of secured articles according to the invention, in cross section, schematically,

FIGS. 15 and 16 show exemplary embodiments of the secure article according to the invention, the combined image or the revealing frame being carried by a window of the article,

FIG. 17 represents the folded secure article,

FIGS. 18 and 19 show exemplary embodiments of secure article according to the invention, the combined image or the revelation frame being carried by a security thread,

- Figures 20 to 23 show other embodiments of secure articles according to the invention, the combined image and / or the revelation frame being carried by at least one safety wire or foil.

FIGS. 24 to 26 represent variants of assemblies comprising an electronic imager and an article,

FIG. 27 represents a variant of first images formed by an electronic imager,

FIG. 28 represents an article variant comprising an integrated microcircuit, and

FIG. 29 represents an overall variant, the article comprising a second image in the form of a revelation screen and an electronic imager producing a first image in the form of a combined image,

FIG. 30A represents another example of a combined image,

FIG. 30B represents a variant with a revealing frame in the form of pixels, and

FIGS. 30C to 30E show a succession of revealed images as can be observed using the combined image of FIG. 30A and FIGS. Figure 30B reveals when the viewing angle varies and / or the relative position of the revelation frame and the combined image varies.

Combined image

FIG. 1A illustrates an example of forming a combined image I by adding a plurality of nested images h, h, L. Each nested image L is formed of nested image lines ii arranged periodically according to FIG. Xi direction and the same width li constant over their entire length. The nested images are of the same period S.

As illustrated in FIG. 1B representing a detail of the combined image, the lines of the nested images ii to i _n comprise micromotives 7 as illustrated in FIG. 1B, in particular are formed by micromotives 7. The micromotives 7 of the lines ii of a nested image L can be identical.

Preferably, the micromotives 7 of the lines ii to i _n belonging to different imbricated images are of different aspects, in particular of different shapes and / or different hues, opacities, luminescences, glosses and / or saturations. Preferably, the micromotives 7 of lines ii to i _n belonging to different nested images are of different shapes, for example represent different alphanumeric signs and / or are of different hues, opacity, saturation, luminescence or gloss, for example of colors. different.

Preferably, the micro-patterns 7 are of the width / lines ii of the nested image and of a height of the same order of magnitude so that, in view of the resolution, the lines ii appear in a homogeneous color, the micromotives 7 not being distinguishable to the eye. The user must for example use a magnifying glass to view the micromotives 7, which enhances the security of the article.

For example, the micromotives 7 of the lines ii of a nested image may be of a certain hue so that the lines ii appear stained homogeneously.

The micromotives 7 can be positive or negative.

Micropatterns can represent alphanumeric characters, numbers, text, geometric shapes, objects, people or animals.

Such micro-patterns 7 make it possible to reinforce the security of the article 10 because they form additional security elements hidden in the lines that are not visible to the naked eye. In addition, the lines are more difficult to counterfeit because they require a resolution to manufacture, including printing, high.

In the example illustrated in FIG. 1B, the combined image I is formed of three nested images I ₁ , I ₂ and I ₃ each comprising nested image lines ii, i ₂ or 13 having colored micromotives 7. The lines ii of the first nested image Ii consist of a repetition of the red positive write "100", the lines 12 of the second nested image I2 are formed of a repetition of the word "AWS" in positive write of green color and the lines 13 of the third nested image I3 are formed of a repetition of the word "BUTTERFLY" in blue positive writing. With the naked eye, the lines ii appear red, the lines i ₂ appear green and the lines 13 appear blue, the micromotives "100", "AWS" and "BUTTERFLY" are not visible.

In the rest of the figures, the micromotives 7 of lines ii to i _n are no longer shown. The lines ii to i _n are represented as lines of homogeneous appearance but it should be understood that they have micromotives 7 as described above.

The nested image lines ii are parallel longitudinal axes defining a general orientation Oi of the image combined by their general direction. The periodicity is observed along an axis Xi perpendicular to the longitudinal axis of the nested image lines.

The combined image I corresponds to the superposition of these nested images Ii to I _n by shifting them relative to each other along the axis Xi so that the nested image lines ii to i _n are not superimposed between the different images.

The widths at _n of the lines of the nested images ii to i _n are such that the sum of the widths at _n of these lines ii to i _n is less than or equal to the period S, and preferably equal to the period S:

In the illustrated example, the lines of a nested image ii to 13 are of the same width at I3 equal to S / 3.

Alternatively, the lines ii to i _n of the nested images may be of different widths to l _n relative to each other, as shown in FIG. 6. In the example of FIG. 1A, the combined image I is formed of three nested images Ii to I ₃ . The first nested image Ii is formed of a periodic red line ii, the second nested image I ₂ is formed of a periodic green line i ₂ and the third nested image I ₃ is formed of a periodic blue line 13. The three lines of nested images ii to 13 are of the same width. The lines of nested images ii to 13 are rectilinear. The resulting combined image I is a raster image having periodic alternation of lines ii to 13 of different colors.

The period S is between 10 μιη and 1 mm, preferably between 50 and 200 μιη.

The width / lines of nested images ii to i _n are less than or equal to

50μιη, being for example substantially equal to 33 μιη. This value corresponds to a resolution of the combined image I of about 800 dpi, which is a limit for conventional printers which generally have a maximum resolution of 600 dpi, and which constitutes a safety factor.

Moreover, the human eye not perceiving at an observation distance greater than or equal to 30 cm the details less than approximately 100 μιη, a sufficiently fine combined image appears of homogeneous appearance, for example substantially white here in transmitted light.

Also, regardless of the color or colors used for the combined image, the print definition may be accurate enough that the color mixing appears as homogeneous.

Revelation frame

In the example illustrated in FIGS. 2A to 3C, the revealing frame 4 is composed of a periodic alternation of constant Q period of straight and occulting line lines 5a, in particular of black opaque lines, and of non-blackout lines 5b. , in particular transparent lines of parallel longitudinal axes. The periodicity is observed along an axis Χτ perpendicular to the longitudinal axis of the weft lines 5a and 5b.

The longitudinal axes of the weft lines 5a and 5b define a general orientation of the frame Ot by their general direction.

The opaque raster lines 5a are of a constant width m less than the period Q of the frame and the transparent raster lines 5b are of a constant width k, smaller than the period Q. The widths of the opaque field lines 5a and 5b transparent field lines may be identical or not.

In the example illustrated, the lines of fields 5a and 5b are with straight and parallel edges, but it may be otherwise. The revealing frame 4 may comprise other patterns such as crenellations or corrugations, as illustrated respectively in FIGS. 7A and 7B.

The resolution of the revealing frame 4 is preferably greater than or equal to 800 dpi.

The revelation screen 4 can be as such of homogeneous appearance to the naked eye at a normal viewing distance, given its fineness. In particular, the revealing frame may appear to the naked eye 15 cm apart as having a uniform gray color, more or less dark depending on the width m of the opaque raster line 5 a.

A combined image and a revelation frame sufficiently fine to provide anti-photocopying security

The combined image I and / or the revelation screen 4 may be formed by printing, metallization, demetallization, laser marking, lithography or any other technique for fixing or displaying an image.

To improve security, it is possible to use liquid-crystal inks, for example to print the combined image I. The animation, to be revealed, may then require in addition to the revelation screen, the use of a filter polarizer, which may be present on the article, or not.

The revelation screen 4 may be formed by printing or metallization and / or demetallization.

The opaque raster lines 5a of the revelation weft 4 may be shiny or matte.

In a non-illustrated variant, the opaque lines of the revealing frame may comprise micromotives such as those described with reference to FIG. 1B.

In a variant, the revelation frame 4 is different, especially the lines of frames are not opaque and transparent. The blackout frame lines may be formed of a filter that does not allow the wavelengths corresponding to the combined image to be passed and the lines of non-occulting frames can pass these wavelengths at least partially. Revealed image

The period Q of the revelation frame 4 is equal to the period S of the combined picture I.

When the revelation screen 4 and the combined image I are superimposed and the general orientation Ot of the revelation screen 4 is substantially the same as the general orientation Oi of the combined image I, a revealed image I _r can to be observed. The revealed image I _r then corresponds to the parts of the combined image I present under the lines of transparent frames 5b for a given observation angle.

Indeed, when the revelation frame 4 and the combined image I are superimposed, in the aforementioned condition and when the revealed images are observed on the side of the revelation frame, the opaque screen lines 5 have masked part of nested picture lines ii to i _n , the other part of the nested picture lines ii to i _n being visible through the transparent picture lines 5b. The lines of transparent frames 5b all allow the display of the same proportion (Pi; ..; P _n ) of the nested image lines ii to i _n . The proportion Pi corresponds to the proportion of a line ii of the visible nested image L.

In the case where the superposition is observed on the side of the combined image I, the lines of opaque fields 5a render the nested lines of images ii to i _n on which they are superimposed dark and thus prevent their visualization. Thus, only the nested image lines ii to i _n superimposed on the lines of transparent frames 4b are visible to form the revealed image I _r .

Preferably, the revealed images I _r are observable in reflected light and transmitted light.

Colorful picture

In the example of FIGS. 2A to 2C, the nested image lines ii to i _n are all of the same width at 1 _n and the opaque screen lines 5 a have a width m equal to twice the width of the lines of nested images ii to i _n . Thus, the opaque raster lines 5a, when properly positioned relative to the nested image lines ii to i _n , overlap two nested images, two colors, and only one nested image, one color, is visible . In the case of FIG. 2A, all the blue is visible and all the red and the green are hidden, the proportion (Pi; ..; P _n ) of the nested image lines ii to i _n of the revealed image I _r is (0; 0; 1). Similarly for Figure 2B, the proportion (Pi; ..; P _n ) of nested image lines ii to i _n of the revealed image I _r is (1; 0; 0) and for Figure 2C the proportion (Pi; .. P _n ) nested picture lines ii to i _n of the revealed picture I _r is (0; 1; 0).

Alternatively, in the example of FIGS. 3A to 3C, the nested image lines ii to i _n are all of the same width at 1 _n and the opaque screen lines 5 a have a width m equal to 0.75 times the width of nested picture lines ii to i _n . Thus, the opaque raster lines 5a, when properly positioned relative to the nested image lines ii to i _n , cover three quarters of one of the nested images, three-quarters of one color; two nested images and a quarter of the third nested image are visible. In the case of Figure 3A, all the blue and green and a quarter of the red are visible and three quarters of the red is hidden, the proportion (Pi; P ₂ ; P3) nested lines of images ii, i ₂ and 13 of the revealed image I _r is (0.25; 1; 1). Likewise for FIG. 3B, the proportion (Pi; P ₂ ; P ₃ ) of the nested image lines ii, i ₂ and 13 of the revealed image I _r is (1; 0.25; 1) and for FIG. 3C, the proportion (Pi; P ₂ ; P ₃ ) of the nested image lines ii, i ₂ and 13 of the revealed image I _r is (1; 1; 0.25).

The revealed image L can appear homogeneous with the naked eye. In the case of a combined image I in the form of a colored frame formed of an alternation of red, green and blue lines of identical widths / and of a transparent frame line width revealing frame k, It is possible to determine the color of the revealed image I _r in RGB coordinates from the proportion (PR, PV, PB). The RGB coordinates are in the form of three numbers between 0 and 255 characterizing said color, each number each representing the proportion of one of the red, green and blue components for obtaining said color.

The components have the following coordinates:

R = Rjnax * PR>

ν = Vmax * Pv, and

B ⁼ Bmax * ¾ i

with R _max = V _max = B _max = 255 * ^ ^

It is thus possible to determine the color of the revealed image as a function of the width k of the lines of transparent frames 5b and the proportion (PR, PV, PB) of the nested images Ii, I ₂ and I3. The revealed image Ir is observable in transmitted light or in reflected light both on the side of the revelation screen 4 and on the side of the combined image I when the revelation screen 4 and the combined image I are superimposed.

Revealed image as a pattern

In the variant, illustrated in FIGS. 4 to 5D, each nested image Ii to I _n comprises a periodic alternation of continuous or discontinuous lines as described above, forming a pattern, for example as shown in FIG. 4. The pattern may represent a text, alphanumeric signs, ideograms, an object, a person, a plant, a monument and / or an animal. The lines of transparent frames 5b are of width k equal to the width / of a line of nested images. Thus, the revealed image corresponds to one of the interleaved images and can, as illustrated in FIGS. 5A to 5D, allow the observation of at least one pattern of the revealed imbricated image. A change in the observation conditions corresponding to a relative displacement of the revealing frame 4 relative to the combined image I along the X axis and / or a change in the observation angle of the revealing frame 4 and of the combined image I can make it possible to observe successively the different nested images Ii to I _n , which can make it possible to give a movement effect when the nested images Ii to I _n each represent the decomposition of a motion.

In the example of FIGS. 4 to 5D, the combined image I comprises four nested images Ii, h, h and I ₄ representing different positions of a revolving spiral, as represented in FIG. 4. The nested image lines ii, i ₂ , 13 and i ₄ are discontinuous. The revelation frame 4 makes it possible, when superimposed on the combined image in the same orientation, to observe the spiral of one of the nested images 11 to ₁₄ , as illustrated in FIG. 5A.

In the variant illustrated in FIG. 30A, the combined image I comprises a periodic alternation of nested image pixels pi to p _n along two X and Y directions. The nested image pixels pi to p _n are rectangular in shape but it could be otherwise. For example the pixels could be of another polygonal shape, including square, triangle, hexagon or rhombus.

The pixels of FIG. 30A can also be seen as diagonal nested image lines formed of pixels joined together by one of their corners periodically alternating along the Z direction. The foregoing description, for lines, applies to pixels. Thus, the pixels pi to p _n belonging to different nested images have a different appearance, including hue, saturation, brightness, transparency, a different luminescence. For example, the pixels pi to p _n belonging to different nested images are of different colors, in particular red, green and blue.

The combined image I has in the direction Xi a period Sx and in the direction Yi a period SY. Here, the directions Xi and Yi are perpendicular but it could be otherwise. The directions Xi and Yi could form between them a non-zero angle and different from 90 °.

The nested image pixels pi to p _n have a dimension 1χ and a dimension 1γ respectively along the directions Xi and Yi. The dimensions lx and 1γ are each as previously described for the nested picture lines ii to i _n .

The revealing frame 4 is according to FIG. 30B. It has a periodic alternation of opaque frame pixels 5a in two directions Χτ and Υτ forming between them the same angle as the directions Xi and Yi. The opaque frame pixels 5a are separated from each other by transparent intervals 5b and are repeated according to the periods Sx and SY of the combined image according to the respective directions Χτ and Υτ.

The pixels of the revelation frame may be of dimension mx and dimension my according to the respective directions Χτ and Υτ less than periods Sx and SY respectively.

In the illustrated example, the dimension mx in the direction Χτ is equal to the dimension lx of the nested image pixels pi to p _n and the dimension my in the direction YT is equal to the dimension 1γ of the nested image pixels pi at p _n .

The dimensions mx and my can be different from lx and 1γ, respectively, provided that the periods of the revelation screen 4 and the combined image I are the same in each of the X and Y directions.

During the superimposition of the revelation screen 4 and the combined image I so that the directions Χτ and Xi coincide and the directions YT and Yi coincide, the revelation frame makes it possible to observe the revealed images I _r such that shown in Figures 30C-30E.

In the example shown, the opaque frame pixels 5a hide one of the nested images Ii to I _n so that two of the nested images are visible. On the FIG. 30C, the revealed image I _r is formed of the green and red nested images, in FIG. 30D the revealed image I _r is formed of the blue and red nested images and in FIG. 30E the revealed image I _r is formed blue and green nested images.

The different illustrated images I _r illustrated can be obtained by moving the revealing frame 4 relative to the combined image in the direction Xi, the direction Yi or direction Z and / or by changing the angle of view around the images. Xi, Yi or Z directions.

Observation of a change in the revealed image

It is possible to vary the revealed image I _r observed by changing the observation conditions of the superimposition frame 4 and the combined image I superimposed, and in particular, as is detailed later, by changing the viewing angle and / or moving the revealing frame 4 relative to the combined image I. Thus, virtually or actually, by moving the combined image I with respect to the revealing frame 4 in the direction X of alternating weft lines and combined image lines, the revealed image L varies.

By changing the viewing conditions, it is possible to move from Figure 2A to Figure 2B and Figure 2C. It is the same for Figures 3A to 3C and for Figures 5A to 5D.

By varying the observation conditions, the user can then see a change in the image revealed I _r and conclude in view of this observation on the authenticity of the article.

In the case where the nested images are as described in relation with FIGS. 4 to 5D, the displacement of the revelation frame 4 with respect to the combined image I along the X axis makes it possible to successively observe the various nested images. Ii to I ₄ , which gives the impression to the user that the spiral rotates about its central axis.

Observation by superposition on both sides of a support

FIG. 8 shows a first embodiment in which a secure article 10 according to the invention comprises a non-opaque substrate 20, for example perfectly transparent, having a first face 20a carrying the combined image I. The second face 20b of the substrate 2, opposite the first, carries the revealing frame 4. When the secure article 10 is observed on one side or the other of the substrate, the revelation screen 4 makes it possible to observe one or more images revealed I _r . By changing the observation angle a, the user changes the observation conditions and the revealed image (s) I _r are modified as previously described. For the eye, a change in the viewing angle corresponds to a relative displacement of the revealing frame 4 relative to the combined image I.

In order to be able to view all the nested images at an angle of inclination of about 45 °, the thickness e of the substrate is preferably greater than or equal to approximately the period Q.

For example, if a frame of period g at 100 μιη is used, the thickness e of the substrate is greater than 100 μιη.

It may be advantageous to have a substrate whose thickness e is less than or equal to 30 μιη, better 25 μιη, for example between 20 and 30 μιη, or even 20 and 25 μιη, limits included or excluded.

Another possibility for varying the observation direction of the secure article may be to deform the substrate, for example around a folding axis, as shown in FIG. 9.

Since the optical system can operate in transmitted or reflected light, it can be used for windows or wires introduced into windows, for example in a banknote.

Depending on the pattern of the revelation screen 4, a registration of the latter with respect to the combined image I may be necessary, especially in the direction parallel to the general orientation of the latter. For example, for a linear revelation frame as illustrated in Figure 2, no registration is necessary; on the other hand, for a corrugated frame, a more or less precise location, depending on the amplitude and the frequency of the corrugations, may be desirable. The invention thus offers a possibility of modular security depending on the protection requested and the difficulty of implementation.

For secure articles comprising a wire introduced into window (s), the combined image I can be obtained by micro-photolithography of the wire and the revelation screen 4 can be achieved by means of offset printing with UV crosslinking inks made in a second time, when printing the article. The revelation frame 4 may be associated, where appropriate, with a print pattern of the article.

The pattern of the revelation screen 4 may be printed elsewhere than in superposition with the combined image I, on the article, on the same scale or on a different scale.

The printing of the revealing frame 4 may overflow the combined image I and extend over the secure article 10, as illustrated in FIG.

Several revelation frames and combined images, for example having the shape of small squares or rectangles of a few millimeters of sides, may be present on the same security thread 30, as illustrated in FIG. 11.

When the revealing frame 4 and the combined image I are on a window integrated wire (s), as illustrated in FIGS. 12A and 12B, the secured article 10 may comprise at least two windows 31 and 32 making it possible respectively to observe each of the faces of the wire, in reflection.

The substrate of the article may comprise, at the level of the windows 31 and 32, material gaps and transparent zones 35 and 36 enabling observation of the images revealed on both sides of the secured article 10.

The nested images are observable through the revealing frame 4 on the side of the window 31 and with the revealing frame as a background, on the side of the window 32.

Article 10 may also include a through window 31, as shown in Figure 12D, the revelation frame 4 and the combined image I being located at least partially in this through window. In this way, it is possible to observe the revealed images of both the front side and the back side of the secure article 10.

The revelation frame 4 and the combined image in the form of a security thread may further be incorporated into a secure article 10 which has alternating front and back side windows 31 and 32 as shown in Fig. 12C. It is thus possible to observe the images revealed both from the front side and from the back side of the secure article 10 at the level of the windows 31 and 32, and in particular because of the presence of the material gaps and the transparent areas 35 and 36. FIG. 13 shows an example of a secure article 10 comprising a perforation 40 in which at least two sub-elements are placed, in particular in the form of foils or patches, 41 and 42.

The sub-element 41 comprises for example a revelation frame 4 and the sub-element 42 comprises for example the corresponding combined image I.

The sub-elements 41 and 42 can be superimposed at least partially on the borders of the perforation 40 with or without a thickness compensation.

Sub-elements 41 and 42 may be at least partially transparent or translucent.

The observation of the revealed images can be done by observation in reflection or in transmission, for example using a light source located behind the article 10 during the observation.

In the variant illustrated in Figure 14, the secure article 10 comprises a combined image I made in the form of prints. The prints are for example made on the surface of the secure article 10. In addition, a sub-element 43, in particular in the form of a foil or patch, is placed on the prints constituting the combined image I, the sub-element 43 comprising the corresponding revelation screen 4, for example made on the surface of the sub-element 43.

The secure article 10 may be opaque or not. The secure article 10 may be at least partially transparent or translucent to allow the observation of the nested images, especially on the side of the combined image I.

In the examples of FIGS. 13 and 14, the revelation frames 4 and / or the combined images I could be made differently, for example being incorporated or located above or below the sub-elements 41, 42 and 43.

As a variant, the combined image comprises two metallizations of different colors, each corresponding to an interleaved image, in particular an interleaved copper image and an interleaved aluminum image.

As a further variant, the combined image comprises at least two metallizations, in particular of the same color, of different optical densities, each corresponding to a nested image, thus creating a contrast of brightness.

The imbricated aluminum image can be of high optical density, which gives it a brilliant appearance. The revelation weft 4 may be matte in appearance.

The superimposition of the combined image I and the revelation frame 4 makes it possible to obtain revealed Li to I _rg mats or glossy images.

Observation by folding the document or overlaying the document and another object

In a second embodiment, illustrated in FIG. 15, the secure article 10 comprises a window 50, preferably at least partially transparent, in which the revealing frame 4 is shown. Article 10 also includes a combined image. on the article 10, for example by printing, including printing intaglio, offset printing or metallization and / or demetallization. The area on which the combined image 2 appears may also be at least partially transparent.

To observe the revealed image, the user must therefore fold the secure article 10, as illustrated in Figure 17, to bring the revelation frame 4 to the combined image I so that their general orientation is the same and observe the image or images revealed L. Thus, the revealed images are not visible when the article 10 is not folded and it requires an action of the user, namely to fold the secure article 10, to make them appear. This strengthens the security of Article 10.

In FIG. 16, the secure article 10 comprises a window 50, preferably at least partially transparent, in which the combined image I appears. Article 10 also includes a patch 55 comprising, for example, holographic impressions, on which FIG. the revelation screen 3. The patch 55 can also be at least partially transparent.

The patch 55 may comprise metallizations and / or demetallizations, for example made of aluminum, and the revelation screen 4 may comprise holographic impressions and / or metallizations and / or demetallizations.

In FIG. 18, the article 10 comprises a window 50, preferably at least partially transparent, on which the revealing frame 4 appears. The article 10 also comprises a security thread 60 on which the combined image I. The security thread 60 may also be at least partially transparent or comprise a partially transparent zone at the combined image I.

FIGS. 19 to 23 show further examples of secure article 10 according to the invention comprising a combined image I and a revelation frame 4 that conform to FIG. to those of Figures 15 and 16, the combined image I and / or the revelation frame 4 being carried by at least one safety wire or foil.

In FIG. 19, the article 10 comprises a security thread 60 of sufficient width to alternately display combined images I and revealing frames 4. Advantageously, the security thread 60 is at least partially transparent or present one or more areas at least partially transparent at the combined images I and / or the revelation frames 4.

In FIG. 20, the article 10 comprises a security thread 60 on which a revealing frame 4 appears. The article 10 also comprises a combined image I, for example in the form of an offset printing on the article 10 .

The security thread 60 may be at least partially transparent or have an at least partially transparent area. Article 10 may also include an area at least partially transparent at the combined image I.

In Fig. 21, article 10 has two security threads 60a and 60b. The security thread 60a comprises three combined images I and the security thread 60b comprises three revelation frames 4.

The security thread 60a and / or the security thread 60b may be at least partially transparent or comprise at least one at least partially transparent zone, in particular at a combined image I or a revelation screen 4.

In FIG. 22, article 10 comprises a foil 70 on which there is an alternation of combined images I and of revelation frames 4.

The foil 70 may be at least partially transparent or comprise at least one at least partially transparent zone at a combined image I and / or a revelation screen 4.

In FIG. 23, the article 10 comprises a security thread 60 on which a combined image I appears. Article 10 also comprises a patch 55, which may comprise holographic or non-holographic metallizations, on which there is a revelation screen 4.

The security thread 60 may be at least partially transparent or comprise an area at least partially transparent at the combined image I.

The patch 55 may also be at least partially transparent, especially at the level of the revealing frame 4. In all the examples previously described, the combined images I and the revelation frames 4 can be inverted.

The at least partially transparent areas may be located at the combined images I or at the revelation means 4, or both.

The security son or son 60, 60a and 60b can be introduced into the secure article 10 in a conventional manner, for example at the surface, in the mass or in the window (s).

The authentication of the articles 10 can be done by folding the articles 10 lengthwise or widthwise so as to superimpose at least partially the combined images I and the revelation fields 4, and then relatively to move relative to each other. to the others so as to visualize for example the illusion of a movement and / or to modify the angle of observation of the combined images I and superimposed revelation fields 4.

In another variant, it is also possible to at least partially superpose the article 10 with another similar article as described above.

imager

FIGS. 24 to 26 show examples of association between a secure article 10 and an electronic imager 100 making it possible to form the revelation screen 4 or the combined image I.

In FIG. 24, the electronic imager 100 is for example a computer screen on which a first image 110 is displayed, the first image 110 being the revelation screen 4 or the combined image I.

The secure article 10 is for example in the form of a bill and has a second image 120, the second image being the revelation frame 4 if the first image is the combined image and vice versa.

The secure article 10 is placed on the screen of the electronic imager 100 so as to at least partially superimpose the first image 110 to the second image 120 to observe the revealed image (s) I _r and deduce therefrom an authentication information and / or identification of the secure article 10.

The secure article 10 may be moved relative to the screen of the electronic imager 100 or the observer may change viewing angle to allow observation of a change in the revealed image (s) I _r . In a variant, the secure article 10 with reference remains immobile with respect to the screen of the electronic imager 100 and the first image 110 is animated by a movement on the screen, for example a translation, for example at the using a program activated or not by the user.

In FIG. 25, the electronic imager 100 is for example in the form of a digital projector, projecting a first image 110 on a bottom 150, for example the wall of a room.

The secure article 10 comprising the second image 120 can then be superimposed at least partially on the first image 110 projected on the bottom 150 to allow the observation of the revealed image (s) I _r .

In FIG. 26, the electronic imager 100 is a projector that projects the first image 110 directly onto the secure article 10.

The first image 110 may, as in the example of FIG. 26, be projected, for example in the form of a "W", on an area of the secure article 10 where the second image 120 is not present. the secure article 10 is for example folded on itself so as to superpose the second image 120, for example in the form of "A", the first image 110 projected by the electronic imager 100. The part of the article secure 10 comprising the second image 120 may in particular be folded over the portion comprising the first image 110, this portion remaining stationary, so that the first image 110 is between the imager 100 and the second image 120.

In a variant, not shown, the first image 110 is projected directly onto the second image 120 of the article 10. In particular, the projection of the first image 110 on the second image 120 of the article 10 may allow an overlap with the less partial of the first and second images. Then, the electronic imager 100 can be moved relative to the article 10 to move the revealing frame 4 relative to the combined image I.

FIG. 27 shows a variant embodiment in which the electronic imager 100 is a screen displaying several first images 110a, 110b, 110c and 10d.

The first images 110a to 1 10d may have different properties, for example shapes, colors, dimensions, elements, in particular points or lines, of different wefts. Advantageously, the first images 110a to 10d differentiate so as to allow at least one of them to be associated with at least one second image 120 present on an article 10. In this way, it is for example It is possible to authenticate and / or identify a greater diversity of articles having respective different second images, corresponding to different first images 110a-1d.

In a variant, the article 10 comprises several different second images 120, as can be seen for example in FIG. 11, and the electronic imager 100 produces one or more first images 110. In this way, it is possible, for example, to to authenticate and / or identify a given security article 1 on a larger diversity of different electronic imagers, and in particular with electronic imagers having different resolutions. In this way, the two advantages described above can be combined.

The electronic imager 100 may display one or more indicators 140a, 140b, 140c and 140d for informing the user on how to position the article 10 shown in Fig. 28 relative to the imager.

In particular, the indicators 140a to 140d can make it possible to know where to position the upper right corner of the article 10, so as to superimpose correctly a second image 120 of an article 10 to a first image 110a, 110b, 110c or l 10d displayed on the electronic imager 100 screen.

Article 10 may comprise an integrated microcircuit 152, for example a chip

RFID or optical, for communicating with the electronic imager 100 to control the display of an indicator as described above or to disseminate information on how to position the first and second images.

As a variant, the chip 152 is able to communicate with the electronic imager 100 to enable the first image 110 associated with the second image 120 to be produced.

In particular, during the method of authentication and / or identification of the article 10, the second image 120 is illuminated with the electronic imager 100. The chip 152 includes information transmitted to the electronic imager 100 which projects or then displays the first image 110 based on this information.

Article 10, in particular the second image 120, can be photographed and / or filmed by a digital camera belonging to or connected to the electronic imager 100. A recognition program can then make it possible to recognize the second image 120 and to acquire from a database a first image 110 associated with the second image 120. The database is for example stored on a secure server. The first image 110 thus obtained is displayed and / or projected by the electronic imager 110 to allow authentication and / or identification of the article 10.

As a variant illustrated in FIG. 29, the electronic imager 100 is in the form of a mobile phone on which a first image 110 is displayed in the form of a combined image I. Article 10 comprises a polarizing filter on which a the second image 120 is formed as a revelation screen 4. The article 10 comprising the second image 120 in the form of a revelation screen 4 is superimposed on the first image 110 in the form of a combined image I produced by the electronic imager 100, this emitting a polarized light.

The article 10 comprising the revelation screen 4 can be displaced by a translation movement along the axis X relative to the combined image I displayed by the screen of the electronic imager 100, so as to change the the revealed images I _r .

Such a method makes it possible to authenticate and / or identify the security article 1 according to several security levels.

The positioning of the revelation screen 4 comprising the polarizing filter according to the orientation making it possible to observe the opacity of the polarizing filter, this observation being visible only on a screen emitting polarized light, for example an LCD-type screen, provides a first level of security.

The revelation of the animation of the images revealed by displacement of the revelation frame 4 relative to the combined image I provides a second level of security.

As a further variant, the electronic imager 100 is a screen, in particular of the LCD type, comprising a plurality of pixels preferably forming a combined image, for example as described in FIG. 30 A.

The invention is not limited to the illustrated examples. The secure article can be made with other first, second or third level security, for example.

The expression "comprising a" should be understood as being synonymous with "comprising at least one".

Claims

A secure article (10) having a revelation frame (4) and a combined image (I), or an assembly comprising a secure article (10) and another object (100), the secure article (10) including the one of the revelation screen (4) and the combined image (I) and the object (100) comprising or forming the other of the revelation screen (4) and the combined image (I),

the combined image (I) being composed of a plurality of nested images (Ii at each nested image (Ii to I _n ) and / or the revelation field (4) being composed of a plurality of elements (ii at i _n , p1 to p _n , 5a, 5b),

the revelation screen (4) allowing, when superimposed on the combined image (I), to observe different revealed images (I _r ) by displacement of the revelation screen (4) with respect to the image combined (I) and / or by changing the angle of observation a, the revealed images each having a certain proportion (Pi; ...; P _n ) of each nested image (Ii to I _n ), and

the elements (ii to i _n , pi to p _n , 5a, 5b) being composed of one or more micromotives (7),

the micro patterns (7) belonging to different nested images (Ii to I _n ) being different in their colors, hues, opacities, saturation or luminescence or brightness.

2. Article or assembly according to claim 1, all the elements (ii to i _n , pi to p _n , 5a, 5b) of all the nested images (Ii to I _n ) and / or the revelation frame (4) being composed of one or more micromotives (7).

3. Article or assembly according to claim 1 or 2, the nested picture elements (ii to i _n , pi to p _n ) and / or revealing frame (5a, 5b) being each composed of several micromotives (7) , in particular a micropod (7) repeating periodically in one or more directions over the entire dimension of the element (ii to i _n , pi to p _n , 5a, 5b) according to this or these directions.

4. Article or assembly according to any one of claims 1 to 3, the micromotives (7) having at least one dimension (1) less than or equal to 1 mm, better than or equal to 100 μιη, more preferably less than or equal to 50 μιη.

5. Article or assembly according to any one of the preceding claims, the micromotives (7) belonging to different imbricated images (Ii to I _n ) being different in their aspects, in particular their shapes, and having a contrast, especially a contrast of saturation, hue and / or luminance (L *), and / or a color difference sufficient to distinguish, in particular under white light, two adjacent nested image elements (ii to i _n , pi to p _n ) when they are observed with a certain magnification, for example with a magnifying glass.

6. Article or assembly according to claim 5, the micro patterns (7) belonging to different imbricated images (Ii to I _n ) being of different shapes and / or different colors, in particular different hues.

7. Article or assembly according to any one of the preceding claims, the micromotives (7) being represented in positive or negative.

8. Article or assembly according to any one of the preceding claims, the combined image (I) having a resolution greater than or equal to 800 dpi, better, greater than or equal to 1000 dpi.

9. Article or assembly according to any one of the preceding claims, the elements (ii to i _n , pi to p _n ) of the same nested image appearing of the same color but of a color different from those of the other nested images ( Ii to I _n ), the combined image (I) comprising at least three interleaved images (Ii, h, h) of preferably primary colors, in particular respective colors red, green and blue, and the revealed images (I _r ) being of a color depending on their proportion (Pi; P ₂ ; P ₃ ) in each of the nested images (Ii, I ₂ , 1 ₃ ).

10. An article or an assembly according to any one of the preceding claims, the nested image (I) comprising a periodic alternation of elements (ii to i _n , pi to p _n ) of imbricated images in one or more directions (X , Xi, Yi), each revealed image (I _r ) corresponding to a nested image (Ii to I _n ).

11. Article or assembly according to any one of the preceding claims, the revealing frame (4) comprising a periodic alternation of two weft elements (5a, 5b) in one or more directions, the two weft elements (5a, 5b). ) being different opacities, transparencies and / or hues, in particular one weft element (5a) being occulting, in particular opaque, and the other element (5b) being non-occulting, in particular non-opaque.

12. Article or assembly according to claim 10 and claim 11, being arranged such that when the revelation screen (4) and the combined image (I) are superimposed, the directions (X, Χτ, Υτ) in which the frame elements (5a, 5b) alternate periodically and the directions (X, Xi, Yi) in which the nested picture elements (ii to i _n , pi to p _n ) alternate periodically are identical.

13. Article or assembly according to any one of the preceding claims, being arranged so that the revealed images (I _r ) are observable in reflected light and / or transmitted light.

An article or assembly according to any one of the preceding claims, arranged so that the revealed images (I _r ) are observable both on the side of the revelation screen (4) and on the side of the combined image. (I).

15. Article or assembly according to any one of the preceding claims, the revealed images (I _r ) forming macromotifs having different aspects, in particular different colors and / or glosses, for example different RGB coordinates and / or different patterns. , especially the different stages of a movement.

16. Article or assembly according to any one of the preceding claims, at least one of the combined image (I) and the revelation screen (4) on an area of the secured article (10) or the at least partially transparent object, the superposition of the revelation screen (4) and the combined image (I) being effected by folding the security document (10) or by superimposing the security document (10) with the other object, the revelation screen (4) allowing, when superposed at least partially on the combined image (I) of the secured article (10) or the other object (100), to observe images revealed (I _r ) different by a relative displacement of the revelation screen (4) relative to the combined image (I) according to one or more directions of the combined image and the revelation frame.

17. Article or assembly according to any one of claims 1 to 16, the revelation screen (4) and the combined image (I) being superimposed by being separated from each other by a constant thickness interval, the interval being in particular formed by a transparent or translucent substrate (20) having on the side of a first face of the substrate (20a) the combined image (I) and on the side of a second face of the substrate (20b), opposite to the first, the revelation screen (4) superimposed on the combined image (I).

18. Article or assembly according to claim 17, being arranged in such a way that the revealing frame (4) makes it possible to observe different revealed images (I _r ) during a change in the observation direction of the article. secured.

An assembly according to any one of claims 1 to 18, the other object being an electronic imager (100) for forming a first image (110), the first image (110) being the revelation field (4) or the combined image (I), so that it can be superimposed on a second image (120) of the secured article (10), the second image (120) being the other of the revelation field (4) and the combined image (I).

20. A method of authenticating a secure article (10) according to any one of the preceding claims, wherein the revealed image (I _r ) is observed by the revelation screen (4), the angle d is changed. observation and / or position of the revealing frame (4) with respect to the combined image (I) to observe a change in the revealed image (I _r ) and concluding as to the authenticity of the article (10) in view of the change of image observed.