FR2976705A1 - Electronic authentication device for displaying identification information related to e.g. commercial product, has electrochromic display including power supply terminals providing supply voltage in presence of electromagnetic wave - Google Patents

Abstract

The device has an electrochromic display printed on a dielectric support e.g. paper, and a transponder connected to power supply terminals of the display, where the terminals provide a supply voltage to the display in the presence of an electromagnetic wave (18). The transponder is selected to operate when the frequency of the electromagnetic wave is between 800 Mega hertz and 5 Giga hertz. The transponder is selected to operate when the electromagnetic wave corresponds to a wave emitted by a cordless telephone (17) positioned in the vicinity of the device.

Description

B11016 1 ELECTRONIC DISPLAY DEVICE

FIELD OF THE INVENTION The present invention relates to an electronic device for displaying information, for example identification information, which can be associated with any object (commercial product, sensitive document, etc.) as a sign. of its authenticity. It is more particularly a device that can be read easily and without specific equipment. DISCUSSION OF THE PRIOR ART Radio frequency identification (RFID) type electronic tags, comprising an antenna coupled to an electronic chip, and capable of responding to queries emitted by a terminal, are known. remote reading. The chip contains an identifier, and the label can be associated with any type of object (commercial product, packaging packaging, spare part, document, etc.). A person equipped with a suitable terminal can read the identifier contained in the chip, to obtain for example information as to the provenance of the object.

A disadvantage of this type of label lies in the fact that it is necessary to have a dedicated reading terminal to identify the marked objects. This imposes a B11016

2 expensive equipment, and in particular does not allow any individual of the public, for example a customer of a supermarket, to verify itself the authenticity of an object. In addition, the cost price of the label itself is relatively high. In addition, there is a risk that the label is peeled off, or is fraudulently diverted to be associated with an object that would not be genuine. It would be desirable to have an electronic authentication device that does not require, for its reading, the use of a specific terminal. Furthermore it would be desirable to have an authentication device that is not likely to be easily diverted to be associated with non-genuine objects. Summary An object of an embodiment of the present invention is to provide an electronic authentication device at least partially overcoming some of the disadvantages of existing solutions. An object of an embodiment of the present invention is to provide such a device containing easily readable authentication information and without specific equipment.

An object of an embodiment of the present invention is to provide such a remote readable device. An object of an embodiment of the present invention is to provide such an inexpensive device to achieve.

An object of an embodiment of the present invention is to provide such a device easy to incorporate in any type of object or packaging that may be subject to an authenticity check. An object of an embodiment of the present invention is to provide such a device which is not B11016.

3 likely to be easily diverted for the purpose of being associated with non-genuine objects. Thus, an embodiment of the present invention provides an electronic information display device comprising: an electrochromic display printed on a dielectric medium; and a transponder connected to display power terminals, adapted to supply a supply voltage to the display in the presence of a suitable electromagnetic wave.

According to one embodiment of the present invention, the transponder is chosen to operate when said wave has a frequency between 800 MHz and 5 GHz. According to one embodiment of the present invention, the transponder is chosen to operate when said wave corresponds to a wave emitted by a wireless telephone positioned near said device. According to one embodiment of the present invention, the display comprises a pattern whose color changes when the display receives said supply voltage.

According to one embodiment of the present invention, the shape of the pattern is related to the shape of a layer made of an electrochromic material, this layer having a first color in the unpowered state, and a second color when said voltage of power supply is applied.

According to one embodiment of the present invention, the shape of the pattern is further related to the shape of a mask formed above the electrochromic layer. According to one embodiment of the present invention, the mask is printed using an opaque ink of said first color. According to one embodiment of the present invention, the transponder comprises an antenna and a rectifying diode, the antenna being printed on the dielectric support with a conductive ink.

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According to an embodiment of the present invention, the rectifying diode is a semiconductor diode carried on the dielectric support. According to one embodiment of the present invention, the dielectric support is a cellulosic carrier such as paper or cardboard. According to one embodiment of the present invention, the dielectric support is a part of a packaging package. Another embodiment of the present invention provides a packaging package provided with an electronic information display device of the aforementioned type. Another embodiment of the present invention provides a dry or self-adhesive label provided with an electronic information display device of the aforementioned type. BRIEF DESCRIPTION OF THE DRAWINGS These and other objects, features, and advantages will be set forth in detail in the following description of non-limiting, non-limiting embodiments of the accompanying figures, in which: FIG. 1A is a schematic perspective view showing an exemplary embodiment of an electronic authentication device according to the present invention; Figure 1B illustrates a read operation of the authentication device of Figure 1A; FIGS. 2A and 2B are schematic top views showing an exemplary embodiment of a display area of an electronic authentication device 30 according to the present invention; FIGS. 3A and 3B are views, respectively in section and from above, illustrating in more detail one embodiment of a display area of an electronic authentication device according to the present invention; and B11016

FIGS. 4A and 4B are views, respectively in section and from above, illustrating another embodiment of a display area of an electronic authentication device according to the present invention. For the sake of clarity, the same elements have been designated by the same references in the various figures and, in addition, the various figures are not drawn to scale. DETAILED DESCRIPTION FIG. 1A is a perspective view schematically showing an embodiment of an electronic authentication device 10. In order to overcome the disadvantages of known electronic tags, the inventors propose an authentication device comprising a device. an electrochromic display (or display) 11 printed on a dielectric support 13 and a transponder connected to supply terminals of the display 11 to supply a supply voltage to the display 11 in the presence of a suitable electromagnetic wave. The dielectric support 13 is for example a support of the plastic or fabric type, or a cellulosic support such as paper or cardboard. In particular, it is possible to print the authentication device 10 directly on an object such as a packaging for packaging a product or a batch of products, on the product itself, or on a sensitive document (prescription secure, scratch game, etc.). Alternatively, it may be provided to print the device 10 on a label that will be subsequently associated with a product or batch of products. The label may be self-adhesive, or dry, that is to say not having an adhesive side.

According to a preferred embodiment, the transponder is specifically adapted to recover the energy of a wireless phone when the latter is approaching the authentication device. We can choose a transponder adapted to recover energy from other types of wireless devices (tablet, computer, etc.). For example, a B11016 is used

6 transponder chosen to operate in the presence of frequency waves between 800 MHz and 5 GHz. In this example, the transponder comprises an antenna 14 and a rectifying diode 15. It is possible to provide any other rectification device adapted instead of or in addition to the diode 15. The antenna 14 is preferably printed directly on the support 13 for example using conductive inks such as silver, nickel or copper inks, graphite carbon inks, or conductive polymer inks. The printing can be done by inkjet, flexography, or any other printing technique. Other non-printed embodiments of the antenna can also be envisaged.

The diode 15 may be printed directly on the dielectric support 13 using semiconductor inks. However, to obtain good rectification performance, especially at the frequencies mentioned above (of the order of 800 MHz to 5 Ghz), it will be preferred to use a conventional diode (or a converter or rectifier based on conventional diode), for example. for example a semiconductor diode such as a silicon diode or a germanium diode, carried on the dielectric support 13, for example by gluing. The diode may be embedded in the support 13 so that it does not form a protruding portion protruding from the authentication device 10. It may for example be used a diode whose substrate has been thinned. The display device 11 comprises a pattern 16 pre-printed in the manufacture of the authentication device, made of an electrochromic material, that is to say a material capable of reversibly changing color when applied to it. voltage. Examples of electrochromic display devices will be described in more detail below in connection with FIGS. 3A, 3B and 4A, 4B. The device 11 can be B11016

7 printed by flexography or any other suitable printing method. In the exemplary embodiment shown, in the non-powered state, that is to say in the absence of a suitable electromagnetic wave, the pattern 16 (in dotted lines in the figure) is invisible to the eye . To obtain this effect, it is possible to provide an upper layer of ink of the same color as the electrochromic material in the non-energized state, covering the entire surface of the authentication device 10 except for the pattern 16.

Figure 1B illustrates a read operation of the authentication device 10 of Figure 1A. A wireless device 17, for example a telephone, is approached by the device 10. The telephone 17 transmits an electromagnetic wave 18 at a normal operating frequency, for example between a few hundred MHz and a few GHz (for example from order of 900 MHz or of the order of 1.8 GHz for a conventional telephone). In the presence of the wave 18, the transponder provides a supply voltage causing a color change of the electrochromic material, which causes the pattern 16 (in black in the figure) to appear in contrast with the color of the device 10 (in white on the face). For example, the pattern 16 extends in a display area of a surface of the order of one square centimeter or greater, so as to be clearly visible to the naked eye. It should be noted that usual cordless telephones (or other wireless devices) generally transmit waves even in the absence of any communication initiated or received by the user. Thus, the mere fact of approaching the phone of the authentication device is sufficient to cause the display of the pattern 16. If necessary, the user can dial any number to ensure that the phone emits a wave to activate the authentication device. Alternatively, one can also provide to equip the phone or the wireless device with a program that allows the user to control the emission of the wave 18 at the desired time.

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The preprinted pattern 16 may be a logo, a mark, a message, or any other motive. In practice, the mere fact that a pattern appears in the presence of a wireless phone (or other device) is a strong indicator in favor of the authenticity of the object, because for most counterfeiters, such a device of authentication with an electrochromic display will be impossible or very difficult to manufacture. In addition, if the dielectric support 13 of the authentication device 10 is directly a packaging of a product or the support of a sensitive document, the device 10 can not be fraudulently diverted to be associated with a non-authentic object . In a particularly secure use, the pattern, for example, an optical reading code, can be photographed by the same telephone or other wireless device that provides power to the display device. The phone can then connect to a remote database to check the integrity of the code. It can also be provided that information about the product, contained in the remote database or in the optical reading code itself, for example provenance information, technical information, or advertising information, is displayed at the same time. phone screen. Of course this type of use requires the installation of a specific program in the phone. One advantage of the proposed electronic authentication device is that it can be read without specific equipment, since it is sufficient to approach a standard wireless phone to display the pre-printed pattern. In addition, even if a terminal dedicated to the emission of the wave 18 were provided, such a terminal would be extremely simplified compared to a terminal for reading a conventional electronic tag. Indeed, such a reading terminal would comprise an emitter of an electromagnetic wave, but no radio reception module, of B11016

9 processing of received data, or display would be necessary. In addition, the proposed authentication device is remotely readable (contactless), so that the user does not need to manipulate the marked object to verify its authenticity. FIGS. 2A and 2B are top views schematically representing an example of an electrochromic display 21 in which the shape of the preprinted pattern does not correspond to the shape of the electrochromic layer, as in the example described in relation to FIG. with Figures 1A and 1B, but in addition to a mask formed above this layer. Figure 2A shows the display 21 in the unpowered state. The electrochromic layer 22 occupies the whole of a display zone 23 (of square outline in this example). Electrodes 24a and 24b make it possible to apply a voltage to the electrochromic material. In this example, the electrodes 24a and 24b are respectively located at the top left and bottom right of the zone 23 (in the orientation of the figure). An opaque mask 25 is formed above the electrochromic layer 22, for example in an ink of the same color as the electrochromic material in the non-energized state. Openings of the mask 25 define the pattern 26 visible in the powered state. In this example, it is a two-dimensional optical reading code. Figure 2B shows the display 21 in the powered state, i.e. when a suitable voltage is applied between the electrodes 24a and 24b. Under the effect of this voltage, the electrochromic material changes color which causes the pattern 26 (in black in the figure) delimited by the mask 25 (in white in the figure) to appear in contrast with the color of the mask 25 (in FIG. white on the figure). When the power supply is interrupted, after a more or less short time due to the persistence of the electrochromic material, the layer 22 returns to its original color and the pattern 26 disappears.

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An advantage of this embodiment is that the electrochromic layer has a simple shape, for example square or rectangular, which facilitates the manufacture of the display. In particular, the arrangement of the contact electrodes is simplified. In addition, for a given authentication device format, the shape of the display area is always the same, the authentication device can be realized in large series, and therefore low cost. The mask 25, defining the pattern 26, can be realized only later, during a personalization step of the authentication device. The mask 25 can be made by standard printing means, for example by inkjet printing using a conventional graphic ink. This allows a great flexibility as to the choice of the pattern 26.

FIGS. 3A and 3B are views, respectively in section and from above, illustrating in more detail an exemplary embodiment of an electrochromic display 31. FIG. 3A is a sectional view of FIG. 3B along the plane A-A.

The display 31 comprises, on a dielectric support 32, a stack of five conductive layers, respectively 34 to 38, extending substantially over the entire surface of the display area 33. The layer 34, the closest to the support 32 , constitutes a lower electrode of the display 31.

The electrode 34 is for example a transparent conductive material such as ITO (of the English "Indium Tin Oxide" - indium-tin oxide) or an aluminum doped zinc oxide. A film 35 of electrochromic material coats the lower electrode 34. The electrochromic material may be tungsten oxide (WO3), a nickel or iridium oxide (NiOx, IrOx), Prussian blue, a polymer such as poly (3,4-ethylenedioxythiophene) (PEDOT) or polyaniline, or a derivative of bipyridine such as a viologen. An ionically conductive electrolyte 36, for example a hydrogen or lithium ion conductive electrolyte, coats the electrochromic film 35.

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The electrolyte 36 may be liquid, solid, or gel. A second electrochromic film 37, for example, but not necessarily, of the same material as the film 35, electrodes the electrolyte 36. An upper electrode 38, for example of the same material as the lower electrode 34, coats the film 37 A mask 39 is formed on the surface of the stack, for example in a conventional opaque graphic ink. The complement of the mask 39 corresponds to the pattern to be displayed. It may further provide a transparent top protective layer (not shown) covering the entire display 31, for example a protective varnish. When a suitable voltage is applied between the electrodes 34 and 38, a current flowing through the electrochromic films 35 and 37 and the electrolyte 36 flows. This results in a color change of the films 35 and 37 leading to making visible the pattern delimited by the mask 39. In this example, the electrodes 34 and 38 extend over the entire surface of the display area. This allows fast switching of the electrochromic material when a supply voltage is applied. However, in practice, it is sufficient for the electrodes 34 and 38 to be in contact with the electrochromic films 35 and 37 at two opposite points of the display area, for example at two diagonally opposite corners of the display area. for a current to flow through the electrochromic material (see for example Figures 2A and 2B). Any other suitable arrangement of the electrodes may be provided. Figures 4A and 4B are views, respectively in section and from above, illustrating another embodiment of an electrochromic display 41. Figure 4A is a sectional view of Figure 4B along the plane A-A. The display 41 comprises, on a dielectric support 42, a stack of three conductive layers, respectively 44, 45 and 46. The layer 44, the closest to the support 42, comprises two disjoint portions 44a and 44b constituting B11016

12 of the first and second electrodes of the device 41. The electrode 44a extends over the entire surface of a display area 43. The electrode 44b extends next to the electrode 44a, on a surface substantially identical. The layer 45, formed immediately above the electrode layer 44, is an electrochromic film comprising two disjoint parts 45a and 45b. The portion 45a of the film extends substantially above the electrode 44a, and the portion 45b of the film extends substantially above the electrode 44b. The layer 46 is an ionically conductive electrolyte substantially covering the entire surface of the display 41, and in particular the parts 45a and 45b and the gap that separates them. The electrolyte 46 thus provides electrical contact between the disjoint portions 45a and 45b of the electrochromic film.

A mask 49 covers the electrolyte 46, delimiting the pattern to be displayed inside the display zone 43. The electrochromic portion 45b, which is outside the display zone 43, is entirely covered by the mask 49 so that it is not visible in the powered state.

When a suitable voltage is applied between the electrodes 44a and 44b, a current flowing through the portions 45a and 45b of the electrochromic film and the electrolyte 46 is circulated. This results in a color change of the electrochromic material, leading to making visible the pattern in contrast to the color of the mask 49. An advantage of the display 41 with respect to the display 31 described in connection with Figures 3A and 3B is that it comprises only three conductive levels, against five for the 31. This makes its manufacture easier. In contrast, for a given display area format, the authentication device occupies a larger area, to support the non-visible portion 45b of the electrochromic material.

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Particular embodiments of the present invention have been described. Various variations and modifications will be apparent to those skilled in the art. In particular, the electrochromic displays described in connection with FIGS. 3A to 4B have been mentioned solely by way of example. Those skilled in the art will know how to use any other type of electrochromic display device printable on a dielectric support. In addition, those skilled in the art will be able to use any other type of transponder than that described in connection with FIGS. 1A and 1B. In addition, the invention is not limited to the operating frequencies mentioned above by way of example. Those skilled in the art will be able to provide an authentication device capable of being activated by other frequency ranges than the frequencies of the cordless telephones. Furthermore, the present invention has been described in connection with an example of use for authentication purposes for protection against fraudulent imitation of sensitive objects (products or documents). The proposed electronic device may however have other uses, for example for advertising purposes or traceability of objects. Thus, more generally, the proposed device is a device for displaying information, this information may be authentication information or information of another type.

Claims (13)

REVENDICATIONS1. An electronic information display device (10) comprising: an electrochromic display (11; 21; 31; 41) printed on a dielectric support (13; 32; 42); and a transponder (14, 15) connected to supply terminals of the display (11), adapted to supply a supply voltage to the display (11) in the presence of a suitable electromagnetic wave (18). 2. Device according to claim 1, wherein the transponder (14, 15) is chosen to operate when said wave (18) has a frequency between 800 MHz and 5 GHz. 3. Device according to claim 1 or 2, wherein the transponder (14, 15) is chosen to operate when said wave (18) corresponds to a wave transmitted by a cordless telephone (17) positioned near said device. 4. Device according to any one of claims 1 to 3, wherein the display (11; 21; 31; 41) comprises a pattern (16; 26) whose color changes when the display receives said supply voltage. . 5. Device according to claim 4, wherein the shape of said pattern (16; 26) is bonded to the shape of a layer of an electrochromic material (22; 35, 37; 45a, 45b), this layer having a first color in the non-powered state, and a second color when said supply voltage is applied. The device of claim 5, wherein the shape of said pattern (26) is further mask-shaped (25; 39; 49) formed above the electrochromic layer (22; 35,37; 45a). , 45b). The device of claim 6, wherein said mask (25; 39; 49) is printed with an opaque ink of said first color. 8. Device according to any one of claims 1 to 7, wherein the transponder comprises an antenna (14) and a rectifying diode (15), said antenna being printed on the dielectric support (13) using a conductive ink. 9. Device according to claim 8, wherein the rectifying diode (15) is a semiconductor diode carried on the dielectric support (13). 10. Device according to any one of claims 1 to 9, wherein the dielectric support (13) is a cellulosic carrier such as paper or cardboard. 10 11. Device according to any one of claims 1 to 10, wherein the dielectric support (13) is a part of a packaging package. Packaging package with an electronic information display device (10) according to any one of claims 1 to 11. A dry or self-adhesive label provided with an electronic information display device (10) according to any one of claims 1 to 11.