Microcircuit board including an insert with an LED between reflective films

Abstract

Microcircuit board comprising an insert with an LED between reflective films. Microcircuit board comprising: a first support layer (101), a second support layer (102), an insert (103) comprising at least one light-emitting diode (LED) (106), the insert being arranged between the first support layer and the second support layer, wherein a first reflective film (109), for example metallic, is arranged between the first support layer and the insert, and a second reflective film (110), for example metallic, is arranged between the second support layer and the insert, the first reflective film and the second reflective film extending opposite each other from the level of said at least one LED to at least one edge of the microcircuit board. Figure for the abstract: Fig. 2.

Description

Title of the invention: Microcircuit board comprising an insert with an LED between reflective films technical field

[0001] The invention relates to the field of microcircuit boards, and in particular contactless microcircuit boards equipped with an antenna. Previous technique

[0002] Microcircuit boards generally comprise a microcircuit connected to an antenna, which can be arranged on an insert, usually referred to by the English term "inlay". The antenna can be used for communication with a terminal, for example by implementing communications according to ISO 14443 in all its versions, and in particular the 2018 version.

[0003] A microcircuit board insert is usually arranged between two support layers ("core layers" in English), which are for example polymer layers, which protect the antenna, the microcircuit, and which provide faces on which information can be printed.

[0004] From the prior art, we know of EP 2426627, which describes microcircuit card modules equipped with light sources (typically light-emitting diodes (LEDs)). In this document, the light sources are powered using their own antenna, which reacts to the electromagnetic field of the terminals with which the microcircuit cards can communicate (via another antenna). The integration of light sources improves the visual effect of the cards and can be useful for signaling to a user that a transaction has been validated or that the card is within the electromagnetic field range of a terminal.

[0005] That being said, in the cards of this prior document, light effects are produced for example by transmission through the support layers, which a user may perceive as a light halo (which for example indicates that the card is within range of a contactless terminal), and which is not always satisfactory in terms of visibility (for example if the card is stored in a wallet, or even stacked with other cards).

[0006] In addition, lighting such as that produced by the cards in this document may affect the readability of the information on the faces of the microcircuit board.

[0007] There is a need for alternative lighting methods for microcircuit boards, in which the lighting is more easily detectable by a user. Description of the invention

[0008] To this end, the present invention relates to a microcircuit board comprising:

[0009] a first support layer,

[0010] a second support layer,

[0011] an insert comprising at least one light-emitting diode (LED) (for example, the insert may comprise one or more LEDs), the insert being arranged between the first support layer and the second support layer,

[0012] in which a first reflective film, for example metallic, is arranged between the first support layer and the insert, and a second reflective film, for example metallic, is arranged between the second support layer and the insert,

[0013] the first reflective film and the second reflective film, extending opposite each other from the level of said at least one LED (which emits radiation in the visible range) to at least one edge of the microcircuit board.

[0014] Thus, the invention proposes to place at least one LED in the middle of a stack comprising the LED and the two reflective films, so that the light rays which are emitted by the LED (or at least a portion of these rays) will be guided by the two reflective films at least to at least the edge of the card reached by the two films.

[0015] In other words, a light guide is formed to guide the light towards at least one edge of the card. This allows us to perceive radiation emanating from the edge of the card, sometimes called the card's edge.

[0016] It therefore appears that if the edge is an accessible edge (which protrudes) when the card is stored in a wallet, the light radiation can be perceived (for example if the card is within the range of an electromagnetic field received by an antenna which powers the LED).

[0017] LEDs that can be used in microcircuit boards are generally thin and typically have a narrow front emission cone that illuminates what is directly facing the LED. The use of reflective films overcomes this drawback, allowing for edge-to-edge illumination. LEDs with other emission cones can also be used, for example, side-emitting LEDs (emitting light around the LED).

[0018] It should be noted that by reflective, we mean reflective for at least the emission spectrum of said at least one LED in the visible range. A person skilled in the art will know how to choose the materials for the two films and their thickness to limit measurable transmission through these films.

[0019] Also, by extending, we mean extending so as to provide a straight path between said at least one LED and the edge.

[0020] As indicated above, reflective films can be metallic films. By metallic, it is understood that they comprise metal, for example a or several layers of metal (for example aluminium), or even metal particles (for example silver).

[0021] The invention is nevertheless not limited to metallic films, other reflective films can be used, for example non-metallic multilayer films.

[0022] It can be noted that the card being a microcircuit card, it includes a microcircuit which can be arranged directly on the insert, or which can be arranged in a module itself assembled with the insert.

[0023] Assembling the microcircuit directly onto the insert is suitable for microcircuit boards that operate only in contactless mode. The microcircuit can be connected to an antenna that is on the insert.

[0024] The use of a microcircuit arranged in a module is suitable for dual-interface cards (contact and contactless), with microcircuit modules generally including reader connection areas in contact mode. The module, and therefore the microcircuit, is generally connected to an antenna on the insert to enable contactless mode for dual-interface cards.

[0025] According to a particular embodiment, the first reflective film and the second reflective film extend opposite each other across the entire plane of the card (optionally with windows / openings opposite antenna coils arranged on the insert).

[0026] In this particular embodiment, the two films are continuous between the four edges of the microcircuit board, which is substantially rectangular. The light emitted by the LED is thus transmitted to all edges or slices, without any portion of the radiation being absorbed, for example, by the support layers.

[0027] According to a particular embodiment, the first reflective film and the second reflective film are assembled by lamination between the insert and respectively the first support layer and the second support layer.

[0028] It can be noted that a film obtained by lamination has particular technical characteristics in terms of composition; for example, if it is a metallic layer, it may include layers of metal such as those obtained by processes such as spraying onto a substrate layer. In particular, these layers do not contain particles embedded in a matrix of binders or resin.

[0029] According to a particular embodiment, the first reflective film and the second reflective film are films obtained by printing.

[0030] For example, a printed layer may include not only metallic pigments (in the case of a metallic film), but also binders (for example resins) or solvents (which is not the case for a layer assembled by lamination).

[0031] According to a particular embodiment, the reflective film arranged on the side of the insert that supports said at least one LED has a raised portion positioned opposite said at least one LED.

[0032] This portion, which is reflective and raised, can direct the light rays emitted by the LED so that they are deflected towards the edges of the microcircuit board. This further optimizes the transmission of light to the edges of the microcircuit board.

[0033] It can be noted that if the microcircuit board has several LEDs, a single raised portion can be used in relation to the several LEDs, or several raised portions for each LED.

[0034] According to a particular embodiment, said raised portion has a convex shape when viewed from said at least one LED.

[0035] This convex shape (typically a bump) is well suited to deflect light rays towards the edges of the card.

[0036] According to a particular embodiment, the insert comprises a transparent insert support layer.

[0037] This insert support layer can be the main layer of the insert, i.e., the sole support of the insert, which supports the LED, the microcircuit, etc. By being transparent (for at least the emission spectrum of the LED), the transmission of light is increased.

[0038] The invention is nevertheless not limited to transparent insert support layers and also applies to other layers.

[0039] For example, according to a particular embodiment, the insert comprises a transparent insert support layer comprising non-transparent particles.

[0040] This particular embodiment allows for the diffusion of light rays between the two reflective films, thereby homogenizing the radiation at the edges of the microcircuit board. Preferably, the non-transparent particles are present at a very low particle concentration, for example, on the order of 1 to 10%.

[0041] According to a particular embodiment, the card comprises:

[0042] between the insert and the first reflective film, a first transparent layer of Thickness compensation, and,

[0043] between the insert and the second reflective film, a second transparent thickness compensation layer.

[0044] This embodiment is advantageous in that it prevents direct contact between said at least one LED and the reflective metallic films, thereby facilitating light transmission to the edges. Also, this embodiment helps to limit the raised areas resulting from the presence of the LEDs and the microcircuit (if it is on the insert), and antennas, which could be seen from outside the card. This embodiment also improves the robustness of the laminations used during the card's manufacture.

[0045] According to a particular embodiment, the insert includes a main antenna configured to electrically supply the microcircuit of the microcircuit board, and a secondary antenna configured to electrically supply said at least one LED.

[0046] These two antennas are distinct.

[0047] The secondary antenna can power said at least one LED when it is present within the range of the electromagnetic field emitted by a terminal that can communicate with the microcircuit by means of the main antenna.

[0048] It can be noted that in the embodiment where the films extend facing each other across the entire plane of the card, the films may have windows opposite the coils of the antennas so as not to affect their operation.

[0049] The invention also proposes a method for manufacturing a microcircuit board in which the following are assembled:

[0050] a first support layer,

[0051] a second support layer,

[0052] an insert comprising at least one light-emitting diode (LED) and arranged between the first support layer and the second support layer,

[0053] in which a first reflective film, for example metallic, is assembled between the first support layer and the insert, and a second reflective film, for example metallic, is assembled between the second support layer and the insert,

[0054] the first reflective film and the second reflective film extending opposite each other from the level of said at least one LED to at least one edge of the microcircuit board.

[0055] This process can be adapted for the manufacture of microcircuit boards according to all embodiments of the microcircuit board as described above.

[0056] According to a particular embodiment, the first reflective film and the second reflective film are assembled by lamination between the insert and respectively the first support layer and the second support layer.

[0057] According to a particular embodiment, the first reflective film and the second reflective film are printed. Brief description of the drawings

[0058] Other features and advantages of the present invention will become apparent from the description below, with reference to the accompanying drawings which illustrate non-limiting examples of embodiments. In the figures:

[0059] [Fig. 1] Fig. 1 is a cross-sectional view of a microcircuit board according to an example,

[0060] [Fig.2] Fig.2 is a cross-sectional view of the microcircuit board of Fig.1 when The LED is working.

[0061] [Fig.3] Fig.3 is a cross-sectional view of a microcircuit board according to another example,

[0062] [Fig.4] Fig.4 is a cross-sectional view of a microcircuit board according to yet another another example,

[0063] [Fig. 5] Fig. 5 shows, from the front, the arrangement of the LED, the microcircuit, and the antennas, and

[0064] [Fig.6] The [Fig.6] is a cross-sectional view of a microcircuit board according to another example. Description of the implementation methods

[0065] We will now describe microcircuit boards comprising LEDs but which are capable of producing visible light radiation on one edge of the board.

[0066] In the examples that will be described, all the edges of the card are illuminated. However, the invention is not limited to this aspect and also covers cases where an edge can be illuminated by a portion of the light emitted by the LED (the other portion being absorbed by elements of the card or transmitted by other edges).

[0067] The microcircuit boards described here are microcircuit boards that can communicate with terminals by contactless communication, for example according to ISO 14443 in all its versions and in particular that of 2018. Boards of this type will be described with reference to figures 1 to 5.

[0068] The microcircuit boards described herein may also be microcircuit boards conforming to ISO 7816 (in all its versions, and in particular the 2011 version). This standard defines dimensions for microcircuit boards and provides that contact communication is possible. For example, the microcircuit boards described herein may be dual-interface boards: contact and contactless. A board of this type will be described with reference to [Fig. 6].

[0069] Figure 1 shows a cross-sectional view of a microcircuit board 100. This figure shows that the board 100 comprises a first support layer 101 and a second support layer 102 (the "core layer"). These support layers are, for example, polymer layers, such as opaque polycarbonate layers, for example white (the polymer may contain particles that give it this opaque white appearance), or also polyvinyl chloride (PVC) or glycol-based polyethylene terephthalate (PETg). They can have a thickness on the order of 100 to 250 µm.

[0070] Although not shown for simplicity, above the first support layer 101 (the top face of the card 100) and below the second support layer 102 (the bottom face of the card 100), printable overlay layers can be assembled, on which information specific to each microcircuit card can be printed (typically information about the user of the microcircuit card, which can be a person's card).

[0071] Between the two support layers 101 and 102, an insert 103 (or "inlay") is arranged, which supports various components of the microcircuit board 100. The insert 103 comprises an insert support layer 104, which is here a transparent polymer layer (for example, polyester with a thickness of approximately 10 to 20 µm), with a top face F. The insert support layer 104 extends to all edges of the board 100.

[0072] On the upper face F, a microcircuit 105 and an LED 106 are assembled. The microcircuit 105 can be configured to communicate contactlessly by means of an antenna 107, the turns of which are visible in the figure, for example, and as indicated above according to ISO 14443. In fact, this microcircuit can be configured to perform transactions, for example, authentication or banking transactions, using this standard. In an alternative embodiment described below with reference to [Fig. 6], the microcircuit 105 is in a module and connected to a set of contacts arranged on the upper face of the first support layer 101, to perform contact communications, for example, according to ISO 7816 mentioned above.

[0073] The LED 106 is electrically connected to an antenna 108 (optionally through an LED control circuit) which, when within range of the electromagnetic field emitted by a terminal capable of communicating with the microcircuit board in a contactless communication mode, will deliver an electric current to the LED 106 which will be able to emit light.

[0074] LEDs, and more specifically thin LEDs suitable for integration into a microcircuit board, generally have a front emission cone, which illuminates the surface opposite the LED substrate (side-emitting LEDs can also be used). Here, LED 106 is on face F and illuminates above it in the figure. To prevent light transmission through the first substrate layer 101, a first reflective metallic film 109 is arranged between the insert 103 and the first substrate layer 101. The rays emitted by LED 106 will be reflected by this film. To prevent reflected light transmission through the second substrate layer 102, a second reflective metallic film 110 is arranged between the insert 103 and the second substrate layer 102. The operation of the two films... Reflective tallics will be visible on [Fig.2].

[0075] The two reflective metallic films may be films comprising aluminum, for example having a metal thickness on the order of several Angstroms. In this case, they may be laminated (for example, hot-laminated at 140°C) with the insert and the two support layers.

[0076] Alternatively, the two reflective metallic films may be films obtained by printing with a metallic ink. For example, a metallic ink containing silver particles may be used, with a printed thickness of between 5 and 15 µm. As an example, inks such as those marketed by the French company VFP Ink Technologies under the references AC301, AC302, AC303, or AC9003 may be used.

[0077] Printing can be done directly on the insert (on the side of face F and possibly on the other side).

[0078] Non-metallic films may also be used, for example multi-layer reflective films.

[0079] It can be noted that windows (not shown in [Fig. 1]) can be formed in films 109 and 110 opposite antennas 107 and 108, so as not to affect their operation.

[0080] The card in [Fig.1] has two transparent thickness compensation layers, for example polyester layers, which can compensate for the thickness of the microcircuit or the LED, and which will allow the light rays to propagate between the insert and the reflective metallic films.

[0081] More specifically, a first transparent thickness compensation layer 111 is assembled here between the insert 103 and the first film 109, and a second transparent thickness compensation layer 112 is assembled between the insert 103 and the second film 110.

[0082] It can be noted that adhesives can be used between the different layers mentioned above.

[0083] Subsequently, when the same elements are present and already described, the same references will be used on this figure as on the previous ones.

[0084] Figure 2 shows the card 100 described with reference to Figure 1 in an operating mode. Here, the card 100 is within the electromagnetic field range of a terminal (not shown), so that the antenna 108 carries an electric current which supplies electrical energy to the LED 106.

[0085] In this figure, light rays RY are also shown being guided from LED 106 to the two edges visible in the figure. Since the reflective metallic films 109 and 110 extend over the entire surface of the board, the light is guided not only to these two edges, but also to the other two edges which do not are not visible in the figure.

[0086] Figure 3 shows a card 100' according to another example, in which the first metallic film, which is arranged on the side of the insert that supports the LED 106, has a raised portion 115 positioned opposite said LED. The raised portion 115 has a convex shape when viewed from the LED. For example, the raised portion 115 may have a domed shape, a cone shape, or a pyramid shape. Other shapes are also conceivable for the raised portion, preferably shapes that are configured to deflect at least a portion of the radiation emitted by the LED towards at least one edge.

[0087] With the raised portion 115, the light rays emitted by the LED are deflected further towards the edges, and a radiation RY' is obtained which can be more intense than the radiation RY described with reference to [Fig.2].

[0088] Fig. 4 shows a 100” card according to yet another example, in which the insert support layer 104' differs from the support layer 104 described with reference to Figures 1 to 3 in that it comprises non-transparent particles 116.

[0089] For example, these particles may be reflective particles, and they may be dispersed in the material of the insert support layer 104'.

[0090] These particles make it possible to obtain a diffusive effect, which will homogenize the RY' radiation observable at the edges of the map, compared to the RY and RY' radiations described above which may exhibit irregularities in light radiation along the edges of the maps.

[0091] Fig. 5 is a front view of the card 100, which shows the arrangement of the microcircuit 105, the LED 106, and the antennas 107 and 108.

[0092] Here, the turns of antenna 108 are completely surrounded by the turns of antenna 107. Other arrangements are possible. For example, the turns of antenna 108 can be placed between turns of antenna 107, or the turns of antenna 108 can be placed next to the turns of antenna 107. Preferably, the turns of antenna 107 surround a larger surface area than that of antenna 108.

[0093] In [Fig.5], we also see that the card includes a control circuit 120 for the LED 106. The control circuit 120 is powered by the antenna 108 and can control the operation of the LED 106, for example to produce a particular radiation, or control an operation which only takes place when a condition is met (for example a transaction validated by the microcircuit 105).

[0094] Figure 6 shows, in cross-section, a 100" microcircuit board that can communicate via two interfaces (when the same elements are present, the same reference numerals are used in this figure as in the previous ones). In the same way as for the boards described above, the board can communicate contactlessly according to the ISO standard.

[0095]

[0096]

[0097]

[0098]

[0099]

[0100] 14443. Its microcircuit connected to the antenna 107 is not, however, directly on the insert but integrated into a module 130, which is connected to the antenna by antenna contacts 131. The module 130 is arranged in a window of the support layer 101 and extends between the insert and the top face shown in the figure. The module has one face that is flush with the top face of the support layer 101, and this face has contacts 132 connected to the microcircuit that can be used for communication according to ISO 7816. In this embodiment, the edges of the card are also illuminated. It has been observed that for a card according to the prior art without reflective metallic films, the following values ​​of brightness corrected with respect to limited stray light (on the order of 0.04 Lux) are obtained: Terminal field of view (A / m) Corrected brightness (Lux) 1.5 0.16 2.5 0.28 4.5 0.51 5.5 0.62 All measurements in this description are taken at the edges of the maps. For a card such as card 100 with printed reflective metallic films, we obtain: Terminal field of view (A / m) Corrected brightness (Lux) 1.5 0.22 2.5 0.38 4.5 0.77 5.5 0.91 And, for a card such as card 100 with laminated reflective metallic films, we obtain: Terminal field of view (A / m) Corrected brightness (Lux) 1.5 0.20 2.5 0.41 4.5 0.80 5.5 1.06 It can be noted that reflective metallic films have an increased efficiency with the intensity of the terminal's field, and can increase brightness by 71% compared to a card without these films.

[0101] The invention therefore makes it possible to concentrate the light radiation of the LEDs included in the microcircuit boards towards the edges.

[0102] In the three tables presented above, diodes with a front emission cone have been used.

[0103] Side-emitting diodes can also be used, the use of which is also improved in terms of transmission to the edges by the use of reflective films: Terminal field of view (A / m) Corrected brightness, absence of reflective films (Lux) Corrected brightness, presence of reflective films (Lux) 1.5 2.96 5.06 3.5 7.14 15.42 5.5 6.35 22.80

[0104] It can be noted that an increase in brightness at the edges of the order of 200% is obtained.

[0105] A person skilled in the art will understand that the embodiments and variants described above are merely non-limiting examples of implementation of the invention. In particular, a person skilled in the art may consider any adaptation or combination of the embodiments and variants described above in order to meet a very specific need in accordance with the claims set forth below.

Claims

Claims

1. Microcircuit card comprising: a first support layer (101), a second support layer (102), an insert (103) comprising at least one light-emitting diode LED (106), the insert being arranged between the first support layer and the second support layer, wherein a first reflective film (109), for example metallic, is arranged between the first support layer and the insert, and a second reflective film (110), for example metallic, is arranged between the second support layer and the insert, the first reflective film and the second reflective film extending facing each other from the level of said at least one LED to at least one edge of the microcircuit card, wherein the first reflective film (109) and the second reflective film (110) extend facing each other in the entire plane of the card.

2. A card according to claim 1, wherein the first reflective film (109) and the second reflective film (110) are assembled by lamination between the insert and respectively the first support layer and the second support layer.

3. The card of claim 1, wherein the first reflective film (109) and the second reflective film (110) are films obtained by printing.

4. Card according to any one of claims 1 to 3, wherein the reflective film (109) arranged on the side of the insert which supports said at least one LED has a raised portion (115) positioned opposite said at least one LED.

5. A card according to claim 4, wherein said raised portion (115) has a convex shape when viewed from said at least one LED.

6. A card according to any one of claims 1 to 5, wherein the insert (103) comprises a transparent insert support layer (104).

7. A card according to any one of claims 1 to 5, wherein the insert comprises a transparent insert support layer (104') comprising non-transparent particles (116).

8. A card according to any one of claims 1 to 7, comprising: between the insert and the first reflective film, a first transparent thickness compensation layer (111), and, between the insert and the second reflective film, a second transparent thickness compensation layer (112).

9. Card according to any one of claims 1 to 8, in which the insert comprises a main antenna configured to electrically power the microcircuit of the microcircuit card, and a secondary antenna configured to electrically power said at least one LED.

10. Method for manufacturing a microcircuit card in which: a first support layer (101), a second support layer (102), an insert (103) comprising at least one light-emitting diode LED (106) and arranged between the first support layer and the second support layer, in which a first reflective film (109), for example metallic, is assembled between the first support layer and the insert, and a second reflective film (110), for example metallic, is assembled between the second support layer and the insert, the first reflective film and the second reflective film extending facing each other from the level of said at least one LED to at least one edge of the microcircuit card, in which the first reflective film (109) and the second reflective film (110) extend facing each other in the entire plane of the card.

11. The method of claim 10, wherein the first reflective film (109) and the second reflective film (110) are assembled by lamination between the insert and the first support layer and the second support layer respectively.

12. The method of claim 11, wherein the first reflective film (109) and the second reflective film (110) are printed.

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