Technical field of the invention

The present invention relates to the field of tobacco, in particular to reconstituted tobacco as well as aerosol-generating articles. The present invention further relates to smoking devices, especially to an electrically heated e-liquid system or an electrically heated aerosol-generating system.

Background of the invention

Electronic cigarettes based on aerosol-generating consumable articles have gained popularity in the recent years. There are mainly two types: liquid vaporizers and heated tobacco inhaler devices. Heated tobacco inhaler devices are referred to as “heat-not-burn” systems (HNB). They provide a more authentic tobacco flavour compared to electronic cigarettes, which deliver an inhalable aerosol from heating of a liquid charge comprising aerosol formers, flavorants, and often nicotine. The HNB system’s working principle is to heat a tobacco material comprising an aerosol-forming substance (such as glycerine and/or propylene glycol) which vaporises during heating and creates a vapour that extracts nicotine and flavour components from the tobacco material. The tobacco substance is heated to between 200 and 350°C, which is below the normal burning temperatures of a conventional cigarette. The inhaler device is typically a hand-held heater, which is configured to receive rod-shaped consumable articles.

Illicit trade of aerosol-generating articles, be it e-liquids or HNB articles, is a problem, as counterfeit articles in particular may be of inferior quality, may not guarantee a controlled delivery amount of aerosol or may not be suited to a specifically dedicated aerosol generating system. In order to identify if an aerosol generating consumable article is an authentic one, a code or equivalent marking containing information about the article may be arranged onto an outer surface of the article, for it to be detected in use or prior use with a certain device. This allows to check for authenticity of the consumable article and in case of negative check, to provide an appropriate control, such as to power off or correctly adjust the heating system with which it is used.

Moreover, there may be also a need for distinguishing a consumable article from another article for the purpose of adapting the aerosol generating conditions. For example, certain consumable articles within a range of articles may contain different constituents (e.g. different tobacco blends, forming agents, nicotine levels, etc.) which so require different parameter settings for the device to optimize the consumer experience.

To provide accurate authentication of a code on a consumable article such as an HNB article, the recognition probability should be very high so that suitable articles will not be rejected. However, existing indicia are limited by the low density of information that may be contained in them, and most known indicia rely on classic codes such as 1 -Dimensional or 2-Dimensional barcodes that may be easily be copied without using specific optical instruments, for example by simply visualizing the code by the human eye.

Various attempts at providing authenticatable aerosol-generating articles have been proposed in the prior art already.

WO201 9185747 discloses an e-cigarette comprising an article that includes an indicia, arranged on a surface of the article, and which is indicative of an encoded parameter associated with the article. The e-cigarette also comprises a sensor arrangement to sense the indicium to identify or recognize the article. The fact that an indicium is applied on articles constitutes an additional step, makes the production process complicated and there is also an issue on the stability of inks in a harsh environment such as the one near to a heater as required in an aerosol-generating device.

US20190008206A1 discloses a smoking article comprising an indicium printed on the outer wrapper paper of the smoking article and represents a type of smoking article and may be in the form of pattern or one/two-dimensional barcode. The indicium includes different grey levels that can be generated by printing in dots which have smaller size. Such indicium is easily detectable and reproducible and may contain only a small density of information, or to be provided with an unacceptably large size. The system described in US20190008206 A1 relies on printed indicia which optical properties have to match the LEDs used in the sensor module, such as having specific infrared absorption bands. The fact that an indicium has to be printed on an articles as an additional step, makes the production process complicated and there are also problems related to the stability of inks in a harsh environment such as the one near to a heater as required in an aerosol-generating device. US2015128969 discusses a mouthpiece embodied as a cartridge of a smoking article of an aerosol-generating device is wrapped using a double layer tipping wrap. The outer layer of the double-layer tipping wrap includes indicia that identify properties of the mouthpiece and a smoking article. The outer layer can be in the form of an adhesive label. The outer layer of the double-layer tipping wrap includes indicia that identify properties of the mouthpiece and a smoking article. The indicia provide information such as flavor(s) and product source identification. The fact that an indicium has applied or be printed on a layer of the article, constitutes an additional step, and makes the production process complicated and more expensive. The applied indicium may also be easily identified and reproduced.

There is thus a need for an improved technique to allow authentication of aerosol-generating articles such as HNB, vaping and smoking articles. Furthermore, there is a need for identification methods that are much simpler than all the indicia marking of prior art. There is also a need for an identification solution that is more robust and less subject to alteration or damage such as due to heat.

Summary of the invention

The inventors of the present invention have found solutions to the above-discussed problems by providing an authentication method and system of identification that does not require the use of added or incorporated indicia onto or into a consumable product. The invention relies on inherent geometrical and physical properties of layers or structures that can be repetitive and systematic in usual fabrication processes of aerosol-generating consumables. The proposed solution is based on the detection and/or imaging and the identification of the arrangement and/or the physical and/or the dimensional properties of layers or structures or elements. This allows to provide an inherent available reference by which a consumable may be recognized at its consumption. Furthermore, the method allows to provide a cheap and extremely secure individual recognition of aerosol-generating consumables. Preferably, layers such as a seam or glue layer or bond are used to identify an article.

In a first aspect the invention is related to a method of identifying a consumable in an aerosol generating device comprising: - providing a consumable comprising identification information in the consumable identifiable by identification means of the device,

- identifying the consumable based on the identification information by the identification means, wherein the identification information is encoded by at least one variable characteristic identifiable by identification means of the device the characteristic being representative of different arrangements of at least one layer in the aerosol-generating consumable article; the layer being chosen among: a glue layer, a seam, a bond, or a separation layer, the variable characteristic being chosen amongst: - the presence and/or shape of said at least one layer, a thickness, a width, a cross section, a length of said at least one layer, surface properties of said at least one layer, the optical and/or electrical properties of said at least one layer, and combinations thereof. Identification information is preferably information that is produced by the characteristics of the layers obtained during or as a result of the manufacturing process of the consumables. For example, process parameters during the manufacturing of the consumable article may be adapted or set up to obtain repeatable defects or signature characteristics in the layer. The advantage is to reduce the manufacturing complexity for creating an authentication indicium for the article.

In an embodiment, the characteristic is an adhesive seam. The advantage to use it as a characteristic for authentication of the article, is that the adhesive has properties is that they are inherent to the production process of the consumable and therefore unique and very difficult to replicate. Indeed, articles are typically manufactured in a back-to-back configuration by rolling a wrapper sheet around a rod formed of first and second inner tubular elements arranged to mouthpiece filters. Adhesive seams do not have to be continuous seams Adhesive seams or glue layers or plurality of attachment or glue dots may present defects such as variations of their diameter, their shapes in any cross-section, or may present rugosities, or surface and/or volume contaminations such as the presence of particles. The characteristic may be coming as a defect or signature of the manufacturing process and may present a unique identification indicium of the machine and process used to fabricate consumables and provide as such an effective way to identify the articles. The information on said characteristic may be stored in a memory of the device so that the device may perform a recognition detection of an article at its consumption. Identification information as described in the invention may also be stored in a data chip integrated into or onto a package of the articles.

In an embodiment, the variable characteristic is an identifiable shape of the cutting edge of said at least one layer. The shape may for instance be toothed, notched, undulated, or designed with a non-nil angle relative to the extension direction of the layer. The cutting edge may have a variation of curvature and/or inclination relative to the longitudinal axis of the consumable article. The pattern may be varied in amplitude, period, width, and combinations thereof. The shape of the cutting edge may be produced in a repetitive way during the manufacturing process. The shape of the cutting edge may be varied depending on the type of article to be identified, e.g., to distinguish between different tobacco blends. For example, the optical properties of the cutting edge can be identified under light by an optical detector, such as photodiodes, of the aerosol generating device.

In embodiments the variable characteristic is the rugosity of said at least one layer.

The variable characteristic may also be, at least, a spectral characteristic of at least a portion of said at least one layer.

In advantageous embodiments the variable characteristic is the non uniformity of at least one of: a thickness, a width, a cross section of said at least one layer.

In variants, characteristics may be combined, such as the combination of a variable thickness, width, length, surface roughness or cross-section shape of said at least one layer. Combining the information on different characteristics allows to improve the identification reliability of a consumable article. In an embodiment the characteristic is the electrical property of a conductive thread arranged in or on said at least one layer. Using a conductive thread allows to provide a further security level as it makes the articles even more complicated to counterfeit. Furthermore, the imaging correlation process as described here may be combined by an additional detection that relates to an electrical detection of the presence of a conductive thread.

In an embodiment, the characteristic is the optical property of an insert arranged in or on said at least one layer. Inserts may be present in an article, for example rigidifying layers as further described.

In advantageous embodiments, the characteristic may be the variation or distribution of electrical and/or optical properties of a layer along a length and/or a width of said at least one layer. In an example the characteristic may be a specific difference in conductivity in the length of a glue layer comprising electrically conductive particles. In an embodiment said at least one layer is a plurality of glue bands, preferably an array of glue bands. The glue bands may be arranged in an aligned relationship such as in the axial direction of the aerosol generating article. The alignment of the glue bands may be used as a variable characteristic. In an alternative, the glue bands may be arranged in parallel. The glue bands may pertain to different components (e.g. tipping paper, plug wrap, paper tube, etc.) of the articles or be arranged at different levels of thickness of a same component. For example, a pair of parallel glue bands of different components may be arranged at a repeatable circumferential distance. The distance may be varied depending on the type of article to be identified and may serve for distinguishing the types of articles from others.

In a variant, at least one band may comprise a plurality of glue dots or glue lines. A particular arrangement of the glue layers or bond or seam are produced during manufacturing process of the consumables, in particular HNB aerosol generating articles, can so serve as such as identification indicium of the article without requiring additional elements.

In an embodiment, the at least one layer has a non-uniform geometry in its length and/or its width. Varying the geometries of the layer can be implemented in the manufacturing process without much complexity. The variable geometry may thus be used to identify the article such as for verifying if it is genuine or distinguishing articles from other articles for setting up device parameters. In particular, the non-uniform geometry can be a variation of thickness and/or form of the layer.

In a second aspect, the invention relates also to an aerosol-generating system comprising an aerosol-generating device and an aerosol-generating consumable article inserted, at least partially, in said aerosol-generating device. The consumable comprises: an aerosol-producing substrate, and a wrapper and/or rigidifying component, - and identification information encoded for identifying the consumable in said aerosol-generating device wherein the identification information is encoded by at least one variable characteristic identifiable by identification means of the aerosol- generating device.

The characteristic is representative of different arrangements of at least one layer in the aerosol-generating consumable article.

The at least one layer is chosen among: a glue layer, a seam, a bond or a separation layer, and the variable characteristic is chosen amongst: - the presence and/or shape of said at least one layer, a thickness, a width, a cross section, a length of said at least one layer, surface properties of said at least one layer,

- the optical and/or electrical properties of said at least one layer, and combinations thereof.

In embodiments, the at least one layer may be an at least partially electrically conductive layer.

In an embodiment said at least one layer is an adhesion or a joining layer that is made, at least partially, of an intrinsically conducting polymer, known as ICP’s. The advantage of such an ICP layer is that is electrically conducting without comprising metallic particles or metallic compounds.

In an embodiment, the consumable article comprises an aerosol- producing substrate; and a wrapper and/or a rigidifying component and the characteristic is an adhesive seam of the paper wrapper and/or rigidifying component. In a preferred mode, the rigidifying component is an inner tubular member covered by a wrapper. The inner tubular member may be a paper or polymer tube of thickness greater than the thickness of the wrapper. The tubular member may be positioned between an aerosol generating portion and a filter portion of the consumable article. The tubular member may have the function of cooling the temperature of the vapor circulating therethrough. The tubular member may be hollow or filled with a porous filling material such as light meshed, nonwoven material, honeycomb or open-cell material and the like. The insertion of a filling material may increase the contact surface in the tubular member to enhance the cooling effect. The aerosol generating material may be a tobacco- based material such as reconstituted tobacco in any suitable form such as gathered sheet, strands, strips, powder, sponge, or foam.

In an embodiment said characteristic is a cutting edge of that layer such as previously mentioned. The cutting edge may vary as to its form. For example, the cutting edge may have a variation of curvature and/or inclination relative to the longitudinal axis of the consumable article. The cutting edge may have a variation according to a undulated, crenellated, or toothed pattern. The pattern may be varied in amplitude, period, width, and combinations thereof.

The rigidifying component is preferably a tubular component such as made of paper or cardboard. The wrapper can be made out of paper. The layer of glue, seam or bond or separation layer on, in or between the wrappers or rigidifying component, can be repeatedly produced during the manufacturing process of the aerosol generating article. The characteristic of the produced layers can therefore be used to identify the aerosol generating articles by a detection device of the aerosol generating device. Variations of the characteristic may be made on purpose or be inherent the manufacturing process or be amplified or reduced to modulate the detectability of the characteristic.

In a variant, the characteristic is a reduction or increase of the thickness of the wrapper or rigidifying component. The variation of the characteristic may enable to distinguish different types of article from others. In a variant, the at least one layer may comprise a conductive thread arranged in or on said at least one layer.

In a variant, said at least one layer comprises an insert having detectable optical and/or electrical characteristics.

Brief description of the drawings

Figure 1 shows a schematic representation of an embodiment of an aerosol-generating device of the invention, comprising an optical system to detect and process the image of a seam or glue layer of a consumable article;

Figure 2 illustrates a cross section of an aerosol generating article comprising a glue layer or glue layers according to the invention;

Figures 3 to 11 illustrate different embodiments of seam or glue layers of consumable articles according to the invention;

Figures 12a, b, c illustrate optical reflection and transmission configurations arranged to detect the presence and/or detailed properties of seam or glue layers of consumable articles according to the invention;

Fig.13 illustrates a device comprising a light source for illuminating, through an article, a seam or glue layer. The device comprises an imaging system configured to detect the presence and/or detailed properties of seam or glue layers of consumable articles according to the invention; Figures 14 illustrates an adaptation of the device of Figure 12 arranged so that at least two seam or glue layers may be detected;

Figures 15 illustrates the detection of an article comprising a seam and/ or glue layer that consist in a plurality of seam and/or glue layer portions. The detection of the presence or shape of a least two seam or glue layer portions is performed by a single detection system; Figure 16 and 17 illustrates a detection configuration, comprising several detectors, allowing to detect a seam or glue layer of the article independent of its angular orientation into an aerosol-generating device;

Figure 18 illustrates a detector configuration comprising a microlens array and a detector array;

Figure 19 illustrates a detector configuration configured to rotate a detector or detector system around a circumference of an aerosol-generating article;

Figures 20 and 21 illustrate articles that have a seam or glue layer comprising light incoupling areas and light outcoupling areas;

Figure 22 illustrate exemplary lateral cross-sections of seam or glue layers that have optical properties such as light focusing, light diverging properties.

Figure 23 shows the shape of a glue layer for detection that is present in a manufactured aerosol-generating article.

Detailed description of the invention

The present invention will be described with respect to particular embodiments and with reference to the appended drawings, but the invention is not limited thereto. The drawings described are only schematic and are non- limiting. In the drawings, the size of some of the elements may be exaggerated and not drawn on scale for illustrative purposes. The dimensions and the relative dimensions do not correspond to actual reductions to the practice of the invention.

The invention will be described in the following examples in relation to tobacco-based consumable articles but the scope of the invention shall not be construed as limited to tobacco based consumable articles but shall encompass any aerosol-generating consumable articles, such as smoking articles, heat-not- burn articles, e-liquid cartridges and cartomizers, which comprises an aerosol- generating substrate capable to generate an inhalable aerosol upon heating. Aerosol-generating articles 1 , or articles 1 , of the invention are also defined herein as consumables or consumable articles.

As used herein, the term "aerosol-generating material" refers to a material capable of releasing upon heating volatile compounds, which can form an aerosol. The aerosol generated from aerosol-generating material of aerosol generating articles described herein may be visible or invisible and may include vapours (for example, fine particles of substances, which are in a gaseous state, that are ordinarily liquid or solid at room temperature) as well as gases and liquid droplets of condensed vapours. The aerosol generating material may be a tobacco-based material such as reconstituted tobacco in any suitable form such as gathered sheet, shredded, sponge or foam.

The term “wrapper” is defined broadly as any structure or layer that protects and contains a charge of aerosol-generating material, and which allows to handle them. It has an inner surface that may be in contact with the aerosol generating material and has an outer surface away from the aerosol-generating material. The wrapper 3 may preferably comprise a cellulose based material such as paper and/or cellulose acetate. The wrapper 3 may also be made of a biodegradable polymer or may be made of glass or a ceramic. The wrapper 3 may be a porous material and may have a smooth or rough outer surface 5 and may be a flexible material or a hard material.

As used herein the term “constituents” refers to the detailed composition of the aerosol generating substance, for example tobacco, aerosol formers, binders, flavouring agents, nicotine, and combinations thereof. An aerosol-forming substrate may be provided in a stable support. Such a support may be in the form of a powder, granules, small strips, sheets, or foam.

A manufactured aerosol-generating consumable article 1 may have a cross section of any regular or irregular shape, and can have, for example, an elliptical or circular cross-section, defined in a plane orthogonal to a longitudinal axis. Articles define a lateral X-Y plane orthogonal to a virtual insertion axis Z (Fig.1 ). As used herein, the term “advanced image” or “processed image” means an image that has been modified by simple or complex image processing techniques and may be any image processing technique well known for extracting or enhancing or correlating features of 2D and/or 3D images. There is no limit to any particular image processing or correlation technique. The image processing techniques in the invention may be simple contrast enhancing techniques or very advanced image processing methods such as used in any high security detection systems, for example as used in banking or in fingerprint recognition. As used herein “a template” means a processed reference image or reference frame that is used to be compared or correlated with another processed images.

As used herein the term “glue layer” is defined as an adhesive layer for gluing two surfaces or layers or elements in an article 1. The term “seam” refers to a region where superimposed layers are seamed together such as by glue or any other attaching means. The term “bond” refers to a region where superimposed layers are attached one to another. Bonding may be realized by pure mechanical or stiction effects. For example, a “Velcro-like” layer comprising microscopic Velcro-type structures may be defined as a bond layer. Glue and seam layers may also be arranged as bond layers. The invention also encompasses separation layers, that are layers that are used as spacers to separate layers or elements.

A layer 10 herein is also defined as a reference layer, because it is used as a reference to its manufacturing characteristics. An article may have more than one reference layer, used in the identification process. A layer herein may be an outer or inner wrapping layer of an article 1. A sheet may be wrapped to form a tubular element or wrapper forming several superimposed layers. Two layers may be formed by superimposition of a wrapped element.

Fig. 2 illustrates a typical cross-section aerosol-generating article 1 comprising a layer 10 that is typically a glue layer 10. The article 1 comprises the further preferred elements 1 a-1 f: a consumable section T; - a consumable paper wrap 1a, for example a tobacco paper wrap 1a;

- a rigidifying element, preferably a paper tube 1 b;

- a hollow filter segment 1c, and a center hole segment 1c’, also defined as a cavity 1 c’;

- a combining plus wrap 1e arranged onto said wraps 1d’, 1d”; a filter segment 1h;

- plug wraps 1 d’, 1 d” that cover the filter segments 1c, 1c’ and filter segment 1h; - a tipping layer 1 f, typically a paper tipping layer 1f surrounding a central cavity 1g.

It is generally understood here that the layers 10 of the invention are layers that are usually formed during the production process of the articles 1.

The layer 10 of the invention may be arranged typically between or into or into the components or elements as described above for the example of the article illustrated in Fig.2, but other compositions of the elements and layers of articles are possible also. For example, it is understood that the layer 10 that is described herein may be annular and may have any extension along a circumference or a length of an article. A layer 10 must not necessarily have a centre of symmetry.

The manufacturing layer 10 as disclosed here may participate to at least one of the functions of: joining or adhesion; spacing between layers or elements; - mechanical or humidity protecting, wrapping, rigidification and/or separation;

- airflow or cooling;

- friction reduction or enhancement skin of a user; - optical and/or aesthetic functions.

In a first aspect the invention is achieved by a method of identifying a consumable 1 in an aerosol generating device 2. The method comprises the steps of:

- receiving a consumable 1 comprising identification information embedded on or in the device 2, the identification information being identifiable by identification means of the device 2;

- identifying the consumable 1 based on the identification information by the identification means.

The identification information is encoded by at least one variable characteristic that is identifiable by identification means of the device.

In embodiments, identification means comprise an optical reader comprising an image sensor, comprising an image detector, configured to make images of at least a portion of said layer 10. Identification means comprise preferably a control unit, which is configured to read information provided by the layer 10 and compare it to a set of authorisation information that is stored in a memory unit. In advantageous embodiments the memory unit may be configured so that it provides a compensation signals to allow minor deviations between the read information of the layer 10 and the authorized information on the layer 10. By allowing minor deviations, false rejections may be avoided. In variants, identification means may use a detector array without using imaging optics. In that case, the identification process is realized by the interpretation of intensities, colours or polarisation effects provided by the layer. Identification means that rely on detector arrays without imaging optics are more compact that imaging identification means, but have a lower resolution. On the other hand, optical readers that rely on detector arrays allow to provide a higher speed of identification than imaging systems that require focusing optics and more complex electronics to acquire and process images. The choice between identification means based on simple detectors or detector arrays and identification means that rely on imaging systems is a trade-off that depends on the type of layer 10 and its characteristic that is used for identifying a consumable, and also on other criteria such as the desired resolution, speed or cost of the optical reader.

In other variants, identification means may comprise a wireless communication system to read stored information that is stored in a data storage unit outside an aerosol-generating device. In advantageous embodiments, said dentification means comprise image processing electronics and data handling means such as image processing algorithms as further described herein.

The variable characteristic may be the simple presence or orientation of one or more layers chosen amongst: a glue layer or seam, a bond or separation layer for separating two layers of the consumable. The variable characteristic may be detailed geometrical and/or physical and/or chemical characteristics of such layer or layers 10, chosen amongst:

- the presence and/or shape of a layer 10, a thickness, a width, a cross section, a length of said at least one layer 10, surface or bulk properties of said at least one layer, such as roughness or brilliance, or textured features on the layer 10, the optical and/or electrical properties of said at least one layer 10, and combinations thereof.

In embodiments a non-uniform thickness or non-uniform width or non- uniform cross-section is detected. In an embodiment the characteristic is the presence or shape or orientation of an adhesive seam 10.

Adhesive layers are typical layers that have a variety of properties that are directly linked to a specific manufacturing process. Parameters that influence the physical and geometrical shapes, sizes volumes, surface properties, positions and distributions of adhesive layers are influenced by process parameters such as for example, but not exclusively: viscosity of the layer, the heating sequence and heating ranges, the presence of sizing agents, humidity. For example, the precise distance of a border of an adhesive layer and an upper edge of a plug- wrap paper is a variable characteristic that may be used as an indicator of the manufacturing process and its equipment. In an embodiment an adhesive or joining layer may be an intrinsically conducting polymer, known as ICP’s, which is a polymer that is electrically conducting without comprising metallic particles or metallic compounds.

In an embodiment, the characteristic is a cutting edge or a detectable systematic defect of said at least one layer 10. A glue layer or seam 10 for example may have a systematic cutting edge that may be used as an identification of the article 1. The characteristic may be the particular shape of such an edge. Typical edges of glue layer or seam or bond 10 are illustrated in the variants 102-108 of Fig.22. In addition, edges may have optical functions as described further herein. In an embodiment, the characteristic is the mechanical and/or electrical and/or magnetic property of a conductive thread arranged in or on said at least one layer 10.

In embodiments a layer 10 may be made, at least partially, electrically conductive by doping it with or by incorporating electrically conductive particles. The electrical conductivity along the length of a layer 10 may be used as the variable characteristic. For example, an adhesive layer or a glue layer may have a greater electrical conductivity over a first length of the layer than over a second length of the same layer. For example, the adhesive or glue layer bay be electrically conducting only over less than 30% of its total length and be non- conductive out of this limited length. The length of this electrically conductive portion may be used as the variable characteristic to identify the consumable 1.

In a variant, a layer 10 may be electrically conductive over a first length L1 and have less optical reflection over a second length L2. The combination of the information on the electrical property of said first length L1 and the optical property of said second length L2 may be used as a more complex variable characteristic to identify if the consumable 1 is a genuine product.

In an embodiment, the characteristic is the optical property of an insert arranged in or on said at least one layer 10. An insert may be arranged into the substrate of the article and may be arranged near or on a wrapper 3, 1f of the article 1. An insert may have a mechanical function to make an article 1 for example more rigid or to impose a certain form or cross section to the article 1. The insert may be an at least partially electrically conductive insert or may be made of an electrically isolating material. In an embodiment, the consumable 1 comprises an aerosol-producing substrate; and a wrapper and/or a rigidifying component and the characteristic is the one of an adhesive seam of the paper wrapper or rigidifying component. In a preferred mode, the rigidifying component is an inner tubular member covered by a wrapper. The inner tubular member may be a paper or polymer tube of thickness greater than the thickness of the wrapper. The tubular member may be positioned between an aerosol generating portion and a filter portion of the consumable article. The tubular member may have the function of longitudinally distancing the aerosol-producing substrate and the filter and so cooling the temperature of the vapor circulating therethrough. The tubular member may be hollow or filled with a porous filling material such as light meshed, nonwoven material, honeycomb or open-cell material and the like. The insertion of a filling material may increase the contact surface in the tubular member to enhance the cooling effect.

In an embodiment, said at least one layer 10 is an array of glue bands, as illustrated in the embodiments of Figures 3, 4, 5, 6, 8, 14 and 15. In an embodiment, said at least one layer 10 has non-uniform geometry in its length and/or its width. Figures 1 , 10 and 11 illustrate examples of layers 10 that have portions 10a, 10b having a greater width and/or thickness than the remaining parts of the layer 10. In variants, layers 10 may have at least a portion having a conical shape in a horizontal X-Z, Y-Z plane. The layer 10 as described herein may have several optical functions such as:

- optical transmission, as illustrated in Fig.12a an incident light beam 220 on a layer 10 is transmitted by the layer and provides a transmitted light beam 230 that may be a deviated transmitted light beam 230. In the example of Fig.12, a layer 10 has the shape of a parallel plate and deviates the light beam by a separation d because of the refraction effect of a parallel plate;

- deviation and reflection of an incident light beam 220: for example, as illustrated in Fig.12b, a layer 10 may deviate and reflect an incident light beam 220;

- as illustrated in Fig. 12 c, a wider layer than the layer illustrated in Fig.12b may enhance the effect of deviation of the transmitted light beam 230 and provide a reflected light beam 240 that leaves the layer 10 at a further distance to the incoming light beam 220.

Fig.15 illustrates an embodiment wherein a light source 200 provides a light beam 200 that illuminates at least two portions of a layer 20 so as to provide at least two identification signals. In embodiments, as illustrated in Figure 19 a detector configuration is provided to rotate a detector or detector system around a circumference of an aerosol-generating article.

In an advantageous embodiment, a layer 10 may have or optical diffusion and/or diffractive properties that may be used to identify the article 1. A glue or seam or bond layer may have a non-uniform structure so that at repetitive locations light may be deflected from the layer 10 and be directed to a light detector system 300. Light may be provided by a light source 200 that directs a light beam 220 to the layer 10 that comprises a plurality or a continuity of incoupling surfaces so that a portion of the light beam 220 is incoupled into the layer 10. At least a fraction of the incoming light beam 220 is reflected maximal twice inside the layer 10 to each of its sides and is outcoupled further in the layer 10. Fig.20 represents schematically the transfer of a directed light beam 220 to a detector system 300, in proximity of the light source 200, 220 by 1 to 4 internal reflections of the light beam 221 inside the layer 10. Limiting the number of reflection to maximum 4 allows to provide a detector that is in proximity of the light source. A detector system 300 may be configured to detected outcoupled light provided by more than one outcoupling area. In a first position of the article 1, light is incoupled in said layer 10 by a first incoupling area A and a light beam 230 undergoes one or two reflections and is outcoupled and detected by a detector system 300, which provides a first detector signal IA (Fig.21). The internal reflection of a light beam in a layer 10 may be enhanced by a reflection layer that may be arranged to a layer, such as a metallic coating layer, not illustrated in Figures. A detector system may be arranged at different locations along a glue layer 10 , and in variants more than one detector system 300 may be arranged in front of outcoupling areas of a light-guiding layer 10. In the embodiments illustrated in Fig.21 light is transferred by maximal 4 internal reflections in the layer 10. The incoupling and outcoupling (A-D) areas may be configured to constitute a recognizable and unique pattern. For example, a detector system 300 may detect 4 outcoupled light beams and provide a signal comprising 4 intensity steps as illustrated in Fig.21. Providing different in-and outcoupling areas allows to reduce the dependence on the insertion precision of an article in a device. An embodiment, such as the example represented in Figs. 20 and 21 , may be easily realized by adapting the variations of the width and/or thickness and/or the rugosity of portions of a glue layer 10. For example, a glue layer 10 may be realized in production so that it comprises a regular pattern of simple ridges that may provide the function of incoupling and outcoupling (A-D) areas. Such incouplers and outcouplers A,B,C,D arranged in a layer 10 of an article 1 may also be realized by imposing a slight prismatic shape that can be easily replicated in the manufacturing process of the article 1 . In variants, incoupling surfaces may have also the function as outcoupling surface, which is the case in the example of Fig.21. In variants, incouplers and outcouplers may be different areas or shapes or structures arranged on said layer 10.

It is understood herein that light beams 220 as used in the invention may be ambient light or light provided by a light emitting system 200 as illustrated in Fig.13. A light emitting system 200 comprises a light source 210 that may be a UV, visible or infrared light source. A light source having shorter wavelengths than the wavelengths of UV light may be used. Due to the very limited space available in aerosol-generating devices, light sources 210 are preferably semi conductor light sources such as LEDs, SLEDs or semiconductor light sources .

The light source 210 in the invention may be an infrared light source that may be the heater of the aerosol-generating device 2.

Light sources and light detectors may be arrays of light sources, not illustrated in the figures, and arrays of light detectors 310 as illustrated in the embodiment of Fig.18.

The light sources and detectors may be arranged in different places in a device 2. For example, Fig.13 illustrates a configuration wherein at least one light emitting system 200 is arranged opposite to the detector system 300. In such a configuration the layer 10 of the article is illuminated by light that crosses a diameter of the article 1. Said crossing of light may be realized by direct transmission or diffusion of light, in function of the optical properties of the substance or layers that are in the light path of the crossing light beam. In embodiments as illustrated in Fig.14, more than one seam or glue layer 10 may be detected by the detector system 300 that comprises preferably an imaging system to provide an image in an image plane 400. The detection system may comprise a CCD camera. Fig.16 illustrates a detection system comprising a plurality of detectors

302, 302’, 302”, 302’” so that the presence and properties of the layer 10 may be detected independent of the angular orientation of the article, said orientation being defined in a lateral X-Y plane. The detectors may be distributed circumferentially around the article such as at a certain angular path (e.g. 90 degrees).

It is now briefly described how said characteristics may be detected or imaged and used in the identification method of a consumable 1.

The identification of the identification information that is encoded by at least one variable characteristic as described herein, may be detected by identification means of an aerosol-generating device 2. The identification means are preferably, but not necessarily, optical detection means. Indeed, in embodiments said optical detection means may imply simple detectors or may require an imaging system 300 for providing and processing an image 400 of said characteristic of said at least one layer 10. During the manufacturing process the articles 1 may also be detected during or after their introduction in a package. The characteristics of said layer 10 may be well known from the manufacturing process and may not vary with time or they may vary according to well-determined production cycles.

Therefore, there are at least two methods (I, II) to generate a reference of the characteristic of said at least one layer 10:

- I) either the characteristic is well known and is always present in a consumable. For example, a well-known width or shape or thickness that is characteristic of the layer 10 and does never vary. Information on it is stored preferably in storage means in devices 2, or II) the characteristic varies according to production run cycles and/or in function of time and the information on the characteristic is updated in devices. For example, if a production machine needs to undergo maintenance or modifications , production parameters may lead to a new characteristic variation of the properties of the layers 10, for example a new value of a width or thickness of the reference layer 10. Then, an update may be provided to a device. This update may be provided by a data transfer from a package to the device, or in variants, by a wireless transfer of information. This allows that a device may recognize at least two typical characteristics of a layer and identify that the article is genuine. For example if a layer 10 of a genuine product 1 has a central blob 10a (as illustrated in Fig.1 ) and this central blob 10 is displaced during a new production cycle, the device may recognize that both blob positions are valid and recognize the article as genuine, even if provided from different production cycles.

In embodiments, the method of the invention may comprise the following imaging steps:

- providing an imager 300 comprising image processing means and image correlation means,

- imaging the layer 10 in said at least one consumable section of the aerosol-generating article to form a 2D and/or 3D image of the layer 10 therein by said imager 300,

- processing, by said image processing means, said 2D and/or 3D image to form a digitalized 2D and/or 3D image representative of the characteristics of the layer 10, said image comprising characteristic optical information of the layer 10,

- correlating, by said image correlation means, said current digitalized image with a reference image of said layer 10 in said consumable section registered during production thereof, said reference image comprising also characteristic optical information of the layer, - determining, based on the previous correlation results and a predetermined correlation criterion, if the aerosol generating article 1 is a genuine product.

Typical features to be extracted from the images of the layers 10, or a portion of the layers 10, are typically : lines, edges, ridges and localized interest points such as corners, directions, curvatures, cross sections, crossing lines, blobs, or points. The defects or systematic variations of properties of layers 10 in an article are typical sub-mm sized, preferably smaller than 200pm and typically between 30 pm and 50pm. Typical, but not exclusive, feature extraction techniques are the following: minutiae extraction, ridge and valley detection, orientation extraction.

Image processing comprising feature extraction techniques are well known in the field of 2D and 3D image processing and are not further described here. It is referred therefor to the following publications that are incorporated herein in their entirety:

- R.Szeliski, Computer vision: Algorithms and Applications, Springer Verlag, 2010, ISBN 978-1848829343 ;

- J.R. Parker, Algorithms for image processing and Computer Vision (2 ^nd ed.), Wiley, 2011, ISBN 978-0470643853; - N.Mark, A.Aguado, Feature Extraction and Image Processing for

Computer Vision (4the ed.), Academic Press, 2019, ISBN 978- 0128149768.

After pre-processing and feature extraction, at some point in the processing, a decision has to be made about which image points or regions of the image of a layer 10 are relevant for further processing. Such decision is made upon the known properties of typical statistical properties of layers 10 such that are provided during the manufacturing of consumable articles 1. Matching of sample images and production images may be based on a data reference that is stored in a device. Such data may be updated regularly, for example by providing wireless information to a device. Matching is typically and preferably based on the correlation of at least one of : minutiae, lines or ridges or black and white areas, 3D features (depth at a pixel for example), number of bifurcations etc. Matching of 2D and 3D images is a well-known technique and is not further described here in detail.

The method of the invention relates preferably as well to optical, capacitive, ultrasonic, thermal imaging detection techniques, or a combination of them.

Capacitive detection methods are based on a capacitive coupling that may measure and recognize any layer 10 that is at least conductive or that has a dielectric.

Ultrasonic imaging techniques may also be used, as they allow to recognize the presence and shape of at least a portion of the layer 10 by sending a sound wave at a particular frequency and tuning that frequency in for the sound wave’s reflection.

Thermal imaging may be deployed also and are similar to optical techniques, with the difference that thermal effects are detected. The heater in an aerosol-generating device may be used to generate the heat source to provide an infrared image.

In a second aspect the invention also provides an aerosol-generating system comprising an aerosol-generating device 2 and an aerosol-generating consumable article 1 , also defined as consumable, that is inserted, at least partially, in said aerosol-generating device 2. The consumable article 1 comprises at least one layer 10 as described herein.

In another aspect, the invention is also achieved by a consumable 1 for use with an aerosol-generating device 2. The consumable 1 comprises: - an aerosol-producing substrate arranged inside a rigidifying tube 3 and

- a wrapper and/or rigidifying component, and

- identification information encoded for identifying the consumable in the aerosol-generating device wherein the identification information is encoded by at least one variable characteristic identifiable by identification means of the device.

The at least one variable characteristic is representative of different arrangements of at least one layer in the aerosol-generating consumable article 1 chosen amongst: a seam, a bond, a cut, perforation, a variable thickness , the optical and/or electrical properties of said at least one layer, and combinations thereof.

In an embodiment the consumable 1 comprises an aerosol-producing substrate 3; and a wrapper and/or rigidifying component and the characteristic is an adhesive seam 10 of the wrapper or rigidifying component. In an embodiment the characteristic of the article 1 is a cutting edge of the adhesive or bond or glue or seam layer 10 of the wrapper or rigidifying component.

In an embodiment the characteristic of the article may be a perforation or perforations or defects in a layer 10 arranged to a wrapper or other layer or a rigidifying component present in the article.

The wrapper may be a paper wrapper such as a tipping paper or plug wrap for wrapping different portions of the article such as a tobacco rod, tubular member and/or filter segments. The rigidifying member can be a paper tubular member and may be positioned between the tobacco and the filter or be part of the filter.

In an embodiment the characteristic of the article is a variation of the reduction or increase of the thickness of any layer 10 as described herein. Thickness is preferably defined orthogonal to said virtual insertion axis Z and may also be a thickness determined in said Z-axis.

In an embodiment said at least one layer 10 comprises a conductive thread arranged in or on said at least one layer 10. The conductive thread must not necessarily have the shape of a wire and may be a flat-shaped structure. In variants said at least one layer comprises an insert having characteristic optical and/or electrical properties.