Aerosol generating system and device having a waveguide arrangement for authenticating an aerosol product - Patents.com

Abstract

The present invention relates to an aerosol generating system including an aerosol product (1) including indicia (4) disposed on the outer surface of the aerosol product (1) and an aerosol generating device (2) usable with the aerosol product (1). The aerosol generating device (2) includes a cavity (2a), a heater, and an optical reading system. The cavity (2a) has an accessible opening in its outer body and is configured to receive, upon insertion, a consumable product (1) including indicia (4) disposed on the aerosol product (1). The optical reading system includes at least one waveguide (10) including an in-coupling surface (12) and an out-coupling surface (14), and a detector (30). The waveguide (10) is configured to illuminate the indicia (4) in the cavity (2a) with a light beam (400) and transmit a light beam (100) provided by the indicia (4) to the detector (30) of the optical reading system. The present invention also relates to a method for authenticating a consumable item (1).

Description

[Technical field]

[0001] The present invention relates to the field of aerosol generating products, more particularly to an aerosol generating system, in particular an electrically heated e-liquid system or an electrically heated aerosol generating system, comprising an electrically powered device configured to generate an aerosol from a solid and / or liquid aerosolizable substrate insertable into the device. [Background technology]

[0002] In recent years, electronic cigarettes based on aerosol-generating consumables have become increasingly popular. There are two main types: liquid vaporizers and heated tobacco inhaler devices. Heated tobacco inhaler devices are referred to as "heat-not-burn" (HNB) systems. HNB systems provide a more realistic tobacco flavor compared to electronic cigarettes, which deliver an inhalable aerosol by heating a liquid charge containing an aerosol former, flavorings, and often nicotine. The working principle of HNB systems is to heat a substantially solid tobacco-containing material containing aerosol-forming substances (such as glycerin and / or propylene glycol), which vaporize during heating at 200-400°C, lower than the normal combustion temperature of conventional cigarettes, to produce a vapor that extracts nicotine and flavor components from the tobacco-containing material. Inhaler devices are typically portable heaters that are configured to accept consumables, particularly rod-shaped articles.

[0003] The fraudulent trafficking of aerosol-producing products is a problem, whether the aerosol-producing product is a standard cigarette, e-liquid, or HNB product, since counterfeit products may be of particularly low quality or, in the case of e-liquid or HNB consumables, may not be suitable for a particular smoking system. To identify whether an aerosol-generating consumable is genuine, a code or equivalent marking containing information about the product may be placed on the outer surface of the product to be detected during or before use in a particular device. This makes it possible to confirm the authenticity of the consumable and, in case of a negative determination, to switch off the heating system in which the consumable is used. To perform accurate authentication of codes on consumables such as HNB products, the recognition probability must be very high so that suitable products are not rejected. However, existing indicia are limited to the low density of information that can be contained in the indicia, and most known indicia rely on classical codes such as one- or two-dimensional barcodes that can be easily imitated without the use of special optical equipment, for example by simply visualizing the code with the human eye.

[0004] Various attempts to provide an authentic aerosol product have already been proposed in the prior art. For example, US20190008206A1 discloses a smoking article including indicia on the outer surface of the smoking article, which indicates the type of smoking article and can be in the form of a pattern or one-dimensional and two-dimensional barcodes. The indicia include different gray levels that can be produced by printing dots of smaller size. Such indicia are easily detectable and reproducible and may contain only low density information or need to be provided at an unacceptably large size. The system described in US20190008206A1 is limited to a simple optical reader with a detector in close proximity to the indicia due to lack of space. Also, the optical reader of US20190008206A1 cannot be used near the heater of the device because the detector of the reader may be damaged, which limits the locations on the smoking article for placing the indicia.

[0005] US20160302488A1 describes a smoking article that includes indicia on the outer surface of the smoking article. The indicia can be in the form of a one-dimensional / two-dimensional barcode. The code includes a distinguishable spectroscopic signature of a layer of indicia applied by spraying. The spectroscopic signature is detected by an optical reader, a single optical reader located in a very limited space and close to the cavity of the smoking device. Due to the lack of space, only simple optical filters can be used, and therefore the system described in US20160302488A1 is limited to simple spectral or color detection only, or to the use of one or more narrow band filters. The spectral effects provided by the system of US20160302488A1 are therefore easy to mimic or reproduce.

[0006] In WO2019129378A1, an aerosol generating consumable for an inhaler is described, which includes indicia containing information about the consumable. The information is read by an optical reader, which is a simple detector system due to lack of space. The device in WO2019129378A1 also relates to a system in which a heater is arranged to be located on the central axis of a cavity for introducing the consumable. Also described is an inhaler, which includes an optical reading system for reading indicia on the consumable. The indicia is in the form of a simple one- or two-dimensional barcode. The system is not suitable for heaters located on or in the walls of the cavity, as the optical detectors may be damaged by high temperatures. Also, due to the configuration of the device in WO2019129378A1, the indicia may be just a simple code that can be easily imitated to be visible to the naked human eye.

[0007] Therefore, there is a need for improved techniques to enable authentication of aerosol-produced articles such as HNB, inhalation articles and smoking articles. In particular, authentication based on codes or indicia with much higher information density is preferred to improve the quality of authentication and make the articles harder to counterfeit. It is also further desirable that at least the detector portion of the optical reader be maintained below 50° C., typically at room temperature. Prior art systems are limited to simple codes, as only simple optical readers are available and require indicia that cannot be located in close proximity to the heater of the smoking device. Summary of the Invention [Means for solving the problem]

[0008] The inventors of the present invention have found a solution to the above-mentioned problems by providing an aerosol generating system including an aerosol generating device with improved placement of an optical reader within the very limited space available in such a device. Furthermore, in an embodiment, the present invention makes it possible to provide indicia that can be placed in close proximity to a heater of a smoking device. The device of the present invention additionally makes it possible to provide a solution for detecting and identifying information contained in indicia that may contain high density coded information and that cannot be read by simple optical readers that cannot be placed in close proximity to or in contact with a cavity of a smoker device arranged to receive an article containing such indicia.

[0009] The present invention therefore relates to an aerosol generation system according to independent claim 1. The aerosol generation system of the present invention comprises an aerosol product, hereinafter also called consumable, extending along a longitudinal axis, the aerosol product comprising at least one indicia arranged on a surface of the aerosol product comprising information about the product. The aerosol generation system comprises an aerosol generator arranged in an outer body part, the aerosol generator comprising a power supply section, a cavity, a heater, an optical reading system, and further comprising at least one photodetector and a control unit configured to instruct the heater and the optical reading system. The cavity has an accessible opening in the outer body part, the opening configured to receive a consumable comprising indicia arranged on a surface of the product upon insertion of the product, the heater being arranged to heat the consumable.

[0010] According to the invention, the optical reading system includes at least one waveguide including an in-coupling surface and an out-coupling surface. The aerosol generating device is configured to illuminate the indicia on the aerosol product with an illumination light beam, such that the indicia interacts with the incident light and transmits guided light to an out-coupling surface arranged to reflect at least a portion of the illumination light to the in-coupling surface and guide the in-coupled light to the at least one detector. A control unit is configured to instruct the optical reading system to authenticate the consumable product based on information contained in the reflected light beam.

[0011] In an embodiment, an input coupling structure may be disposed at the input coupling surface of the waveguide. Similarly, an output coupling structure may also be disposed at the output coupling surface of the waveguide.

[0012] In such a case, at least a part of the input coupling structure and / or the output coupling structure may be selected from diffractive structures, planar or curved wedge-shaped sections of a waveguide, arrays of microprisms, holographic layers, metasurfaces, electrostatically addressable micro-mirrors or micro-shutter arrays, lenses, mirrors. In a preferred embodiment, diffractive structures are used for the input and output couplers, since they may be integrated into a part of the surface of the waveguide during the same manufacturing process of the waveguide. Diffractive input and output couplers may be designed to couple light into or out of a waveguide with a relatively poor efficiency, i.e., below 60% or below 80%. More preferably, the diffractive input or output couplers are designed to have an optical function, such as a focusing function, so that imaging can be achieved without a lens. Furthermore, the diffractive input coupler may couple light into a waveguide such that the central optical axis of the coupled-in light beam is at an angle to the normal direction of the diffractive input coupler. In a variant, light can be coupled in according to different diffraction orders, i.e. +1 or -1, or +2 or -2. In a further variant, a single diffractive input coupler can couple light into a waveguide such that the light propagates according to two opposing guided beams that are each coupled out by two separate output couplers. This can be used to identify indicia that provide information according to opposing polarization directions, each of the polarized beams being coupled out by at least two diffractive output couplers and detected by at least two separate detectors, thereby providing highly secure authentication.

[0013] Furthermore, such input coupling structures and / or output coupling structures may be configured to focus and / or deflect a light beam incident on said input coupling structure and / or output coupling structure in at least one plane (XY, XZ, YZ).

[0014] In one embodiment, the input coupling structure and / or the output coupling structure are achromatic structures providing the same input coupling, output coupling efficiency and / or focusing, respectively, in a spectral band of at least 50 nm, preferably at least 100 nm, more preferably at least 200 nm.

[0015] In some embodiments, the input coupling structure and / or the output coupling structure has a focal length equal to or greater than the length L of the waveguide. Preferably, the length L of the waveguide is less than 100 mm, preferably less than 60 mm, even more preferably less than 30 mm. The thickness of the waveguide is less than 500 μm, preferably less than 100 μm, even more preferably less than 50 μm, or less than 20 μm. In an embodiment, the input coupling structure and / or the output coupling structure has a focal length less than the length L of the waveguide. An advantageous embodiment then provides a waveguide with absorbing or diffusing walls, such that total internal reflection occurs at the thin walls of the waveguide, and total internal reflection occurs only at the wall with the greatest width. In an embodiment, the thickness of the waveguide, measured perpendicular to the length L of the waveguide, is less than 1 / 10, preferably less than 1 / 50 of the width of the waveguide.

[0016] In an embodiment, the waveguide has a parabolic refractive index profile so that images can be transmitted more efficiently or with less image distortion.

[0017] In an embodiment, the waveguide may have a Y-shape and have one input coupling branch and at least two output coupling branches, allowing detection of complex information, such as that provided by two differently polarized beams from an indicia.

[0018] In an embodiment, the input coupler and / or output coupler may be configured to provide an optical function, such as the optical function of a cylindrical lens. Input and output couplers that focus only in one plane provide a solution for detecting one-dimensional codes and allow not to involve total internal reflection at the thin sidewalls of the waveguide.

[0019] In an advantageous embodiment, the waveguide is a rigid or flexible hollow waveguide, which makes it possible to guide light over distances typically less than 1 m, such that light with a broad spectral distribution, such as visible and infrared light, can be guided, since the hollow core has a refractive index substantially equal to 1 for a vacuum or a gas such as air.

[0020] In a variant, the core and / or cladding of the hollow waveguide may be composed of at least two layers. The mechanical and optical properties of the waveguide may be non-uniform along the length of the waveguide. In a variant, the waveguide may be disposed in a solid or flexible tube.

[0021] In other embodiments, the input coupling structure and / or the output coupling structure have a focal length shorter than the length L of the waveguide, and a focusing structure is disposed on at least one side of the waveguide, the focusing structure being configured as a relay structure for transmitting an image from at least a portion of the indicia to an output coupling surface or a certain distance away from the output surface and out of the waveguide.

[0022] In one embodiment, the waveguide is an optical fiber or optical fiber bundle. The use of optical fibers makes it possible to provide a very inexpensive, commercially available waveguide that can be easily wrapped and positioned in or through tight spaces or openings.

[0023] In one embodiment, the waveguide is a planar optical waveguide, and may be a flexible waveguide. The use of a planar optical waveguide allows the transmission of images from the out-coupling surface to the out-coupling surface.

[0024] The waveguide of the aerosol generating device of the present invention can be made of different materials depending on the design and performance needs of the device and the characteristics of the indicia to be read on the aerosol product. For example, the waveguide can be made at least in part of polysiloxane, a polymer containing imide groups, polyamideimide, or polyimide.

[0025] In one embodiment, a light focusing element is disposed between the cavity and the in-coupling surface. By using a focusing element disposed between the indicia and the in-coupling surface of the waveguide, it is possible to project at least a partial image of the indicia onto the in-coupling surface.

[0026] In one embodiment, the light focusing element is part of the waveguide. By integrating a focusing element onto or within the waveguide, it is possible to provide a monolithic component that focuses and directs light into the waveguide. Such a monolithic arrangement reduces the space required and cost of the optical reader and improves the stability and reliability of the optical reader.

[0027] In one embodiment, the waveguide is arranged to transmit a magnified image of at least a portion of the indicia to the out-coupling surface or out of the waveguide. By using a waveguide that provides magnification of the guided light beam, it is possible to avoid using additional optical elements to achieve magnification. Such an arrangement reduces the space required and the cost of the optical reader and improves the stability and reliability of the optical reader.

[0028] In one embodiment, the waveguide is at least partially wrapped around a length of the cavity. A wrapped waveguide makes it possible to provide a solution where long lengths of guided light are required. A wrapped waveguide makes it possible to provide the possibility of including more than one in-coupling and / or out-coupling surface of the waveguide, and also provides the possibility of arranging multiple indicia to realize such a waveguide.

[0029] In one embodiment, at least a portion of the waveguide is configured to transmit light provided by an emitter to the indicia. By configuring the waveguide or waveguide bundle so that it also transmits light to the indicia, it is possible to avoid illuminating optical elements located between the light source and the indicia. It is also possible to provide a light source that does not need to be located close to the indicia.

[0030] In an embodiment, at least a part of said waveguide is realized on at least one of the surfaces of a heater of the heater system.

[0031] In one embodiment, the detector is a detector array. The use of a detector array offers the possibility to detect multiple intensity or color effects provided by the indicia.

[0032] In one embodiment, at least one optical filter is disposed between the out-coupling surface and the detector. The use of an optical filter makes it possible to detect a color or spectral effect provided by an indicia.

[0033] In one embodiment, an optical spectrometer is disposed between the output surface and the detector. The use of an optical spectrometer makes it possible to detect narrow spectral effects provided by indicia.

[0034] In one embodiment, the detector includes an image processor. A detector including an image processor may be used to provide an image of at least a portion of the indicia.

[0035] A second aspect of the present invention further relates to a method of authenticating a consumable product, comprising: Providing an aerosol generating device as described above and a consumable product including indicia disposed on an exterior surface thereof; inserting at least a portion of a consumable including indicia into a cavity of an aerosol generating device; illuminating indicia on an exterior surface of the consumable, collecting reflected light from the indicia with a waveguide, and directing the reflected light to a detector of an optical reading system; authenticating the consumable by calculating information contained in the reflected light that strikes a detector in the control unit; Includes.

[0036] In one embodiment, the method further comprises the step of commanding the heater using the control unit based on the information calculated in the authenticating step. [Brief description of the drawings]

[0037] [Figure 1] 1 shows a schematic cross-sectional view of a waveguide including a diffractive input coupling structure and a diffractive output coupling structure. [Diagram 2] 1 shows a schematic cross-sectional view of a waveguide including a holographic input coupling structure and a holographic output coupling structure. [Diagram 3] 1 shows a schematic cross-sectional view of a waveguide including a wedge-shaped in-coupling surface. [Figure 4] 1 shows a schematic diagram of an aerosol generating device manufactured according to an embodiment of the present invention, showing consumables inserted into the device. [Diagram 5] 1 shows a schematic diagram of an aerosol generating device manufactured according to an embodiment of the present invention, showing consumables inserted into the device. [Figure 6] 1 shows a schematic diagram of a manufactured aerosol generating device according to an embodiment of the present invention, showing a consumable inserted into said device, in which the waveguide includes a light focusing element that is part of the waveguide. [Figure 7] 1 shows a schematic diagram of a manufactured aerosol generating device according to an embodiment of the present invention, showing a consumable inserted into said device, in which the waveguide is configured in a helical wound arrangement. [Figure 8] FIG. 1 shows a schematic diagram of an aerosol generating device manufactured according to an embodiment of the present invention, showing a consumable inserted into said device. An embodiment of the aerosol generating device includes a reflective mirror positioned to direct light provided by a portion of the smoking article to an input face of a waveguide. [Figure 9] 1 shows a schematic cross-sectional view of an aerosol generating device manufactured according to an embodiment of the present invention, showing a consumable article inserted into said device, the embodiment including a waveguide disposed along at least a portion of the circumference of the article when inserted into the device. [Figure 10] 1 shows a schematic diagram of a manufactured aerosol generating device according to an embodiment of the present invention, showing a consumable inserted into said device. The embodiment includes a waveguide including a side in-coupling surface facing indicia of the article. [Figure 11]1 shows a schematic diagram of a manufactured aerosol generating device according to an embodiment of the present invention, showing a consumable inserted into said device. The embodiment includes a waveguide including an edge in-coupling surface facing the indicia of the article. [Figure 12] 1 shows an aerosol generating device according to an embodiment of the present invention. [Figure 13-16] 1 illustrates an embodiment of an aerosol generating device according to another embodiment of the present invention. [Figure 17] An exemplary implementation is shown. [Figure 18-19] 18 shows an enlarged cross-sectional view of the device of FIG. 17. [Figure 20] 1 shows a cross-sectional view of a binary diffractive structure. [Figure 21] A cross-sectional view of a four-stage diffraction structure is shown. [Figure 22] 1 shows a cross-sectional view of a blazed diffractive structure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0038] The present invention relates to an aerosol production article 1, an aerosol generating device 2, and a system including the article 1 and the device 2.

[0039] The present invention will be described with reference to particular embodiments and the accompanying 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 to scale for illustrative purposes. The dimensions and relative dimensions do not correspond to actual reduction to practice of the invention.

[0040] Although the present invention will be described in the following examples in relation to a tobacco-based consumable 1, the scope of the present invention is not to be construed as being limited to tobacco-based consumables, but rather to encompass any aerosol-generating consumable, such as smoking articles, heat-not-burn cigarettes, e-liquid cartridges, and cartomizers, that include an aerosol-generating substrate capable of generating an inhalable aerosol upon heating. A tobacco-based consumable does not necessarily have an axis of symmetry and may have any form or shape, such as an elongated shape, such as a cylindrical shape, or a spherical shape, or a beam shape. The tobacco-based consumable 1 of the present invention includes a portion 1a on the smoker's side, including at least one portion 1b on which the indicia 4 is located. The article 1 includes a further portion 1c that does not include the indicia 4. The indicia 4 may be located on at least one side of the further portion 1c.

[0041] As used herein, the term "aerosol-generating material" refers to a material capable of emitting an aerosol stream containing volatile compounds upon heating. The aerosol generated from the aerosol-generating materials of the aerosol product articles described herein may be visible or invisible and may include vapor (e.g., fine particles of a substance in a gaseous state that is normally a liquid or solid at room temperature) as well as droplets of gas and condensed vapor.

[0042] As used herein, the term "diffractive structure" refers to a structure that includes a diffractive element or a diffractive structure. Diffractive structures are broadly defined and include metasurfaces.

[0043] As used herein, the term "holographic" refers to an element or layer that acts as a hologram when illuminated with light.

[0044] As used herein, the terms "input coupling" and "output coupling" refer to the input coupling of light into and out of a waveguide, respectively. The input coupling is realized by the input coupler 11. The output coupling is realized by the output coupler 13. As used herein, the input coupler and the output coupler are part of the waveguide 10. Preferably, the input coupler 11 and the output coupler 13 are structural parts of the waveguide 10. For example, the structural parts can be wedge-shaped parts or any refractive, reflective or transmissive structure. It is understood that the input coupling and / or output coupling of light can be done by non-structured areas 12, 14 of the waveguide, which is a simpler solution but has a lower input coupling and output coupling efficiency compared to the case where the input coupler 11 or the output coupler 13 is provided, such as by using a diffractive input coupler 11 or a diffractive output coupler 13. The input coupler 11 and / or the output coupler 13 can be non-structured areas 12, 14 of the waveguide. Also, the input coupling surface or region 12, 14 may be an edge of the waveguide 10 (FIG. 3) or any curved or non-curved portion of the side of the waveguide 10. The input coupling provides at least one guided light beam 100, which may be a monomode or multimode light beam propagating inside the waveguide 10 to the output coupling surface 14 or output coupler 13 of the waveguide 10. The input coupling element 20 and the output coupling element are defined as elements that are not part of the waveguide 10, but are elements positioned outside the waveguide 10 and are adapted to improve the input coupling of light to and the output coupling of light from the waveguide 10. The input coupling element and the output coupling element may be the same element, which may be, but is not limited to, an optical lens, a prism or a mirror, or a combination thereof. The input coupling element and the output coupling element may be an array of optical elements, such as an array of microprisms. The input coupling element 20 and the output coupling element may be electrically addressable elements. The input and output coupling elements may be addressable elements, such as, for example, MEMS mirrors or electro-optical elements adapted to be scanned or switched.

[0045] As used herein, the term "waveguide system", also defined as an optical reading system, refers to a subsystem of the aerosol generation device 2 that includes a photodetector and at least one waveguide positioned to collect optical information provided by a smoking article and configured to transmit the optical information to the detector. The waveguide system may include optical input and / or output coupling elements that are separate from the waveguide 10 or integrated on or within the waveguide 10.

[0046] The term "longitudinal axis of waveguide 10" is defined as the imaginary central axis of waveguide 10, defined in the direction of guiding light beam 100 within waveguide 10. Optical guiding can be performed by total internal reflection (TIR) ​​or by using reflective or diffractive layers or structures.

[0047] The term "indicia 4" is defined as an element or structure that contains information about the smoking article, and is usually located on the outer surface of the article. The indicia 4 may be embedded within the article 1. The indicia 4 may be of different types, some of which are described in more detail below. Exemplary types of indicia 4 that may be applied to the aerosol product article 1 according to the present invention include, but are not limited to: Reflective signs 4; Diffractive signs 4; Reflective and diffractive markings 4; an indicium 4 including at least one indicium waveguide; the term "indicium waveguide" refers to a waveguide, such as a resonant waveguide grating, disposed on or within the indicium 4 of the article and distinct from the waveguide 10 of the aerosol generating device described herein; an indicium 4 including at least one indicium resonant waveguide 10; Partially transparent sign 4; Indicia that are an ordered or distributed arrangement of chemical substances embedded in an article; Typical type of sign 4 different types of combination Includes.

[0048] The indicia 4 described herein may be arranged to provide a certain direct reflection effect, such as providing multiple light beams that may have different spectra and / or different angles of reflection, when illuminated by the light beam 400. For reasons of clarity of illustration, the illumination light beam 400 or light beams are not shown in all figures. The reflected light beam may be a diffracted light beam projected in any diffraction order. The indicia 4 may include structures on at least one of its surfaces or sides, and may include structures embedded within a layer of the indicia 4. For example, a refractive structure may be provided on the outer surface of the indicia 4. The light beam described herein may be a parallel light beam, or may be a large diameter light beam, and may be a diverging or converging light beam. The light described herein may be high energy light with a wavelength of less than 180 nm, or UV light (i.e., UVA or UVB or UVC region of UV light with a wavelength of more than 180 nm), visible light, infrared light, or terahertz waves, or even microwaves. The waveguide may be a hollow core waveguide for guiding high energy light or microwaves.

[0049] The indicia does not necessarily have to be a code in the form of a physical structure such as a barcode, but may be a chemical substance that exhibits a spectral signature when illuminated by light beam 400. In such a case, waveguide 10 of device 2 may be used to transmit only the spectral information of light reflected or refracted from the chemical substance of indicia 4, i.e., without the need to transmit an image of indicia 4.

[0050] Preferably, but not necessarily, the code elements or structures of the indicia 4 are difficult or impossible to detect or distinguish individually by the human eye, so that the indicia cannot be easily read or imitated without the use of optical systems. The indicia 4 may be arranged according to a 2D or 3D arrangement of structures and may have any shape, such as a square or a rectangular strip that may be arranged all around the outer surface 5 of the article 1. Apart from anti-counterfeiting properties, the indicia 4 may desirably also contain information of certain parameters to be used by the inhaler device, such as an ideal temperature range, or a heating profile as a function of time, or parameters making it possible to provide the smoker with different smoking tastes or smoking intensities.

[0051] The use of the waveguide 10 makes it possible to provide an aerosol generating device 2 that can be positioned according to different types of indicia 4 as described. Furthermore, the use of the waveguide 10 makes it possible to provide such an aerosol generating device 2 with a high degree of design freedom, which addresses issues such as very limited available space and heating issues of the components of the required optical reading system.

[0052] As used herein, the term "in-coupling surface 12" should be understood as the area of ​​the waveguide 10 through which light enters the waveguide. This area can be a virtual surface on which an input coupler 11 is placed, such as, but in no way limited to, a refractive, diffractive, holographic, or metallic structure or array of structures. The input coupler 11 is also defined as a structure that allows light to be guided into the waveguide 10 so that the light propagates as a guided light beam 100, i.e., an input coupling structure. In certain cases, an input coupling surface may be arranged to serve as the input coupler 11. In other cases (FIGS. 1 and 2), the input coupler 11 may face the input coupling surface 12.

[0053] Furthermore, the term "output coupling surface 14" should be understood as an output coupling area where light leaves the waveguide 10, i.e. where at least a portion of the guided light 100 is coupled to a medium outside the waveguide 10. The output coupling area can be a virtual surface where an output coupler 13 is placed, such as, but not limited to, a refractive, diffractive, holographic, or metallic structure or array of structures. The output coupler 13 is defined as a structure that allows the guided light 100 in the waveguide 10 to be guided out of the waveguide 10. In certain cases, the output coupling surface 14 can be positioned to act as the output coupler 13. In other cases (FIGS. 1 and 2), the output coupler 13 can face the output coupling surface 14. As will be further explained, the input coupler 11 and the output coupler 13 can be areas at the side of the waveguide 10, or can be parts of the surface of the waveguide 10 that has a coating or has a wedge shape relative to the side of the waveguide 10. The input couplers 11 and output couplers 13 may also be micro- or nano-structured parts of a waveguide or dedicated input and output coupling layers, and are therefore defined as input and output coupling structures or as input and output coupling layers, respectively. The input couplers 11 and output couplers 13 may be static structures or layers, but also dynamic layers in the sense that they may have light direction properties that can be changed by the action of forces, such as electric forces, for example in the case of electrostatically actuated micro-shutters or micro-mirrors.

[0054] The term "detection system" includes means for converting optical information provided by indicia 4 of the smoking article 1 into electrical signals or data that can be used to identify information about parameters of the smoking article 1 and / or the aerosol generating device 2 to be used for said article 1. Optical information about the aerosol product article 1 can be provided by indicia 4 arranged on the smoking article 1, but also by at least a part of the smoking article, such as by a surface structure of said part or by any information embedded in or on said aerosol product article. Information can be embedded in or on said aerosol product article 1 by any physical or chemical means, as long as it can provide an optical effect, which can be a spectral and / or color effect and / or an intensity effect. The waveguide allows the optical effect to be transmitted to the detection subsystem during operation of the device.

[0055] Waveguide 10 The waveguide 10 described herein is configured to guide electromagnetic radiation, typically radiation having wavelengths including the UV, visible and full infrared (IR) regions.

[0056] The waveguide 10 can be of the following types, but is not limited to: A single-mode or multimode waveguide 10; Waveguide bundle 10; a waveguide 10 having a non-circular cross section defined perpendicular to a longitudinal axis of the waveguide 10; A waveguide 10 with a rectangular cross section. The planar waveguide preferably has a thin wall 10''' with a height t1 and has two faces 10', 10'' with a width t2 preferably greater than said height t1; The waveguide 10 may be made of non-flexible or flexible materials, or a combination of such materials; a waveguide 10 arranged to guide at least one illumination light beam and at least one guiding light beam 100 provided by the indicium 4; The waveguide 10 of the present invention may be a Y-shaped waveguide, may include optical couplers 11, 13, and may include more than two waveguide branches for collecting light from or providing light to the indicium 4; The waveguide 10 may be a hybrid and may include different types of waveguides, for example a planar waveguide over which a multimode fiber is disposed; The waveguide may be a hollow core waveguide, which is described in more detail below.

[0057] Planar waveguides, also defined as slab waveguides, are particularly well suited to forming one-dimensional images of indicia due to total internal reflection between the parallel planes of the planar waveguide. For example, a planar waveguide may be used to provide a 1D image of a series of parallel code lines arranged around the periphery of an article. An optical system using a planar waveguide arranged such that its length is orthogonal to the code lines may provide an image consisting of distinct elongated dots along an imaginary line.

[0058] By using waveguides with rectangular and square cross sections, it is possible to provide 2D images. To achieve this, the waveguide must rely on the so-called self-imaging effect. The image is not actually "transmitted" through the waveguide, it is only its phase distribution that repeats periodically along the length of the waveguide, whether it is a planar waveguide or any multimode fiber. By using a planar waveguide of a given length, the width and wavelength of the planar waveguide can be selected to satisfy the condition of self-focusing. The self-imaging effect in waveguides is described in the following publications: O. Bryngdale; Journal of Optical Society of America, vol. 63, nr. 4, 1973.

[0059] In an embodiment, at least two waveguides may be arranged one above the other, and at least one waveguide of such a hybrid arrangement may be configured to guide an illumination light beam for at least partially illuminating the indicia. This provides a configuration in which the illumination source and detector are located away from said indicia, for example in an area of ​​the device that, during operation, has a temperature lower than 100° C., possibly lower than 50° C. The type and dimensions and materials of the waveguide 10 are selected depending on the type of indicia 4 and the geometrical and operational temperature requirements of the aerosol generating device in which the waveguide 10 is implemented, and are typical, but not limited to, the following options: A single fiber 10 for transmitting intensity, polarization and spectral information; a fiber bundle 10 for transmitting an image and projecting a light beam; A planar waveguide 10 for the transmission of intensity, polarization, spectral information as well as the transmission of images and illumination light beams.

[0060] All embodiments herein may be adapted to direct an illumination beam provided by a light source disposed in waveguide 10 away from 4. This may be achieved by disposing an additional waveguide 13, which may be disposed within waveguide 10, or on waveguide 11, or which may be a separate illumination waveguide.

[0061] Optical fibers 10 and fiber bundles 10, such as those used in endoscopes, are well known to those skilled in the art of guided wave optics and will not be described further here. Methods for constructing suitable optical fiber arrangements for illuminating an object and collecting the light reflected or transmitted by such an object are also well known. This method is also described in the prior art and will not be described further. Since the information is contained in the Fourier transform function, it is also possible in principle to transmit a partial image by a single optical fiber. This is a more complex solution than the solution using planar waveguides, since it requires a more complex optical reader arranged to ensure, for example, calibration and / or polarization requirements, but this solution can also be implemented in an embodiment. Transferring an image at least partially by a single multimode fiber offers great benefits for different imaging applications where the available space is very limited and has been described, for example, in recent literature: A.Fertman, D.Yerlin: “Image transmission through an optical fiber using real-time modal phase restoration”;Journal of the Optical Society of America B,vol.39,pp.149-157(2013); P. Caramazza et al. “Transmission of natural scene images through a multimode fiber”, Nature communications, School of Physics and Astronomy, University of Glasgow, (2019)10:2029;https: / / dol.org / 10.1038 / s41467-019-10057-8 / www.nature.com / naturecommunications; VSFeschenko et al, “Optical imaging system with a waveguide,Physical and Quantum Optics,Optics and spectroscopy,vol.97,nr.3,2004,pp.468-471.

[0062] The planar optical waveguide 10 of the aerosol generation device 2 has geometric and functional advantages over simple optical fibers or fiber bundles, as will become apparent from the following description of various embodiments of the invention.

[0063] 1 shows a schematic cross-sectional view of a portion of a planar waveguide 10 including a diffractive input coupling structure 12 and a diffractive output coupling structure 14. Both the input coupling structure 12 and the output coupling structure 14 may be structured reflective gratings SRG1, SRG2. In an embodiment, more than one input coupling structure or output coupling structure 12, 14 may be arranged in the waveguide 10, and one of the input coupling structure 12 or the output coupling structure may be a transmission grating. In all embodiments of the present invention, the input coupling structure and / or the output coupling structure may be arranged on any side or edge of the waveguide 10.

[0064] FIG. 2 shows a schematic cross-sectional view of a portion of a planar waveguide 10 including a holographic input coupling structure 12 and a holographic output coupling structure 14.

[0065] Figure 3 shows a schematic cross-sectional view of a portion of a planar waveguide including a wedge-shaped in-coupling surface 12. In the embodiment of Figure 3, an internal at least partial deflection structure may be provided, as shown.

[0066] There is no limitation on the choice of material used in the waveguide 10 of the present invention. The material may be made of a material preferably selected from the group of dielectrics including ordinary or special glass or TiO2, or HfO2, or Ta2O5, or ZrO2, or AlN, or Al2O3, or ZnO, or SiO2, or Si3N4, or CaF2, or MgO, or combinations thereof. Said material may also be selected from substantially transparent polymers including polyethylene terephthalate (PET), polycarbonate (PC), polyethylene naphthalate (PEN), polymethyl methacrylate (PMMA), polyester, polyethylene (PE), polypropylene (PP), polyethylene furanoate, polymethyl methacrylate (PMMA), polymers based on poly(bis-cyclopentadiene) condensates, colorless polyimide (CP), cellulose, PEEK polymers, and combinations thereof. Composite materials based on polymers or polymer matrices have the advantage of being elastic and thus providing flexibility to the thin waveguide 10. The polymers or dielectrics may also contain additives such as chemicals or nanoparticles. Semiconductors such as Si and Ge or combinations thereof may also be chosen as materials for the waveguide 1, particularly where infrared light is used for illumination and imaging. The wide range of possible materials allows designing a variety of waveguides 10 of different lengths that may be suitable for guiding light in the UV, visible and infrared ranges of the electromagnetic spectrum. The waveguides 10 of the present invention may be at least partially doped waveguides 10 and may be configured as gradient index and / or step index waveguides 10. The waveguides 10 may include cladding layers and may include protective layers.

[0067] Advantageously, the waveguide 10 is made of a heat-resistant material, defined as a material capable of withstanding temperatures of up to 400° C. without alteration of its optical properties. In a variant, the waveguide 10 may be a free-standing waveguide 10 or a waveguide 10 realized on a substrate that does not necessarily have an optical function.

[0068] In a preferred embodiment, which will be described in more detail below, the waveguides are made of polysiloxane, which has stable optical properties up to 290°C.

[0069] Other good candidates for the material of the waveguide 10 in the present invention are polyimides and polyamideimides. These materials containing imide groups can withstand temperatures in excess of 300° C. while providing sufficient optical transmission, with typical losses of 0.2 dB / cm or less, which is generally sufficient for lengths of waveguide 20 that are typically centimeter-sized, e.g., 1-5 cm or 5-10 cm.

[0070] Aromatic polyamideimide polymers (PAI) are particularly interesting thermoplastics for realizing the waveguide 10 according to the invention, because they are optically transparent, offer high thermal stability even above 300° C., have excellent chemical resistance and robust mechanical properties so that they can be easily twisted and / or applied near the heater 3 or any hot spot in the device 2. Furthermore, aromatic polyamideimide polymers offer low losses of the order of 0.2-0.3 db / cm at a wavelength of 830 nm, which means that there is virtually no loss in intensity after a propagation length of 20-50 mm. It is possible to realize waveguides with sidewalls with roughness of the order of 1 / 10 of the wavelength in the visible region of the spectrum.

[0071] Although flexible waveguide 10 offers great advantages in limited spaces, the waveguide can also be made of rigid transparent materials that can be mechanically formed or etched or molded, such as sol-gel or any amorphous transparent material in the selected spectral band of transmission through the waveguide. Because the waveguide 10 in this application has a short length L, typically less than 20 cm, or less than 10 cm, or even less than 50 mm, the transmission characteristics are not as important and intensity losses of, for example, a factor of 2 or 3 can be easily utilized.

[0072] In an advantageous embodiment, the waveguide is a rigid or flexible hollow waveguide. Although hollow core fibers are usually known for higher absorption losses than solid fibers, which is detrimental to typical telecommunication applications, hollow core fibers are very suitable as waveguides in the present invention, and the total length of the waveguide is typically less than 10 mm, since the waveguide must fit into the aerosol generating device, where the available space is very limited. In fact, an intensity loss of more than 30% up to 50% over such a short length of hollow waveguide does not adversely affect the performance of the waveguide for the purpose of transmitting light reflected or refracted from the indicia on the aerosol generating device to a detector. A hollow core fiber that shows less than 10% intensity loss over 100 m makes it possible to guide light over distances typically shorter than 1 m with less than 10% loss, regardless of the wavelength of the guided light. Thus, light of a broad spectral distribution, such as UV light, visible light, and infrared light, can be guided simultaneously in a hollow core waveguide because the internal refractive index of the waveguide is substantially equal to 1 when the hollow core is a vacuum or a gas such as air.

[0073] In the context of the present invention, a hollow core waveguide may be a hollow core fiber having a cylindrical or non-cylindrical core with a smallest dimension of the core cross-section of at least 500 μm, preferably at least 50 μm, more preferably at least 5 μm.

[0074] It is understood that the hollow core waveguide need not be based entirely on a hollow core, but may include advantageous structures from inside the hollow core to the cladding walls. During manufacture of the hollow core waveguide, structures may be incorporated to improve light transmission.

[0075] In an embodiment, the capillary may be used to protect the waveguide, for example for thermal protection. In such a case, the waveguide 10 is placed in the central opening of the capillary tube. The capillary may contain at least two waveguides.

[0076] In a variant, the core and / or cladding of the waveguide may be composed of at least two layers. The mechanical and optical properties of the waveguide may be non-uniform along the length of the waveguide.

[0077] In an embodiment, the waveguide 10 may be formed directly on the surface of the heater 3, as long as it is made of a material that does not change its mechanical or optical properties up to 200° C., or 250° C., or 300° C. A synthetic diamond layer may be obtained, for example, on the outside or inside of the heater and configured as a waveguide.

[0078] In an embodiment, at least two different waveguides may be arranged, for example a solid SiO2 waveguide arranged in abutment with a polymer planar waveguide 10, the solid waveguide being arranged at a hot spot within the device 2 and the polymer planar waveguide 10 being arranged to transmit optical information on the indicia, such as an image, to a detector located away from the hot spot.

[0079] Input coupler 11 and output coupler 13 In an advantageous embodiment, at least a portion of the waveguide 10 is aligned with a resonant waveguide grating (RWG). Resonant waveguides are the preferred choice as input and output couplers. RWGs can be, for example: This is described in A. Sharon et al.: “Resonating grating-waveguide structures for visible and near-infrared radiation”: J. Opt. Soc. Am” vol. 14, nr. 11, pp. 2985-2993, 1997.

[0080] RWGs are fabricated using a multi-layer configuration, combining a sub-wavelength grating with a thin waveguide. When the incident light is diffracted by the grating and matched to the mode of the waveguide, resonance occurs. Since most of the spectrum of the input-coupled light does not couple into the waveguide, strong spectral effects are provided in reflection and / or transmission. This is due to the fact that the RWG is a corrugated waveguide and acts as a waveguide grating. By using the RWG in the indicia, it is possible to provide unique optical effects that are extremely difficult to identify and replicate. RWGs are generally designed to have a spatial periodicity that is shorter than the wavelength at which they operate, and are therefore called "sub-wavelength" structures or devices. Finally, RWGs have a periodicity that is close to, and a little higher than, the wavelength at which they operate. Very often, the period is significantly smaller than, for example, one-third of, the free space wavelength at which they normally operate. Because the periodicity of the RWG is small, the RWG does not allow for various diffraction orders, which distinguishes it from the much simpler diffractive optical element (DOE) shown in Figures 20-22.

[0081] The use of RWGs makes it possible to provide unique in-coupling and out-coupling optical effects, for example by providing high in-coupling and / or out-coupling efficiency, or to in-coupling and out-coupling polarized beams more efficiently or at a predefined angle that is not possible using normal gratings such as binary gratings. RWGs can be realized by embossing techniques that make it possible to provide inexpensive waveguides with very efficient light coupling efficiency, which may depend on the design, in particular on a particular predefined wavelength. In a variant not shown, at least one of the sides of the waveguide 10 is arranged as an in-coupling surface 12 and / or an out-coupling surface 14, either continuously or discontinuously, over at least 50% of the total length of the waveguide 10. Said in-coupling surface 12 and / or out-coupling surface 14 may be configured as an RWG.

[0082] Other preferred options for the input coupler 11 and the output coupler 13 include, but are not limited to, the following: Binary diffraction grating (Figure 20); Slanted grating; Multi-stage diffractive structure (Figure 21); blazed grating structure (Figure 22); Refractive and / or reflective microprisms; holograms such as volume holographic layers, e.g. photopolymer holograms; embedded microarrays; Surface relief gratings; Meta surface.

[0083] Binary and multi-step diffraction structures are shown in Fig. 20, Fig. 21 and Fig. 22. The diffraction structures show a pitch Δ that is selected as a function of the wavelength used. The binary structure allows diffracted light to be guided in at least two diffraction orders. Fig. 20 shows a two-step diffraction grating that allows light to be coupled in two directions in a waveguide. By using a multi-step approach, the diffraction efficiency is high in one direction (e.g. in the m=-1 order) and if an 8-step diffraction grating is formed, its performance is that of a blazed diffraction grating as shown in Fig. 22. Such diffraction grating structures can be formed by different processes such as hot embossing or photolithography and replication. The diffraction structures can be designed to realize optical functions that require complex optical components. For example, the diffraction structures can be designed to deflect and focus a light beam while coupling it into a waveguide, which is particularly useful for efficiently coupling light into a planar waveguide. Diffractive structures may be placed along the waveguide to modify the shape and aperture of the guided light beam, or may be used to in-couple, guide, and out-couple only TE or TM polarized light, which is particularly useful for detecting indicia that are difficult to replicate and whose optical effects are based on the use of polarization. In a variation, the waveguide may include a diffraction grating on its surface to out-couple a portion of the guided light beam 100, for example, for intensity referencing purposes, or possibly to illuminate and / or detect a second indicia.

[0084] Although refractive and reflective microprisms are the simplest way to realize input and output couplers and can be realized using the same molds as those used to make the waveguide 10, the refractive and reflective microprisms present a waveguide with protruding or edged surfaces for input and / or output coupling, rather than a surface structure. The use of metasurfaces as input and / or output coupling structures 11, 13 has several specific advantages. Metasurfaces can be constructed to provide true achromatic behavior at very thin surfaces by using only binary nanostructures. True achromatic input and / or output coupling allows to provide a solution where spectrally broadband optical information is provided by the indicia 4. Fabricating binary nanostructures is easier than fabricating complex analog surface relief diffractions, and it is also easier to replicate binary nanostructures, for example using nanoimprint lithography or soft lithography. Metasurfaces can be generated on the waveguide substrate or on a layer above the waveguide 10, for example by imprinting directly on a high refractive index inorganic layer, or by a resist lift-off process.

[0085] FIG. 4 shows an embodiment in which the light provided by the indicia 4 is in-coupled by an in-coupling element 20, which may be any light focusing element such as a lens. The light focusing element 20 may be a curved mirror, as shown in the embodiment of FIG. 8. Said lens or mirror may have a cylindrical shape. The in-coupling 20 and out-coupling optical elements may include different or several optical elements. The illumination of the indicia 4 may be provided by a different type of light source 40, preferably a broadband inexpensive light source 40 such as a white LED. The light source 40 may also be a VCSEL or a VCSEL array, or any other type of semiconductor laser, for example a visible or infrared semiconductor laser. In an embodiment, the light source 40 may include different types of light sources or light sources with different radiation intensities and / or radiation beam shapes and / or radiation light beam directions. In a variant, the light source used to illuminate the indicia 4 may be infrared light emitted by the heater 3 in operation.

[0086] In an embodiment, the light source may be a pulsed light source so that low levels of light intensity can be detected. The optical reading system may include a feedback electronic system, for example a synchronous detection system such as a lock-in amplifier that allows the detector to detect extremely low intensity signals, which can be used to reduce the power consumption of the device 2. The reflected and / or diffracted light beam 102 is coupled in and guided by the waveguide 10 and is at least partially detected by the detector 30. The detector 30 may be a single detector or a detector array, or may be a miniature camera. In an embodiment, the detector 30 is arranged to detect the spectrum or color distribution of the light provided by the illuminated indicia 4 and convert the optical information into electrical signals and data containing information about the article. In a variation of all the embodiments described herein, the detector 30 may be a detector system including processing electronics and / or a CPU for processing and converting data so that the aerosol generating device can identify the smoking article and / or adapt the parameters, for example the required temperature range or maximum temperature related usage parameters, for the smoking article.

[0087] Arrangement of Waveguide 10 and Device 2 For clarity of illustration, not all components are shown in all figures, for example only Figures 12, 14, 16 and 17 show the control unit 250, and only Figures 14, 17 and 18 show the cavity 2a of the device 2.

[0088] FIG. 4 and further FIGS. 5-16 illustrate alternative arrangements of the waveguide in the aerosol generating device that are compatible with the system of the present invention. The indicia 4 on the outer surface of the aerosol product 1, such as the heated non-burning stick 1, can be placed near a hot surface in the aerosol generating device 2. By using the waveguide system of the present invention, the detector 30 can be placed away from the hot surface, thereby avoiding heating the detector 30. In all embodiment variations of the present invention, where the in-coupling surface 12 or the in-coupler 11 of the waveguide 10 is placed near a hot surface, the waveguide 10 must be made of a heat-resistant material. There is no particular limit to the length or any dimension of the waveguide 10. The length L is defined as the dimension of the waveguide measured from the in-coupling surface to the out-coupling surface of the waveguide along the propagation direction of the light in the waveguide. For example, the waveguide 10 can be a short waveguide with a distance, defined as the length L, between 5 mm and 30 mm from the in-coupling surface 12 to the out-coupling surface 14. Said length L may be greater than 30 mm. The waveguide 10 is preferably longer than its width, but may be as large as its width. The width may also be greater than the length L. The waveguide may have a square shape, with an in-coupling surface located at one corner and an out-coupling surface located at another corner. The waveguide 10 may have at least two in-couplers and / or at least two out-couplers, which may be used in an arrangement of the waveguide 10 curved around a surface on the wrapping paper to detect indicia located at different places on the wrapping paper and at two different cross sections of the article. In an embodiment, the waveguide 10 may have a Y-shape with an in-coupling branch and at least two out-coupling branches. In a variant, the waveguide 10 may have a cross shape. In an embodiment, light may be in-coupled and / or out-coupled from any surface portion of the waveguide 10, for example from a portion of a thin wall 10'''. This is mainly interesting for intensity or polarization detection. In the case of transmission of the image of the indicium 4, the input and output couplers are preferably arranged in the plane of the waveguide 10, ie perpendicular to the thin wall 10''' of the waveguide 10.

[0089] Figure 5 shows a configuration of a waveguide system where the in-coupling surface 12 faces the indicium 4 and is configured to collect light provided by the indicium 4 without the use of an in-coupling element. Figure 2 shows a waveguide system where a detector system including a detector 30 is positioned on a different side of the article 1 than the side where the in-coupling surface 12 of the waveguide 10 is positioned.

[0090] FIG. 6 shows a cross-sectional view of a planar optical waveguide 10 including an integrated in-coupling and imaging lens 20. Such a lens 20 can be a refractive lens or a diffractive optical structure configured to have a focusing function. The waveguide 10 is configured to transmit an image of at least a part of the indicia 4 to a detector 30. In the embodiment of FIG. 6, an expanded waveguide system is shown, in which said part has a maximum width W1 and is projected on the out-coupling face 14 of the waveguide 10 as an image 120 having a maximum width W2 of a magnification F larger than the width W1 of said part. In a variant, said magnification F may be at least 2, preferably larger than 5 and even more preferably larger than 10. If the optical element 20 is integrated in the waveguide 10 on ot, the local thickness t3 may be larger or smaller than the thickness t1 of the waveguide cross section. In a variant, the integrated optical element 20 shown in FIG. 6 may be placed in an opening provided in the heater or on a mechanical element that is part of the heater 3.

[0091] The waveguide 10 of the present invention may have a typical maximum thickness t1 between 0.3 mm and 0.5 mm, more preferably between 0.5 mm and 2 mm. The waveguide of the present invention may be a non-uniform waveguide, for example a tapered waveguide 10. In some embodiments, the waveguide 10 may be thicker than 2 mm. The integrated focusing element may have a typical thickness t2 between 0.05 mm and 1 mm. The waveguide 10 may include an integrated focusing projection focusing element, not shown, at its output face 14. The integrated focusing projection focusing element may have a similar shape and geometry as the integrated focusing element 20.

[0092] In an embodiment, the waveguide 10 (optical fiber or planar waveguide) may have a core layer and a cladding layer, the core layer having a higher refractive index than one of the cladding layers. In a variant, a dielectric or metal layer may be disposed on at least one side of the waveguide 20.

[0093] FIG. 7 shows a schematic diagram of a manufactured aerosol generating device according to an embodiment of the present invention, showing a consumable inserted into the device. In this embodiment, the waveguide is arranged in a spiral configuration. In a variation of the embodiment of FIG. 7, the waveguide 10 may have multiple in-coupling surfaces and / or multiple out-coupling surfaces. By providing multiple in-coupling and out-coupling surfaces, it is possible to realize an arrangement of a waveguide system that can focus the light provided by multiple indicia arranged on a smoking article. For example, in a variation of the embodiment of FIG. 7, not shown, the waveguide 10 may include an array of indicia 4, so that each in-coupling surface 12 faces at least a part of the indicia 4 of the array. This allows the indicia 4 to be detected regardless of the axial orientation of the aerosol product product having such indicia after insertion into the cavity 2a.

[0094] FIG. 8 shows an embodiment in which the indicia 4 is placed at the tip of the smoking article 1 and is illuminated by a light beam 400 provided by an LED 4. The wide-angle light beam 400 illuminates the indicia 4 placed around the entire circumference of the article 4 during operation. This makes it possible to provide a solution that is independent of the axial orientation of the smoking article 1 relative to the fixed waveguide system of the device 2. FIG. 8 shows an embodiment in which the reflected light provided by the indicia 4 is directed to a concave mirror 202 that allows the light to be deflected and focused on the in-coupling surface 12 of the waveguide 10. The in-coupled light is guided by the waveguide and directed to a detector 30 or detector system located on another side of the device 2. The curvature of the waveguide 10 shown in FIG. 8 and in all embodiments herein is merely an exemplary configuration.

[0095] 9 shows an embodiment in which the indicia are arranged all around the smoking article 10 and the waveguide 10 is arranged such that the in-coupling surface 12 always faces at least a part of the indicia 4. This embodiment provides a solution that makes the detected light signal independent of the axial orientation of the article 1.

[0096] Figure 10 shows another embodiment in which the waveguide 10 is arranged such that the indicia 4 are arranged around the entire circumference of the smoking article 10 and the in-coupling surface 12 always faces at least a part of the indicia 4. This embodiment provides a solution that makes the detected optical signal independent of the axial orientation of the article 1. Figure 10 shows an example of a waveguide 10, preferably a planar waveguide, that transmits the spectral information of the indicia to the detector 30. In a variant, a flat cable containing multiple multimode fibres can be used.

[0097] 11 shows an embodiment in which an illumination part 13' of the waveguide 10 is adapted to guide the light 400 provided by the light source. Another part 11 is adapted to collect and guide the light 100 provided by the indicia 4. In an advantageous variant, said illumination part 10' can be another waveguide, such as a multimode fiber, arranged in a planar optical waveguide 10'.

[0098] 12 shows a variant in which at least two waveguides 10, 10' are arranged in the aerosol generating device 2. Each of said waveguides 10, 10' may be arranged at a different indicia 4, 4' and optical information may be provided to at least two separate detectors 30, 30' or detector systems. The at least two separate detectors 30, 30' or detector systems may be different and at least one of these detectors 30, 30' or detector systems may include an optical filter and / or a miniature spectrometer and / or a miniature camera.

[0099] 13 shows an embodiment in which the indicium 4 includes a layer whose reflected color or spectrum is modified by at least one absorbing or diffractive layer. A broadband light source 40, such as a white LED, directs a light beam 400 having a broad spectrum to the indicium 4. A waveguide 10 is positioned to transmit the reflected spectrum of the indicium 4 to a spectrometer 50 located away from the indicium 4.

[0100] It will be appreciated that the waveguides 10 of the present invention may be arranged in a wide variety of forms and geometries or may be arranged in any configuration within the aerosol generation device 2. Figure 14 shows a typical configuration in which at least one waveguide 10 is arranged such that a detector 30 or spectrometer 50 may be located in a region 2'' separated from the cavity 112 by a wall 2' or any other structure of the aerosol generation device 2. Figure 15 shows an exemplary configuration including at least two separate waveguides 10, 10'.

[0101] 15 and 16 show another embodiment illustrating the use of a waveguide 10 in an aerosol generating device.

[0102] The invention also relates to a method for authenticating a consumable product 1, comprising: Providing an aerosol generating device 2 as described and a consumable 1 as described, the consumable 1 including indicia disposed on an exterior surface thereof; Inserting at least a portion of the consumable 1 including the indicia 4 into the cavity 112 of the aerosol generation device 2; - illuminating indicia 4 on the outer surface of the consumable 1, collecting reflected light from the indicia 4 by a waveguide 10 and directing said reflected light to detectors 30, 50 of an optical reading system; authenticating the aerosol product 1 by calculating the information contained in the reflected light impinging on a detector 30 in the control unit; Includes.

[0103] In an embodiment, detector 30 is a detector system and may be or include a spectrometer 50 .

[0104] In one embodiment, the method further comprises the step of commanding the heater using the control unit based on the information calculated in the authenticating step.

[0105] Exemplary implementations (Examples 1 and 2) Example 1: Freestanding Waveguide 10 17-19 show an exemplary implementation of an apparatus 2 including a heater 3 for heating an article 1. A free-standing waveguide 10 is placed behind the tubular heater 3, which can reach temperatures of at least 250° C. and up to about 300° C.-350° C. A free-standing waveguide is defined as a waveguide that can be handled and positioned in the apparatus, for example by gluing or welding or mechanically fastening at least a portion of the waveguide, as opposed to a deposited waveguide, as described in the second implementation example below.

[0106] Said tubular heater 3 may be formed of an electrically conductive and / or heat conducting tube, such as a metal tube, defining an internal tubular cavity for receiving the aerosol product item 1. The tube may be electrically connected to the power supply and control unit of the aerosol generating device 2 so as to resistively heat the consumable item 1 when inserted. Alternatively, the tubular heater 3 may be contacted with resistive electrical means, such as resistive wires and tracks arranged on a flexible support material wrapped around the tube and connected to the power supply of the device 2. To avoid convective heating to the exterior of the device 2, an insulation assembly, not shown in the figures for clarity, may be provided around the heater 3 within the housing to keep the exterior temperature of the housing compatible with hand holding of the device (typically up to 30°C to 50°C).

[0107] The waveguide 10 includes an input coupler 11 and an output coupler 13. The input coupler 11 is configured to couple in the light provided by the indicium 4 and provides a guided light beam 100 that propagates to an end where the output coupler couples out at least a portion of the guided light beam 100. The input coupler 11 and the output coupler 13 in an exemplary implementation are diffraction gratings. The outcoupled light is directed to a detector 30, which may be a CMOS imager for imaging. The output coupler may have a circular or rectangular shape, with an output coupler width 13a and an output coupler length 13b that are selected, for example, as a function of the size of the guided light beam cross section at the level of the output coupler 13. The output coupler 13 and / or the input coupler 11 may be configured to focus in one plane, similar to a cylindrical lens, or in two orthogonal planes, similar to a symmetric lens. In a variant, the output coupler 13 may be configured to direct the light in two different directions and to at least two separate detectors.

[0108] In a device 2 such as the type of the exemplary implementation of FIG. 17, very limited space is available for placing optics, such as magnifying optics, within the housing, with optical access to the aerosol product 1 when inserted into the cavity 2a for reading the indicia 4 printed on the outer surface of the aerosol product 1. In particular, the internal space is typically less than 30 mm. 3 In some embodiments, the confined space is confined to a small volume having a length of less than 1×2 or 1×3 or 2×2 or 2×3 or 2×4 mm and a cross section of 1×2 or 1×3 or 2×2 or 2×3 or 2×4 mm. In variations, the confined space may have a different shape and a non-rectangular cross section.

[0109] The exemplary waveguide 10 has a substantially rectangular cross-section and has a thin wall having a small height t1 and a large width t2. Typical dimensions t1×t2 are 1 mm×3 mm, 1 mm×5 mm, or for example 2 mm×6 mm, or 0.5 mm×3 mm or 0.1 mm×2 mm or 50 μm×3 mm. The height t1 of the waveguide 101 may be less than 50 μm. The waveguide 10 is preferably made of a heat-resistant polymer such as polyimide, Kapton, or polyimide amide that can withstand temperatures higher than 100°C, preferably higher than 200°C. Such a high-temperature resistant waveguide allows the waveguide 10 to contact or be typically less than 0.5 mm close to the heater 3. The input coupler 11 is shown in FIG. 18 as the enlarged portion I of FIG. 17. The input coupler 11 is preferably a focusing and deflecting diffraction structure 11 that enables light, and thus at least a part of the image of the mark, to be input-coupled into the waveguide. The focusing input coupler 11 has a focal length selected such that an image is formed directly at the end of the waveguide 10. Since the waveguide 10 has a thickness smaller than its width (i.e., t1 < t2), total internal reflection can occur only between the larger sides 10', 10'' of the waveguide 10 depending on the aperture angle of the guided light beam 100. In a variant, at least one dielectric coating or absorptive coating may be applied to the thin wall. In a variant, the input coupler 11 and / or the output coupler 13 may provide focusing only in the vertical plane.

[0110] FIG. 19 shows the output coupling portion O of the system of FIG. 17. The output coupler 13 can be a rectangular-sized output coupler 13 having lateral dimensions 13a, 13b. The lateral dimensions 13a, 13b can typically be 1 mm×3 mm, 1 mm×3 mm, 2 mm×3 mm, 3 mm×3 mm, 3 mm×4 mm.

[0111] Providing a magnifying optic in such a thin space is not possible unless the magnifying optic is extremely small, i.e., less than 1 mm, and such a magnifying optic cannot image macroscopically sized coded indicia, such as indicia made with a bar code 0.2-0.5 mm wide. As shown in the enlarged view of Figure 18, the use of flexible waveguides, as facilitated by the present invention, allows one or both ends of the waveguide 10 to be curved so that the input coupler 11 and / or output coupler 13 are placed in a predetermined position, such as alignment of the input coupler 11 parallel to or in contact with the wall 2a' or with the opening of the cavity 2a.

[0112] To withstand high temperatures, the waveguide 10 is preferably made of a highly curable polysiloxane, which makes it possible to obtain low optical losses of less than 0.02 db / cm at 850 nm. Polysiloxane waveguides are highly flexible and have stable optical properties up to 290° C., where the loss is typically less than 0.6 dB / cm. An alternative that will be described is the use of polyamide-imide polymers to manufacture the waveguide 10.

[0113] In a variant, a heater 3 etched over a length to provide a channel and made of a heat resistant material such as Al2O2 fused silicon or glass or sol-gel, or any of the heat resistant polymers described herein, can be fixed within the channel and used as a waveguide 10 to transfer optical information from one side of the heater to the other side of the heater.

[0114] Example 2: Deposited Waveguide 10 In another exemplary implementation, not shown, the waveguide 10 can be deposited on a surface of an element of the device by a suitable deposition process. For example, the waveguide 10 can be printed by inkjet printing into a ring that at least partially surrounds a portion of the cavity. In another example, the heater 3 can include a deposited waveguide 10. The waveguide 10 can be deposited, for example, over the etched length of the heater 3 or over the etched length of any component of the device 2.

Claims

1. 1. An aerosol generating system comprising: an aerosol product article (1) extending along a longitudinal axis, the aerosol product article (1) including at least one indicia (4) arranged on a surface of the aerosol product article (1) that includes information relating to the aerosol product article (1); An aerosol generating device (2), a cavity (2a) having an opening adapted to receive said aerosol product (1); a heater (3) arranged around the cavity (2a) for heating the aerosol product (1) after its insertion into the cavity (2a); an optical reading system including at least one photodetector (30); A power supply unit; a control unit (250) configured to control at least the heater and the optical reading system; An aerosol generating device (2), Including, the optical reading system is configured to illuminate the indicia in the cavity (2a) with a light beam and includes at least one waveguide (10) including an in-coupling surface (12) and an out-coupling surface (14), the waveguide (10) being configured to transmit at least a reflected light beam from the indicia (4) to the out-coupling surface (14) for out-coupling the reflected light beam to the at least one detector (30); Aerosol generation systems.

2. The aerosol generation system according to claim 1 , wherein an in-coupling structure (11) is arranged on the in-coupling surface (12).

3. The aerosol generation system according to claim 2 , wherein an output coupling structure (13) is arranged on the output coupling surface (14).

4. The aerosol generation system of claim 3, wherein at least a portion of the input coupling structure (11) and / or the output coupling structure (13) is selected from a diffractive structure, a flat or curved wedge portion of the waveguide (10), an array of microprisms, a holographic layer, a metasurface, an electrostatically addressable micromirror or microshutter array, a lens, and a mirror.

5. The aerosol generation system of claim 4, wherein the input coupling structure (11) and / or the output coupling structure (13) are configured to focus and / or deflect a light beam incident on the input coupling structure (11) and / or the output coupling structure (13).

6. An aerosol generation system as described in any one of claims 3 to 5, wherein the input coupling structure (11) and / or the output coupling structure (13) are achromatic structures providing the same input coupling, output coupling efficiency and / or focusing, respectively, in a spectral band of at least 50 nm.

7. The aerosol generation system according to any one of claims 3 to 6, wherein the input coupling structure (11) and / or the output coupling structure (13) have a focal length greater than or equal to the length L of the waveguide (10).

8. The aerosol generation system of claim 7, wherein the input coupling structure (11) and / or the output coupling structure (13) have a focal length shorter than the length L of the waveguide (10), a focusing structure is arranged on at least one side of the waveguide, and the focusing structure is configured as a relay structure for transmitting an image from at least a portion of the indicia (4) to the output coupling surface (14) or outside the waveguide (10) at a certain distance (d) from the output coupling surface (14).

9. The aerosol generation system according to any one of claims 1 to 8, wherein the waveguide (10) is an optical fiber or an optical fiber bundle.

10. The aerosol generation system according to any one of claims 1 to 9, wherein the waveguide (10) is a planar optical waveguide.

11. The aerosol generation system according to claim 10, wherein the waveguide (10) is a flexible waveguide.

12. The aerosol generating system according to any one of the preceding claims, wherein the waveguide (10) is at least partially made of polysiloxane.

13. The aerosol generating system according to any one of claims 1 to 11, wherein the waveguide (10) is at least partially made of a polymer containing imide groups.

14. 14. The aerosol generating system according to claim 13, wherein the waveguide (10) is at least partially made of polyamideimide or polyimide.

15. The aerosol generation system according to any one of claims 1 to 14, wherein an optical focusing element (20) is arranged between the cavity (2a) and the in-coupling surface (12).

16. The aerosol generation system of claim 15, wherein the optical focusing element (20) is monolithically integrated within or on the waveguide (10).

17. An aerosol generation system as described in any one of claims 1 to 16, wherein the waveguide (10) is positioned to transmit a magnified image of at least a portion of the indicia (4) to the output coupling surface (14) or outside the waveguide (10).

18. The aerosol generation system according to any one of claims 1 to 17, wherein the waveguide (10) is at least partially wrapped around a length of the cavity (2a).

19. An aerosol generation system according to any one of claims 1 to 18, wherein at least a portion of the waveguide (10) is configured to transmit light provided by an emitter to the indicia (4).

20. The aerosol generation system according to any one of the preceding claims, wherein at least a part of the waveguide (10) is realised on at least one of the surfaces of the heater (3).

21. The aerosol generation system according to any one of claims 1 to 20, wherein the detector (30) is a detector array.

22. An aerosol generation system according to any one of claims 1 to 21, wherein at least one optical filter (F) is arranged between the output coupling surface (14) and the detector (30).

23. The aerosol generation system according to any one of claims 1 to 21, wherein an optical spectrometer (50) is disposed between the output coupling surface (14) and the detector (30).

24. The aerosol generation system according to any one of claims 1 to 23, wherein the detector (30) includes an image processing device.

25. A method for authenticating an aerosol product (1) using an aerosol generating system according to any one of claims 1 to 24, comprising the steps of: inserting at least a portion of the aerosol production article including the indicia into the cavity (2a) of the aerosol generating device (2); illuminating the indicia on an exterior surface of the aerosol product article, collecting reflected light from the indicia with the waveguide, and directing the reflected light to the detector of the optical reading system; authenticating the aerosol product (1) by calculating the information contained in the reflected light impinging on the detector (30) in the control unit; A method comprising:

26. 26. The method of claim 25, further comprising the step of instructing the heater (3) using a control unit (250) based on the information calculated in the authentication step.

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