WO2024047017A1

WO2024047017A1 - Aerosol generating system including a multi-chromatic light-emitting diode and a beam splitter

Info

Publication number: WO2024047017A1
Application number: PCT/EP2023/073623
Authority: WO
Inventors: Pier Paolo MONTICONE; Layth Sliman BOUCHUIGUIR
Original assignee: Jt International Sa
Priority date: 2022-09-01
Filing date: 2023-08-29
Publication date: 2024-03-07

Abstract

An aerosol generating system (102) includes a case (104) defining an air flow path (110) in order to generate an aerosol to be inhaled by a user, the case (104) including a first light output area (116), a light-emitting device (132) arranged inside the case (104) and capable of generating light to be displayed on the first light output area (116), the light-emitting device (132) including a multi-chromatic light-emitting diode (140). The case (104) comprises a second light output area (120), the aerosol generating system (102) further comprising a first beam splitter (142) between the light-emitting device (102) and the first light output area (116), the first beam splitter (142) being able to divert a part of light emitted by the light-emitting device (132) to the second light output area (120).

Description

AEROSOL GENERATING SYSTEM INCLUDING A MULTI -CHROMATIC LIGHTEMITTING DIODE AND A BEAM SPLITTER

Technical field

The present invention relates to an aerosol generating system comprising a case and a light-emitting device. More particularly, the present invention relates to such aerosol generating systems including two light output areas, the light-emitting device including a multi-chromatic lightemitting diode, and the system including a beam splitter. The present invention also relates to a method of controlling such an aerosol generating system.

Background

Referring to Fig. 1, a conventional aerosol generating system 2 includes a case 4 defining an air flow path in order to generate an aerosol to be inhaled by a user. In the example of Fig. 1, the case 4 includes an oven cavity for receiving a tobacco stick 6. When the tobacco stick 6 is received in the oven cavity defined by the case 4, the tobacco stick 6 may form a mouthpiece of the aerosol generating system 2 and an air outlet of the air flow path defined by the case 4. As visible in Figs. 1 and 2, the case 4 includes a light output area 8. In the present case, the light output area is provided on a front wall of the case 4. Inside the case 4, as depicted on the left of Fig. 2, the aerosol generating system includes a printed circuit board 10 including a circuitry 12 and a plurality, e.g. 8, LEDs 14, 16, 18, 20, 22, 24, 26 and 28. As visible in Fig. 2, the LEDs 14 to 28 are vertically aligned in order to face the light output area 8.

By virtue of this arrangement, the light output area 8 may form a lightbar including an illuminated portion 30 and a nonilluminated portion 32. By controlling an on/off state of the LEDs 14 to 28 , it is possible to control a length of the lightbar formed on the light output area 8 , in order to show, for example , a status of the aerosol generating system .

Although such a system is considered generally satis factory and is very much appreciated by users , it involves a need to provide a plurality of light-emitting devices , e . g . 8 LEDs , in order to display a lightbar and provide the user with relevant information . This results in a higher complexity of the arrangement inside the case 4 , and in particular in a need for cables and additional mechanical constraints of putting the LED behind the opening forming the light output area . This results in making the system more expensive , more cumbersome and reduces the possibilities for user interface design .

Documents KR 2016/ 0112771 , WO 2019/ 115996 and WO 2021 /259949 show examples of devices in which light i s displayed by means of a light emitting element . But these documents do not provide a guidance as to how to make an aerosol generating system cheaper, smaller, and how to provide more possibilities for user interface design

There is therefore a need to further improve the integration of a light-emitting device and a light output area in an aerosol generating system . It is thus an obj ect of the present invention to provide such improved aerosol generating systems that can remedy the drawbacks of the conventional solutions .

Summary

The mentioned drawbacks are remedied by the subj ect-matter of the independent claims . Further preferred embodiments of the present invention are defined in the dependent claims .

According to one aspect of the present invention, there is provided an aerosol generating system including a lightemitting device arranged inside the case and capable of generating light to be displayed on the first light output area, the light-emitting device including a multi-chromatic light-emitting diode . The case comprises a second light output area, the aerosol generating system further comprising a first beam splitter in a light path between the light-emitting device and the first light output area, the first beam splitter being able to divert a part of light emitted by the light-emitting device to the second light output area .

In the invention according to the first aspect of the invention, it is provided an aerosol generating system having a plurality of light spots while reducing the need for multiple LEDs . This also reduces the need for cables and the number of mechanical constraints , which makes the aerosol generating system cheaper, smaller, and provides more possibilities for user interface design .

According to one embodiment , the multi-chromatic lightemitting diode is an RGB-AC quinti-chromatic light-emitting diode .

Such an embodiment provides the possibility of a plurality, e . g . five di f ferent signals to be sent to the user, without making it necessary to add a further light-emitting device .

Preferably, the multi-chromatic light-emitting diode is capable of emitting flashing light .

In another embodiment , the multi-chromatic light-emitting diode is capable of emitting pulsing light .

Such embodiments provide the possibility of increasing even more the number of di f ferent signals to be sent to the user without increasing a need for multiple light-emitting devices .

Preferably, the light-emitting device further includes an additional multi-chromatic light-emitting diode .

Since typical single light-emitting diodes are designed to emit at the same time up to four or five wavelengths , having two multi-chromatic light-emitting diodes allows increasing even more the number of di f ferent signals to be sent to the user, while keeping the number of light-emitting diodes reasonable .

Preferably, the first light output area and/or the second light output area includes a light di f fuser . In one embodiment , the system further includes an optical bandpass filter in a light path between the light-emitting device and at least one of the first light output area and the second light output area .

Such an embodiment allows , when combined with the at least one multi-chromatic light-emitting diode , addressing independently a plurality of light spots .

In an embodiment , the light-emitting device is configured to emit di f ferent colours at the same time .

In another embodiment , the light-emitting device is configured to switch through di f ferent colors , wherein the switching operation is performed at a frequency within 100 Hz and 10 kHz , preferably within 100 Hz and 1 kHz .

Such an embodiment allows having one single LED driver multiplexed through the di f ferent pins of the light emitting device , instead of one driver for each color .

Regarding the switching frequency, having a frequency higher than 100 Hz (Hertz ) allows avoiding perceivable flickering by the human eye .

In another embodiment , the system further includes a light guide in a light path between the light-emitting device and at least one of the first light output area and the second light area, and, preferably, a lens in a light path between the light-emitting device and the light guide .

Such a configuration allows addressing light spots provided at very di f ferent locations on the case .

In another embodiment , the case includes a USB socket , the multi-chromatic light-emitting diode being able to emit light of a first color, the first light output area including a first light di f fuser around the USB socket , and the aerosol generating system comprises a first optical bandpass filter having an optical passband corresponding to the first color, the first optical bandpass filter being in a first light path between the light-emitting device and the first light di f fuser .

In another embodiment , the case includes a sidewall having a side window, the multi-chromatic light-emitting diode being able to emit light of a second color, the second light output area including a second light di f fuser on the side window, and the aerosol generating system comprises a second optical bandpass filter having an optical passband corresponding to the second color, the second optical bandpass filter being in a second light path between the light-emitting device and the second light di f fuser .

Preferably, the multi-chromatic light-emitting diode is able to emit light of a third color, the optical passband of the second optical bandpass filter also corresponding to the third color .

In an embodiment , the case includes a third light output area arranged so that a part of light emitted by the light emitting device may be diverted to the third light output area .

Preferably, the case includes an oven cavity adapted to at least partially receive a tobacco stick, the oven cavity having an opening portion, the multi-chromatic light-emitting diode being able to emit light of a fourth color, the third light output area comprising a third light di f fuser forming a continuous circle and/or a circular array of dots around the opening portion, the aerosol generating system further including a third optical bandpass filter having an optical passband corresponding to the fourth color, the third optical bandpass filter being in a third light path between the lightemitting device and the third light di f fuser .

It is also possible to foresee a second beam splitter able to divert a part of light having passed the first beam splitter to the third light output area .

According to another aspect of the present invention, there is provided a method of controlling an aerosol generating system as set forth above , including a step of controlling the multi-chromatic light-emitting diode in order to display at least two distinct light signals on the first light output area and/or on the second light output area .

Brief description of drawings

Embodiments of the present invention, which are presented for better understanding of the inventive concepts and which are not to be seen as limiting the invention, will now be described with reference to the figures wherein :

Fig . 1 , which was already referred to in the introductory part , depicts a perspective view of an aerosol generating system according to the prior art ,

Fig . 2 , which was already referred to in the introductory part , is a detailed view of a light output area and a printed circuit board of the aerosol generating system of Fig . 1 ,

Fig . 3 depicts an aerosol generating system according to a first embodiment of the present invention,

Fig . 4 is a perspective , cross-sectional view of the case of the aerosol generating system of Fig . 3 ,

Fig . 5 is a schematic diagram showing the construction of the light-emitting device and the light output area in the aerosol generating system of Figs . 3 and 4 ,

Fig . 6 is a cross-sectional view of a case of an aerosol generating system according to a second embodiment of the present invention,

Fig . 7 is another cross-sectional view of the case of the aerosol generating system of Fig . 6 ,

Fig . 8 is a schematic diagram of a light-emitting device and a light path towards light output areas of the aerosol generating system of Figs . 6 and 7 ,

Fig . 9 is a schematic view of a l ight-emitting device and a portion of a light path towards light output areas (not visible in Fig . 9 ) of an aerosol generating system according to a third embodiment of the present invention, and

Fig . 10 is a table showing wavelength combinations between two light-emitting diodes of the light-emitting device of Fig . 9 .

Detailed description

Embodiments of the present invention will now be described with reference to the following figures . The same or sequentially similar numbers are used throughout the figures to reference like features and components . Referring now to Figs. 3 to 5, an aerosol generating system 102 includes a case 104 accommodating a battery 106 and a printed circuit board 108.

The case 104 defines an air flow path 110 between an air inlet 112 and an air outlet 114. By doing so, air flowing in the air flow path 110 may generate an aerosol which is provided to a user for inhalation via the air outlet 114.

The case 104 may include three light output areas 116, 118 and 120. As depicted in Figs. 3 and 4, the light output areas 116, 118 and 120 are provided on an outside wall of the case 4. By virtue of this arrangement, it is possible to send visual signals to a user of the aerosol generating system 102.

Each of the light output areas 116, 118 and 120 includes a respective light diffuser 122, 124 and 126.

The light diffusers 122, 124 and 126 may be formed by an optical diffusing material, a hole, a semi-transparent material, a half-mirror or a net.

The printed circuit board 108 includes a microcontroller 128, a light-emitting diode driver (LED driver) 130 and a light-emitting device 132. The microcontroller 128 is able to select a wavelength to be emitted by the light-emitting device 132. The printed circuit board 108, the microcontroller 128, the light-emitting device driver 130 and the light-emitting device 132 are arranged inside the case 104. The case 104 defines a first light path 134 connecting the light-emitting device 132 to the light output area 116, a second light path 136 connecting the lightemitting device 132 to the light output area 118, and a third light path 138 connecting the light-emitting device 132 to the light output area 120. By virtue of this arrangement, the light-emitting device 132 is capable of generating light to be displayed on the light output areas 116, 118 and 120.

The light-emitting device 132 is configured to switch through different colors with a switching operation. Such a switching operation may imply pulsing the light source at a high frequency, so as to intercalate different emitted wavelengths to achieve multiple light openings to be lighted simultaneously from a user point of view. The switching operation may be a time division multiplexing, also known under the acronym TDM. Alternatively, the light-emitting device 132 may be configured to emit different colors at the same time.

Such a switching operation may be performed at a frequency within 100 Hz and 10 kHz. In the depicted embodiment, the intensity is as well modulated by adjusting the ON time, for example by means of a pulse width modulation (PWM) adjustment, so that the switching frequency can be increased more easily to 10 kHz.

As visible in Fig. 4, the light-emitting device 132 includes a multi-chromatic light-emitting diode 140. The multi-chromatic light-emitting diode 140 is a light-emitting diode (LED) capable of emitting at least two different colors.

The multi-chromatic light-emitting diode 140 may be an RGB-AC quinti-chromatic light-emitting diode. This diode may emit five colors corresponding to five different wavelengths, including red color, green color, blue color, amber color and cyan color.

The multi-chromatic light-emitting diode 140 is capable of emitting flashing light and capable of emitting pulsing light.

The aerosol generating system 102 includes a beam splitter 142 (not visible in Fig. 3) . In the depicted embodiment, and as visible in Fig. 4, the beam splitter 142 is provided on a rectilinear line joining the light-emitting device 132 and the light output area 118. However, the beam splitter 142 may be provided at any location provided in a light path between the light-emitting device 132 and the light output area 116, 118 and 120.

As visible in Fig. 4, the beam splitter 142 is able to divert a part of the light emitted by the light-emitting device 132. More specifically, a part of the light emitted by the light-emitting device 132 towards the light output area 118 is diverted on the light path 138. The diverted part of light is diverted towards the light output area 120.

Referring back to Fig. 3, the light path 138 may include a light guide 144. The light guide 144 may guide a light along a line which is not necessarily rectilinear. Preferably, the light path 138 may include a lens 145 provided between the light-emitting device 132 and the light guide 144. By virtue of this arrangement, the light guide 144 is provided between the light-emitting device 132 and the light output area 120, and the light guide may concentrate light emitted by the light-emitting device 132, so that it is transmitted by the light guide 144.

The light guide 144 may be any components chosen among a plastic component, a mirror or an optical fiber.

The aerosol generating system 102 may include an optical bandpass filter 146 between the light-emitting device 132 and the light output area 120. More specifically, in the depicted embodiment, the optical bandpass filter 146 is provided between the light guide 144 and the light diffuser 126. However, the optical bandpass filter 146 may be provided at any location in the light path 138.

Although, in the depicted embodiment, only one beam splitter, light guide, lens, and optical bandpass filter have been disclosed, and referring to only the light path 136 and 138, it is possible to provide such components on any one of the light paths 134, 136 and 138 and/or provide additional beam splitters, lenses, light guides and optical bandpass filters .

By virtue of such an arrangement, and as depicted in Fig. 5, the aerosol generating system 102 may include a light source 148, a light path 150, an optical bandpass filter 146 and a user interface 152.

The light source 148 may include the light-emitting device 132 including the multi-chromatic light-emitting diode 140.

The light path 150 may include the light path 134, 136, 138, the beam splitter 142, the light guide 144 and the lens 145.

The user interface 152 may include the light output areas 116, 118, 120, the light diffusers 122, 124 and 126.

By virtue of this arrangement, it is possible to provide the user with a visual signal displayed on the user interface 152 using a light source 148 including only one light-emitting diode 140. More specifically, different visual signals corresponding respectively to different colors may be depicted using the multi-chromatic light-emitting diode 140. Also , when the multi-chromatic light-emitting diode 140 emits a light having a wavelength filtered by the optical bandpass filter 146 , it is possible to see a light displayed on the light output area 118 whereas no light is displayed on the light output area 120 . Conversely, when the light emitted by the multi-chromatic light-emitting diode 140 corresponds to the wavelength of an optical pass band of the optical bandpass filter 146 , a light is displayed on each of the light output areas 118 and 120 .

By doing so , it is possible to display a light bar on the case 104 using only one multi-chromatic light-emitting diode . It is also possible to individually address a plurality of light spots so as to , for example , display a light bar such as the one of the light output area 8 of the conventional aerosol generating system 2 without making it necessary to use more than one light emitting device .

Referring now to Figs . 6 to 8 , an aerosol generating system 202 according to a second embodiment of the present invention is depicted . More speci fically, Fig . 6 is a cross- sectional view of the case 104 of the aerosol generating system 202 according to the plane VI-VI shown on Fig . 7 , and Fig . 7 is a cross-sectional view of the case 104 of the aerosol generating system 202 along the plane VI I-VI I depicted on Fig . 6 . Fig . 8 , in which inter alia the case 104 is not depicted, is a schematic view of the optical components of the aerosol generating system 202 .

As visible in Fig . 6 , the case 104 of the aerosol generating system 202 includes a USB socket 204 . The USB socket 204 may receive a USB plug (not depicted) for charging the battery 106 of the aerosol generating system 202 , and/or for setting parameters of the aerosol generating system 202 .

The case 104 of the aerosol generating system 202 includes an oven cavity 206 . The oven cavity 206 is intended to receive a tobacco stick (not depicted) such as the tobacco stick 6 of the aerosol generating system 2 o f Figs . 1 and 2 . To that end, the oven cavity 206 may have a cylindrical shape with a circular cross section . At an upper side of the case 104 , the oven cavity 206 includes an opening portion 208 forming a circle . As visible in Fig. 7, the case 104 of the aerosol generating system 202 includes two side walls 210 and 211. The side walls 210 and 211 are opposed to each other. The side wall 210 includes a side window 212.

As well as in the first embodiment, the case 104 of the aerosol generating system 202 may define an air flow path in order to generate an aerosol to be inhaled by a user. The case 104 of the aerosol generating system 202 may also include a light output area 116 including the first light diffuser 122, a second light output area 118 including the second light diffuser 124, and a third light output area 120 including the third light diffuser 126. More specifically, in the second embodiment, the light diffuser 122 is around the USB socket 204, the light diffuser 124 forms a continuous circle around the opening portion 208 and the light diffuser 126 is on the side window 212.

As well as in the first embodiment, the aerosol generating system 202 includes a light-emitting device 132 arranged inside the casing 104 and capable of generating light to be displayed on the light output areas 116, 118 and 120. More specifically, the light-emitting device 132 includes a multi- chromatic light-emitting diode 140 (not depicted in Figs. 6 and 7) capable of emitting light of a first color, for example red, a second color, for example blue, a third color, for example green, and a fourth color, for example yellow.

As well as in the first embodiment, the aerosol generating system 202 includes a first beam splitter 142 between the light-emitting device 132 and the light output area 116. By virtue of this arrangement, the first beam splitter 142 is able to divert a part of the light emitted by the lightemitting device 132. The diverted part may be diverted to the light output area 118.

The aerosol generating system 202 includes a second beam splitter 214. As visible in Fig. 6, the beam splitter 214 is provided between the beam splitter 142 and the light output area 116. By virtue of this arrangement, the beam splitter 214 is able to divert a part of the light having passed the beam splitter 142. The diverted part may be diverted to the light output area 120. The aerosol generating system 202 includes three optical bandpass filters 216 , 218 and 220 . The optical bandpass filters 216 , 218 and 220 are respectively associated to the light paths 134 , 136 and 138 . That is , the optical bandpass filter 216 is provided between the second beam splitter 214 and the light di f fuser 122 , the optical bandpass filter 218 is provided between the second beam splitter 214 and the light di f fuser 124 , and possibly on the light guide 144 , and the optical bandpass filter 220 is provided between the first beam splitter 142 and the light di f fuser 126 . In other words , the optical bandpass filter 216 is in the light path 134 associated to the USB socket 204 , the optical bandpass filter 218 is in the light path 136 associated to the opening portion 208 of the oven cavity 206 , and the optical bandpass filter 220 is in the light path 138 associated to the side window 212 of the side wall 210 . In each case , the optical bandpass filter is arranged in the portion of the light path being downstream of the beam splitter which is closest to the light di f fuser .

The optical bandpass filter 216 has an optical pass band corresponding to the first color, being namely red . The optical bandpass filter 218 has an optical pass band corresponding to the fourth color, being namely yellow . The optical bandpass filter 220 has an optical pass band corresponding to both the second and third colors , being namely green and blue . In other words , only red light may pass through the optical bandpass filter 216 , only yellow light may pass through the optical bandpass filter 218 and only blue and green light may pass through the optical bandpass filter 220 .

As well as in the first embodiment , the multi-chromatic light-emitting diode 140 of the aerosol generating system 202 may emit flashing light and pulsing light .

By virtue of this arrangement , it is possible to control the light-emitting device 132 in order to send the following visual signals to the user :

- a red continuous light around the USB socket 204 to inform the user that the aerosol generating system 202 needs to have its battery recharged or reloaded and flashing when the state of charge is critical , - a yellow ring pulsing around the opening portion 208 of the oven cavity 206 when the aerosol generating system 202 is heating up and then being continuous when the oven cavity is suf ficiently hot , so that the aerosol generating system may be ready for vaping,

- a green light continuous on the side window 212 indicating that the aerosol generating system 202 is on, and

- a blue light on the side window 212 to inform the user that a cleaning cycle of the aerosol generating system 202 is ongoing .

In order to display a red light around the USB socket 204 , the multi-chromatic light-emitting diode 140 is controlled, so that it emits red light . The red beam emitted by the multi- chromatic light-emitting diode 140 passes through the beam splitters 142 and 214 , and reaches the optical bandpass filters 216 , 218 and 220 . The red beam is thus filtered by the optical bandpass filters 218 and 220 but may pass through the optical bandpass filter 216 . As a result , a continuous , flashing or pulsing red light may be displayed on the light di f fuser 122 and no light is displayed on the light di f fusers

124 and 126 . Similarly, in order to display a yellow ring around the opening portion 208 of the oven cavity 206 , the multi-chromatic light-emitting diode 140 is controlled so as to emit yellow light . The yellow beam emitted by the multi- chromatic light-emitting diode 140 passes through the beam splitters 142 and 214 and reaches the optical bandpass filters 216 , 218 and 220 . The yellow beam is filtered by the optical bandpass filters 216 and 220 but passes through the optical bandpass filter 218 . As a result , a yellow circle is displayed on the light di f fuser 124 and no light is displayed on the light di f fusers 122 and 126 . In order to display blue or green light on the side window 212 , blue light or green light is emitted by the multi-chromatic light-emitting diode 140 . The blue beam or the green beam passes through the beam splitters 142 and 214 and reaches the optical bandpass filters 216 , 218 and 220 . The blue beam or the green beam is then filtered by the optical bandpass filters 216 and 218 but passes through the optical bandpass filter 220 , so that a blue light or a green light is displayed on the light di f fuser 126 and no light is displayed on the light di f fusers 122 and 124 .

Referring now to Figs . 9 and 10 , it is depicted an aerosol generating system 302 according to a third embodiment of the present invention . The aerosol generating system 302 mainly di f fers from the aerosol generating systems 102 and 202 of the respective first and second embodiment by the light-emitting device 304 . For that reason, and for the sake of clarity of the figures , all components which are not optical components of the aerosol generating system 302 are omitted in Fig . 9 , and only the light-emitting device 304 , the beam splitter 142 and the portions of the light beams emitted by the lightemitting device 304 and located upstream or in vicinity of the beam splitter 142 are depicted in Fig . 9 .

The light-emitting device 304 of the aerosol generating system 302 di f fers from the light-emitting device 132 of the aerosol generating systems 102 and 202 mainly in that it includes an additional multi-chromatic light-emitting diode 306 . The additional multi-chromatic light-emitting diode 306 comes in addition to the multi-chromatic lightemitting diode 140 . The multi-chromatic light-emitting diodes 140 and 306 have di f ferent wavelengths selections .

By virtue of this arrangement , it is possible to provide the user with more than four or five di f ferent visual signals , without being required to use a light-emitting diode designed to emit more than four or five wavelengths . It is thus possible to improve the user' s experience at a reasonable cost .

More speci fically, the multi-chromatic light-emitting diode 140 is able to emit light of at least one wavelength among a first group of wavelengths . For example , the first group of wavelengths may include the wavelength 455 nm, 530 nm, 590 nm and 625 nm . The multi-chromatic light-emitting diode 306 is able to emit light of at least one wavelength among a second group of wavelengths . For example , the second group of wavelengths includes 420 nm, 505 nm, 530 nm and 617 nm .

That is , in the third embodiment , for any wavelength taken among the first wavelength group and any wavelength taken among the second wavelength group, a di f ference between the two wavelengths is more than a predetermined threshold, the threshold being preferably between 20 nm and 30 nm .

Referring now to Fig . 10 , it is shown a table wherein di f ferent wavelength combinations are indicated for the respective multi-chromatic light-emitting diodes 140 and 306 .

Namely, in each of the cells 308 being on the top line , di f ferent wavelengths of the multi-chromatic light-emitting diode 140 are indicated . Similarly, in cells 310 on the left column, wavelengths for the multi-chromatic light-emitting diode 306 are indicated .

Other cells of the table of Fig . 10 may include noncombining cells 312 , which correspond to wavelength combinations in which the wavelength of the first group and the wavelength of the second group are too close to each other . The table of Fig . 10 may include combining cells 314 , hatched in Fig . 10 , which correspond to a combination in which the wavelength of the first group of wavelengths is too far away from the wavelength of the second group of wavelengths , in order to provide an ef ficient repartition of the wavelengths in the group . The table of Fig . 10 may include preferable cells 316 , shown blank in Fig . 10 , and which correspond to a combination of wavelengths in which the choice of the wavelength of the first group and the choice of the wavelength of the second group are optimal .

In order to choose wavelength combinations , the wavelengths of the first group are firstly identi fied . Then, non-combining cells 312 , combining cells 314 and preferable cells 316 corresponding to the wavelengths of the first group are identi fied . Then, wavelengths of the second group are chosen in such a way that they do not correspond to noncombining cells 312 , and i f possible , so that they correspond to preferable cells 316 which were identi fied in the previous step . By doing so , it is possible to choose wavelength combinations which may be filtered, transmitted and identi fied by the user in an optimal manner .

Although all detailed embodiments have been described, these only serve to provide a better understanding of the invention defined by the independent claims and are not to be seen as limiting .

Claims

1. An aerosol generating system (102, 202, 302) including : a case (104) defining an air flow path (110) in order to generate an aerosol to be inhaled by a user, the case (104) including a first light output area (116) , a light-emitting device (132) arranged inside the case (104) and capable of generating light to be displayed on the first light output area (116) , the light-emitting device (132) including a multi- chromatic light-emitting diode (140) , characterized in that the case (104) comprises a second light output area (120) , the aerosol generating system (102, 202, 302) further comprising a first beam splitter (142) between the light-emitting device (102, 202, 302) and the first light output area (116) , the first beam splitter (142) being able to divert a part of light emitted by the lightemitting device (132) to the second light output area (120) .

2. The aerosol generating system (102, 202, 302) according to claim 1, wherein the multi-chromatic lightemitting diode (140) is an RGB-AC quinti-chromatic lightemitting diode.

3. The aerosol generating system (102, 202, 302) according to claim 1 or 2, wherein the multi-chromatic lightemitting diode (140) is capable of emitting flashing light.

4. The aerosol generating system (102, 202, 302) according to any one of claims 1 to 3, wherein the multi- chromatic light-emitting diode (140) is capable of emitting pulsing light.

5. The aerosol generating system (102, 202, 302) of any one of claims 1 to 4, wherein the light-emitting device (132) further includes an additional multi-chromatic light-emitting diode (306) .

6. The aerosol generating system (102, 202, 302) according to any one of claims 1 to 5, wherein the first light output area (116) and/or the second light output area (120) includes a light diffuser (122, 126) .

7. The aerosol generating system (102, 202, 302) according to any one of claims 1 to 6, further including an optical bandpass filter (146, 216, 218) between the lightemitting device (132) and at least one of the first light output area (116) and the second light output area (120) .

8. The aerosol generating system (102, 202, 302) of any one of claims 1 to 7, wherein the light-emitting device (132) is configured to emit different colors at the same time and/or wherein the light-emitting device (132) is configured to switch through different colors, wherein the switching operation is performed at a frequency within 100 Hz and 10 kHz, and preferably within 100 Hz and 1 kHz

9. The aerosol generating system (102, 202, 302) of any one of claims 1 to 8, further including a light guide (146) between the light-emitting device (132) and at least one of the first light output area (116) and the second light output area (120) , and a lens (145) between the light-emitting device (132) and the light guide (146) .

10. The aerosol generating system (202) of any one of claims 1 to 9, wherein the case (104) includes a USB socket (204) , the multi-chromatic light-emitting diode (140) being able to emit light of a first color, the first light output area (116) including a first light diffuser (122) around the USB socket (204) , and the aerosol generating system (202) comprises a first optical bandpass filter (216) having an optical passband corresponding to the first color, the first optical bandpass filter (216) being in a first light path (134) between the light-emitting device (132) and the first light diffuser (122) .

11. The aerosol generating system (202) of any one of claims 1 to 10, wherein the case (104) includes a sidewall (210) having a side window (212) , the multi-chromatic lightemitting diode (140) being able to emit light of a second color, the second light output area (120) including a second light diffuser (126) on the side window (212) , and the aerosol generating system (202) comprises a second optical bandpass filter (220) having an optical passband corresponding to the second color, the second optical bandpass filter (220) being in a second light path (138) between the light-emitting device (132) and the second light diffuser (126) .

12. The aerosol generating system (202) of claim 11, wherein the multi-chromatic light-emitting diode (140) is able to emit light of a third color, the optical passband of the second optical bandpass filter (220) also corresponding to the third color.

13. The aerosol generating system (102, 202, 302) of any one of claims 1 to 12, wherein the case (104) includes a third light output area (118) arranged so that a part of light emitted by the light emitting device (132) may be diverted to the third light output area (118) .

14. The aerosol generating system (202) of claim 13, wherein the case (104) includes an oven cavity (206) adapted to at least partially receive a tobacco stick, the oven cavity (206) having an opening portion (208) , the multi-chromatic light-emitting diode (132) being able to emit light of a fourth color, the third light output area (118) comprising a third light diffuser (124) forming a continuous circle and/or a circular array of dots around the opening portion (208) , the aerosol generating system (202) further including a third optical bandpass filter (218) having an optical passband corresponding to the fourth color, the third optical bandpass filter (218) being in a third light path (136) between the light-emitting device (132) and the third light diffuser (124) .

15. The aerosol generating system (202) according to claim 13 or 14, further including a second beam splitter (214) able to divert a part of light having passed the first beam splitter (142) to the third light output area (118) .

16. A method of controlling an aerosol generating system (102, 202, 302) according to any one of claims 1 to 15, including a step of controlling the multi-chromatic lightemitting diode (140) in order to display at least two distinct light signals on the first light output area (116) and/or on the second light output area (120) .