WO2022207393A1

WO2022207393A1 - Luminaire for treating aerosol particles

Info

Publication number: WO2022207393A1
Application number: PCT/EP2022/057337
Authority: WO
Inventors: Peter Johannes Martinus BUKKEMS
Original assignee: Signify Holding B.V.
Priority date: 2021-04-02
Filing date: 2022-03-21
Publication date: 2022-10-06

Abstract

:The present invention relates to a luminaire (1) arranged to treat aerosol particles. The luminaire comprises a luminaire housing having an exterior surface that is exposed to the surroundings of the luminaire, the exterior surface comprising an air inlet surface (2) and an air outlet surface (4).The luminaire (1) further comprises an illumination light source for emitting visible light through a light exit window (16) that constitutes at least a portion of the air inlet surface (2), and an air disinfection cavity (5) being delimited by the air inlet surface (2) and the air outlet surface (4). The luminaire (1) comprises at least one disinfecting light source (6) arranged inside the air disinfection cavity (5) for emitting disinfecting light, and at least one air circulation device (7) arranged inside the air disinfection cavity (5) for providing an air flow through the air disinfection cavity (5). The air outlet surface (4) is a perforated surface that comprises a plurality of diffusing air outlet openings (8).

Description

Luminaire for treating aerosol particles

TECHNICAL FIELD

The present invention relates to a luminaire for treating aerosol particles.

BACKGROUND

In view of the recent development in the world concerning the global pandemic, disinfection has become a topic of renewed interest as the demand for sterilization increases. One way of disinfecting involves the use of UV light. As a response to pathogenic outbreaks involving airborne microorganisms it would be beneficial to employ UV light for disinfecting air and objects at locations where the transmission of such microorganisms is believed to occur.

It is established that small droplets of liquid, such as saliva and mucus, being dispersed in the air when people cough, sneeze, and talk thus forming an aerosol is the major source of spreading the pathogens. Therefore, capturing such droplets may to a large extent prevent further spread of pathogens, in particular the corona virus.

Currently available disinfecting devices aiming for treating aerosols normally comprise a disinfection chamber and means for creating a flow of air through the disinfection chamber. The contaminated air thus enters the disinfection chamber, wherein the pathogens are deactivated, usually by UV irradiation. The purified air exits the disinfection chamber and is mixed with the air in the room.

Disinfecting devices are increasingly being incorporated into luminaires to provide the luminaire with an additional disinfection functionality next to a lighting functionality.

Disinfection devices, particularly when incorporated into luminaires, suffer from the disadvantage of creating a large air distortion around the disinfection device (or luminaire), potentially creating particle clusters, thus impairing the ability of the disinfecting device to effectively capture pathogens-containing aerosol particles and allowing them to travel from one person to another. Therefore, there is a need to provide luminaire with a disinfection functionality that eliminates or minimizes the shortcomings discussed above, that effectively captures the aerosol particles and prevents its agglomeration and/or spread across the room.

SUMMARY

The present invention thus provides such a luminaire. The luminaire of the present invention may be particularly suitable for disinfecting office spaces, especially areas in vicinity of meeting tables or the like, around which people gather during a relatively long time period.

The luminaire according to the present invention is therefore arranged to treat aerosol particles discharged as droplets of saliva or mucus. Such particles are generated when people talk, cough or sneeze, and may have a diameter from 1 pm to 500 pm. Depending on the air flow speed in a room, the large particles having the diameter around 500 pm and above tend to drop towards the floor or the ground by gravitational force, while the smaller particles become airborne and may travel significant distances, following the air flow paths in the room. When people sit around a table of the like, such airborne particle may thus travel from one person to another, thus spreading pathogens. The aim of the present invention is therefore to effectively capture and disinfect such small airborne particles.

The luminaire according to the present invention comprises a luminaire housing, being a container for the various components of the luminaire. The luminaire housing has an exterior surface that is exposed to the surroundings of the luminaire. The exterior surface comprises an air inlet surface and an air outlet surface.

The air inlet surface comprises at least one air inlet opening arranged for admitting the air traveling across the air inlet surface into the luminaire.

The air inlet surface may be any suitable shape and size. In particular, the air inlet surface may be circular, rectangular, or polygonal. The air inlet surface may define an air inlet zone, being a volume in space partially delimited by the air inlet surface, wherein the air flow is directed towards the at least one air inlet opening. The size of the inlet surface should be adapted to the air throughput through the luminaire, such that the air traveling inside the air inlet zone does not exit the air inlet zone. By the term “air throughput” in the context of the present invention is understood a volume unit of air that passes through the luminaire per time unit. The luminaire may have an air throughput from 50 m³/h to 500 m³/h, preferably from 100 m³/h to 300 m³/h. In particular, when the air inlet surface is circular, it may have a diameter from 400 mm to 800 mm. The at least one air inlet opening may be arranged in the central portion of the air inlet surface. Further, a plurality of air inlet openings may be arranged on the air inlet surface. By the term “plurality” is meant two or more. The plurality of air inlet openings may be evenly distributed across the air inlet surface, or may be arranged in any other pattern, depending on the air flow conditions in the room. It is further conceivable that a plurality of air inlet openings may be activated individually, e.g. by means of opening a throttle, depending on the current situation in the room.

The at least one air inlet opening may have any suitable size and shape. In particular, the shape of the air inlet opening may be the same as the shape of the air inlet surface. If a plurality of air inlet openings is present, the shape and size of each air inlet opening may be same as or different from the shape and size of the other air inlet openings. The at least one air inlet opening may comprise at least one deflecting element, such as a baffle, a rim, or the like, arranged in order to facilitate entrance of the air into the disinfecting device.

As may be understood from the above, the air inlet surface should enable creating a relatively high inlet speed of air entering the air inlet zone, hereinafter referred to as a first inlet speed, normally being above maximum general application speed. By the term “maximum general application speed” is meant the air speed needed around the area of the people and the disinfecting device such that the air inlet speed is dominant is this area. Further, the relatively large area of the inlet surface enables creation of inward air flow lines around the luminaire. The luminaire should be arranged relatively close to the people sitting at the table, thus quickly capturing the aerosol particles created by each individual, preventing the aerosol particles from reaching the other individuals.

The luminaire further comprises an illumination light source for emitting visible light through a light exit window, wherein the light exit window constitutes at least a portion of the air inlet surface.

The disinfecting device further comprises an air disinfection cavity being delimited by the air inlet surface and the air outlet surface. The air disinfection cavity is arranged for accommodating the air to be purified. The size and shape of the air disinfection cavity may be adapted to the air throughput of the luminaire, as well as the residence time of the air inside the air disinfection cavity, i.e. the time needed to completely deactivate the pathogens.

In order to be able to deactivate the microorganisms, the luminaire comprises at least one disinfecting light source arranged inside the air disinfection cavity for emitting disinfecting light. The disinfecting light may have a wavelength in the range from 100 nm to 420 nm. In other words, the disinfecting light in the context of the present ivention may be purple light, or light having the ultraviolet wavelenght range. The ultraviolet wavelength range is defined as light in a wavelength range from 100 to 380 nm and can be divided into different types of UV light/UV wavelength ranges. With reference to Table 1, different UV wavelengths of radiation may have different properties and thus may have different compatibility with human presence and may have different effects when used for disinfection. In Table 1, a “+” sign indicates that light in the specific range has the indicated effect, while a sign indicates that the light in the specific range does not have the indicated effect. A “+/-“ sign indicates a moderate effect. As mentioned below, the effect may in itself be desired or undesired (e.g. ozone generation).

Table 1: Properties of different types of UV wavelength light

Each UV type/wavelength range may have different benefits and/or drawbacks. Relevant aspects may be (relative) sterilization effectiveness, safety (regarding radiation), and ozone production (as result of its radiation). Depending on an application, a specific type of UV light or a specific combination of UV light types may be selected and provides a superior performance over other types of UV light. UV-A may be (relatively) safe and may kill bacteria but may be less effective in killing viruses. UV-B may be (relatively) safe when a low dose (i.e. low exposure time and/or low intensity) is used, may kill bacteria, and may be moderately effective in killing viruses. UV-B may also have the additional benefit of production of vitamin D in a skin of a person or animal. Near UV-C may be relatively unsafe but may effectively kill bacteria and viruses. Far UV may also be effective in killing bacteria and viruses but may be (relatively to other UV-C wavelength ranges) (rather) safe. Far-UV light may generate some ozone which may be harmful for human beings and animals. Extreme UV-C may also be effective in killing bacteria and viruses but may be relatively unsafe. Extreme UV-C may generate ozone which may be undesired when coming in contact with human beings or animals. In some application, ozone may be desired and may contribute to disinfection, but then shielding of humans and animals may be desired. Hence, in the table “+” for ozone production especially implies that ozone is produced which may be useful for disinfection applications but may be harmful for humans/animals when they are exposed to it. Hence, in many applications this “+” may actually be undesired while in others, it may be desired.

The at least one disinfecting light source may be a solid-state light source such as a light-emitting diode, LED, and/or a laser diode. Further, the at least one disinfecting light source may be a low pressure mercury plasma lamp or an excimer light source. The at least one disinfecting light source may comprise a plurality of LEDs each of which emits the disinfecting light.

The term “LED” as used in the context of the present invention implies any type of LED known in the art, such as inorganic LED(s), organic LED(s), polymer/polymeric LEDs, violet LEDs, blue LEDs, optically pumped phosphor coated LEDs, optically pumped nano-crystal LEDs. As used herein, the term “LED” can encompass a bare LED die arranged in a light mixing chamber, which may be referred to as a LED package. When UV-C light is used, the LED may be mounted in a cavity covered in a non-contact manner by an emission window made from quartz/fused silica.

The plurality of LEDs may comprise at least 10 LEDs, preferably at least 20 LEDs, more preferably at least 30 LEDs.

The luminaire may comprise a plurality of disinfecting light sources. Each disinfecting light source of the plurality of disinfecting light sources may emit a disinfecting light in the wavelength range being same as or different from the wavelength range of the other disinfecting light sources. The disinfecting light sources may be used together or may be operated individually depending on the type of microbiological species that needs to be deactivated.

The luminaire of the present invention further comprises at least one air circulation device arranged inside the air disinfection cavity for providing an air flow through the air disinfection cavity. The air circulation device may be a fan, in particular a 120 mm (pc) fan, a blower or the like. The air circulation device should be able to deliver the necessary air throughput and the air pressure difference.

The air outlet surface comprised in the exterior surface of the luminaire housing is a perforated air outlet surface. By the term “perforated” in the context of the present invention is meant a surface comprising a plurality of openings. The plurality of openings may be introduced to the air outlet surface by means of perforation or the like, or may be naturally occurring in the material of the air outlet surface, e.g. in the case when the air outlet surface is manufactured of a porous material, i.e. a material containing pores or voids. According to the present invention, the air outlet surface comprised in the exterior surface of the luminaire housing comprises a plurality of diffusing air outlet openings. By the term “diffusing” is herein understood that the plurality of air outlet openings is arranged to diffuse the air leaving the air disinfection cavity, i.e. to spread the air evenly in a non- localized manner, thus avoiding high outlet speed potentially leading to buildup of particle clusters or stagnant areas, wherein the aerosol particle may reside. The major advantage of the present invention is thus the fact that due to diffusion of the purified air rather than a bulky flow, cluster formation is avoided, thus leading to an effective capturing of the aerosol particles. Further, the low speed and even distribution of the purified air around the luminaire pushes the non-purified air away from the luminaire, thus creating a “clean” area in the vicinity of the luminaire, thus increasing safety of the people gathered around the luminaire.

The air outlet surface may be manufactured of any suitable material, such as fabric, porous mineral, 3D printed perforated plastics, perforated metal, or the like, as long as the outlet speed is substantially equal to or lower than the general designed application air flow speed and diffusion of the air released through the air outlet surface is achieved. In the context of the present invention, “general designed application air flow speed” is to be understood as the air flow speed when the disinfection functionality of the luminaire is turned off or when there is no luminaire present. The general designed application air flow speed may be different for different applications and is normally around 0.1 m/s to 0.2m/s in an office.

The shape of the air outlet surface may vary depending on the overall design of the luminaire. In particular, the air outlet surface may be rectangular or hemispheric. The size of the air outlet surface should be sufficient for providing an adequate diffusion of the purified air, and at the same time small enough to avoid bulkiness which may block the view when the luminaire is arranged between people sitting around a table. In particular, the area of the air outlet surface may be from 0.2 m² to 1.5 m². The area of the air outlet surface may be greater than the area of the air inlet surface.

Since the air outlet surface according to the present invention provides diffusion of the purified air through the plurality of air outlet openings when the disinfection functionality of the luminaire is in operation, air pressure inside the air disinfection cavity may be greater than the air pressure outside the air outlet surface of the luminaire.

During operation of the luminaire according to the present invention, the air circulation device will create an air flow through the luminaire. The air flow thus enters the air inlet zone partially delimited by the air inlet surface comprised in the luminaire housing of the luminaire at a first air inlet speed and travels along the air inlet surface towards at least one air inlet opening. The air flow subsequently enters the air disinfection cavity through the at least one air inlet opening at a second inlet speed and exits the air disinfection cavity through the diffusing air outlet openings at an outlet speed. The first inlet speed should be high enough in order to effectively move the air from a person across the air inlet zone towards the at least one air inlet opening. At the same time, the first inlet speed should not be so high that a person perceives the air flow as a disturbing wind. In particular, the first inlet speed may be from 0.1 m/s to 0.5 m/s. Alternatively or additionally, the first inlet speed may be at least 0.1 m/s greater than the maximum general application speed around the disinfecting device, such that air flow towards the at least one air inlet opening becomes dominant. The second inlet speed may be significantly greater than the first inlet speed, depending on the size of the air inlet surface and the size of the at least one air inlet opening. In particular, the second inlet speed may be at least 1 m/s, preferably at least 1.5 m/s, more preferably at least 2 m/s. Since individuals in the vicinity of the luminaire will be positioned at a significant distance from the at least one air inlet opening, the second inlet speed will not be perceived as disturbing or unpleasant.

In order to provide a sufficient diffusion of the purified air, such that cluster formation is avoided, and such that the purified air creates a clean area around the luminaire, the outlet speed may be substantially equal to or lower than the air speed outside the air outlet surface comprised in the exterior surface of the luminaire housing of the luminaire. By the term “substantially equal” is understood the outlet speed being slightly higher or equal to the air speed outside the air outlet surface of the luminaire. In particular, the outlet speed may be from 0.01 m/s to 0.1 m/s, preferably from 0.02 m/s to 0.9 m/s, more preferably from 0.03 m/s to 0.8 m/s. The luminaire according to the present invention may comprise an air disinfection chamber arranged inside the air disinfection cavity. In such an embodiment, the at least one disinfecting light source may be arranged inside the air disinfection chamber. The size of the air disinfection chamber maybe adapted to the required air throughput of the luminaire and the residence time of the air inside the air disinfection chamber. In order to achieve a satisfactory degree of disinfection, the residence time inside the air disinfection chamber may be at least 0.2 s. Thus, the air disinfection chamber may have a volume from 5 to 20 dm³.

The air disinfection chamber may be delimited by an upper and a lower disinfecting light shield. Such a shield is arranged for preventing the disinfecting light from escaping the luminaire thus eliminating the risk of exposure of subjects in the vicinity of the luminaire to harmful irradiation. Further, the upper and/or lower disinfecting light shield may function as air flow modifier, e.g. for directing the air flow in the desired direction. The upper and the lower disinfecting light shield may be made of the same material or different materials. The upper and/or lower disinfecting light shield may be made from black polycarbonate.

Alternatively, or additionally, the air disinfection chamber may comprise a separate air modifier. Such an air modifier may be needed for adjusting the speed of the air flow inside the air disinfection chamber, or for directing the air flow in the desired direction. Further, the air modifier creates a “swirl” inside the air disinfection chamber thus preventing air short circuits. A plurality of air modifiers may be arranged for optimal prevention of short circuits. Moreover, the spiral air flow prevents dust from collecting on the disinfecting light source.

The luminaire comprises at least one illumination light source for providing visible light, e.g. light in the visible wavelength range. By the term “visible wavelength range” in the context of the present invention is understood a wavelength range from 380 nm to 750 nm. It is conceivable that the luminaire comprises a plurality of illumination light sources, each providing visible light in the visible wavelength range being the same as or different from the visible wavelength range of the visible light emitted by the other illumination light sources.

The luminaire comprises a light exit window through which the visible light may be emitted. The light exit window constitutes at least a portion of the air inlet surface. The luminaire may comprise a plurality of light exit windows. Position, material, size, and shape of the plurality of the light exit windows may be adapted to a desired architecture of the luminaire.

The illumination light source adapted for, in operation, emitting visible light may for instance be provided as a solid state light source, e.g. white LEDs, as phosphor converted UV LEDs and/or blue LEDs, as RGB LEDs, or as a laser light source, or as a super luminescent diode.

The luminaire may comprise a controller for controlling the at least one disinfecting light source and the at least one illumination light source. The illumination light source may be used for general lighting or may be used as an alert signal to the user whenever the disinfecting light source is powered. In particular, the illumination light source may emit flashing light or red light when the disinfecting light source is operating, such that the user is aware of the presence of potentially harmful irradiation.

The luminaire may be arranged to be suspended from a ceiling of a room, or it may be a free-standing device for positioning on a surface of a table or on any other suitable surface. Regardless of the design, it is important that both the air inlet surface and the air outlet surface are in contact with the surroundings of the luminaire (also referred to as the ambient). The preferred embodiment is a suspended luminaire, since such a luminaire does not require a surface area of e.g. a table, thus providing a neat arrangement. Another advantage of a suspended luminaire is the sufficient space is available above and below the luminaire, such that an efficient air flow can be established around the luminaire. In the embodiment wherein the luminaire is a suspended luminaire, the luminaire may comprise a suspending element for suspending the luminaire from a ceiling of a room.

The luminaire as described above, when arranged in a room, is a part of an air disinfecting system for treatment of aerosol particles. In order to create an efficient air flow towards the inlet opening, such that the aerosol particles are captured as soon as they reach the air inlet opening, the air disinfecting system comprises a guiding surface arranged substantially parallel to the air inlet surface comprises in the exterior surface of the luminaire housing at a distance D from the inlet surface. Such a guiding surface enlarges the area wherein the air is moving towards the at least one air inlet opening and creates a buffer zone between the air inlet surface and the air outlet surface. Such a guiding surface may be attached to the luminaire housing of the luminaire or it may be a portion of a piece of furniture already being present in the room, such as a tabletop. The distance D may be from 300 mm to 1000 mm. The guiding surface may be of any suitable size and shape, such as circular, rectangular, or polygonal. Preferably, the shape of the guiding surface is the same as the shape of the air inlet surface. Since a clean area wherein no aerosol particles are present will be created around the luminaire as described above, the individuals should be positioned around the luminaire such that a straight line between two adjacent individuals at least partially runs through the clean area.

Considering the above, the luminaire of the present invention provides efficient capturing of aerosol particles in the air, in particular in areas where people generate such particles.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the invention will now be described by way of example with reference to the accompanying drawings, of which:

Fig. 1 is an exploded view of a luminaire according to the present invention;

Fig. 2 shows a cross-section view of the luminaire depicted in Fig. 1;

Fig. 3 depicts an air disinfecting system;

Fig. 4 illustrates a top view of an air disinfecting system;

Figs. 5 and 6 illustrate the air flow in an air disinfecting system.

All the figures are schematic, not necessarily to scale, and generally only show parts which are necessary in order to elucidate embodiments of the present invention, wherein other parts may be omitted or merely suggested.

DETAILED DESCRIPTION

The present invention will now be described hereinafter with reference to the accompanying drawings, in which exemplifying embodiments of the present invention are shown. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments of the present invention set forth herein; rather, these embodiments of the present invention are provided by way of example so that this disclosure will convey the scope of the invention to those skilled in the art. In the drawings, identical or similar reference numerals denote the same or similar components having a same or similar function, unless specifically stated otherwise.

Figs. 1 and 2 illustrate one embodiment of the luminaire 1 according to the present invention. The luminaire 1 in the form of a pendant luminaire comprises a luminaire housing having an exterior surface that is exposed to the surroundings of the luminaire. The exterior surface comprises a circular air inlet surface 2. The air inlet surface 2 comprises a plurality of illumination light sources in the form of LED modules. The air inlet surface 2 comprises one air inlet opening 3 arranged for admitting the air traveling across the air inlet surface 2 into the luminaire 1. The air inlet opening 3 is arranged in the central portion of the air inlet surface 2. The air inlet opening 3 in Figs. 1 and 2 is circular.

As may be understood from the above, the air inlet surface 2 should enable creating a relatively high first inlet speed below the air inlet surface 2, normally being above maximum general application speed. Further, the relatively large area of the inlet surface 2 enables creation of inward air flow lines around the luminaire 1, as will be described in greater detail below.

The luminaire 1 further comprises an air outlet surface 4, and an air disinfection cavity 5 being delimited by the air inlet surface 2 and the air outlet surface 4. The air disinfection cavity 5 is arranged for accommodating the air to be purified. As may be seen in Figs. 1 and 2, the air disinfection cavity 5 is substantially hemispheric.

In order to be able to deactivate the microorganisms, the luminaire 1 comprises two disinfecting light sources 6 arranged inside the air disinfection cavity 5 for emitting disinfecting light.

The luminaire 1 further comprises at least one air circulation device 7 arranged inside the air disinfection cavity 5 for providing an air flow through the air disinfection cavity 5. The air circulation device 7 depicted in Figs. 1 and 2 is a fan.

The air outlet surface 4 comprised in the exterior surface of the luminaire housing of the luminaire 1 comprises a plurality of substantially elliptic diffusing air outlet openings 8. The air outlet surface 4 is substantially hemispheric. The area of the air outlet surface 4 is greater than the area of the air inlet surface 2 in order to achieve the sufficiently low outlet speed of air exiting the air disinfection device 1.

The luminaire 1 comprises an air disinfection chamber 9 arranged inside the air disinfection cavity 5. The disinfecting light sources 6 are arranged inside the air disinfection chamber 9. The air disinfection chamber 9 is delimited by an upper disinfecting light shield 10 and a lower disinfecting light shield 11.

The air disinfection chamber 9 comprises two air modifiers 12, 13, and two reflectors 14, 15. The luminaire 1 comprises a light exit window 16 through which the visible light may be emitted.

Fig. 3 shows an air disinfecting system 100. The luminaire 1 is suspended from a ceiling and comprises an air inlet surface 2 and an air outlet surface 4 comprising a plurality of diffusing air outlet openings 8. In order to create an efficient air flow 18 towards the inlet opening 3, such that the aerosol particles are captured as soon as they reach the air inlet opening 3, the disinfecting system 100 comprises a guiding surface 17 arranged substantially parallel to the air inlet surface 2 of the luminaire 1 at a distance D from the air inlet surface 2. In Fig. 3, the guiding surface 17 is a tabletop.

Fig. 4 illustrates the air disinfecting system 100 seen from above. As may be seen in Fig. 4, the guiding surface 17 is a tabletop of a round table, around which three individuals 19 are arranged. The luminaire 1 is suspended from the ceiling above the central portion of the guiding surface 17. The dashed area illustrates the air inlet zone 20 as describe above, wherein the air flow is directed towards the air inlet opening 3. In other words, once the air flow containing aerosol particles has entered the air inlet zone 20, it will not be able to leave the air inlet zone 20, but will necessarily proceed towards the air inlet opening 3 and in to the air disinfection chamber 9, wherein the aerosol particles will be disinfected. The individuals 19 are positioned around the table such that a straight line between two adjacent individuals at least partially runs through the air inlet zone 20.

Fig. 5 illustrates an air disinfecting system 100, wherein the luminaire 1 is arranged as a suspended or pendant luminaire above a table, wherein the tabletop constitutes the guiding surface 17. As may be seen in Fig. 5, the air flow 18 is created from each individual 19 towards the air inlet surface 2, such that a clean area 20 is created around the luminaire 1.

Fig. 6 depicts an air disinfecting system 100 similar to the one shown in Fig. 5. The air outlet surface 4 of the luminaire 1 comprises a plurality of diffusing air outlet openings 8 such that the air 21 leaving the air disinfection cavity is spread evenly in a non- localized manner, thus avoiding the buildup of particle clusters or stagnant areas, wherein the aerosol particle may reside. Due to diffusion of the purified air 21 and its low speed, the non- purified air is pushed away from the luminaire 1, thus creating a “clean” area 22 in the vicinity of the luminaire 1, thus increasing safety of the people 19 gathered around the luminaire 1.

Although the present invention has been described with reference to various embodiments, those skilled in the art will recognize that changes may be made without departing from the scope of the invention. It is intended that the detailed description be regarded as illustrative and that the appended claims including all the equivalents are intended to define the scope of the invention. While the present invention has been illustrated in the appended drawings and the foregoing description, such illustration is to be considered illustrative or exemplifying and not restrictive; the present invention is not limited to the disclosed embodiments. Other variations to the disclosed embodiments can be understood and effected by those skilled in the art in practicing the claimed invention, from a study of the drawings, the disclosure, and the appended claims. In the appended claims, the word “comprising” does not exclude other elements or steps, and the indefinite article ”a” or “an” does not exclude a plurality. The mere fact that certain measures are recited in mutually different dependent claims does not indicate that a combination of these measures cannot be used to advantage. Any reference signs in the claims should not be construed as limiting the scope.

Claims

CLAIMS:

1 A luminaire (1) arranged to treat aerosol particles, the luminaire (1) comprising: a luminaire housing having an exterior surface that is exposed to the surroundings of the luminaire (1), the exterior surface comprising an air inlet surface (2) and an air outlet surface (4); an illumination light source for emitting visible light through a light exit window (16) that constitutes at least a portion of the air inlet surface (2), an air disinfection cavity (5) being delimited by the air inlet surface (2) and the air outlet surface (4); a disinfecting light source (6) arranged inside the air disinfection cavity (5) for emitting disinfecting light; an air circulation device (7) arranged inside the air disinfection cavity (5) for providing an air flow through the air disinfection cavity (5); wherein the air inlet surface (2) comprises an air inlet opening (3), wherein the air outlet surface (4) is perforated to comprise a plurality of air outlet openings (8), and wherein the plurality of air outlet openings (8) is arranged to spread air leaving the air disinfection cavity (5) evenly in a non-localized manner.

2. The luminaire (1) according to claim 1, wherein the air flow exits the air disinfection cavity (5) through the diffusing air outlet openings (8) at an outlet speed, and wherein the outlet speed is substantially equal to or lower than 0.2 m/s.

3. The luminaire (1) according to any one of the preceding claims, wherein the luminaire (1) comprises an air disinfection chamber (9) arranged inside the air disinfection cavity (5), and wherein the disinfecting light source (6) is arranged inside the air disinfection chamber (9).

4. The luminaire (1) according to claim 3, wherein the air disinfection chamber (9) is delimited by an upper disinfecting light shield (10) and a lower disinfecting light shield (11).

5. The luminaire (1) according to any one of claims 3 and 4, wherein the air disinfection chamber (9) comprises an air modifier (12).

6. The luminaire (1) according to any one of the preceding claims, wherein the disinfecting light source is arranged to emit disinfecting light having wavelength in the range from 100 nm to 420 nm.

7. The luminaire (1) according to any of the preceding claims, wherein the luminaire has an air throughput from 50 m³/h to 300 m³/h.

8. The luminaire (1) according to any one of the preceding claims, wherein, in operation, the air flow enters an air inlet zone partially delimited by the air inlet surface (2) at a first air inlet speed and travels along the air inlet surface (2) towards the air inlet opening (3), the first inlet speed being at least 0.1 m/s.

9. The luminaire (1) according to any one of the preceding claims, wherein, in operation, the air flow exits the air disinfection cavity (5) through the diffusing air outlet openings (8) at an outlet speed below 0.1 m/s.

10. The luminaire (1) according to any one of the preceding claims, wherein the air disinfection chamber (9) has a volume from 5 to 20 dm³.

11. The luminaire (1) according to any one of the preceding claims, wherein the luminaire (1) comprises a suspending element for suspending the luminaire (1) from a ceiling of a room.