TECHNICAL FIELD

The invention relates to an illumination system capable of implementing a lighting functionality as well as an air treatment (disinfecting or purifying) functionality.

BACKGROUND OF THE INVENTION

There is an increasing interest - due to health and safety concerns - to protect people in both personal homes and in office environments from the spread of bacteria and viruses, such as influenza or against the outbreak of novel viruses like the recent CO VID-19 pandemic. In the consumer domain (single) air purifying devices are used of which some have ionizing generators included that can kill bacteria and viruses when air ion density is at the correct level, thus improving the indoor air quality (IAQ).

As with water, the public has become more concerned with the quality of its air. Many factors in our environment have put pressure on our air quality.

Tighter homes and buildings (i.e., less fresh air and ventilation).

Energy saving measures.

Decrease in the quality of outdoor air.

Substantial increases in the incidence of asthma.

Sick building syndrome.

The realization that mold (fungi) in the air can cause serious health problems within a building.

Therefore, there is a need for an illumination system for use in personal homes, but also in free accessible areas, such as office spaces, public spaces or e.g. supermarkets, capable of implementing a lighting functionality as well as an air treatment (disinfecting or purifying) functionality, whilst maintaining its outer appearance of an illumination system without adversely affecting its air treatment functionality.

SUMMARY OF THE INVENTION

According to a first aspect of the invention an illumination system is proposed, comprising a support structure; at least one light emitting source coupled with the support structure for emitting visible light source light towards a light emission window; at least one ion generating source coupled with the support structure for generating and emitting ionized molecules in air towards the light emission window; wherein the light emission window being formed of a visible light source light transmissive and at least partly air permeable material; wherein the support structure and the light emission window are separated by a space which is divided in multiple compartments by means of compartment walls; and wherein the at least one light emitting source and the at least one ion generating source are not accommodated together in a same, single compartment of the multiple compartments.

Thus, its outer appearance of an illumination system is maintained without adversely affecting its air treatment functionality, allowing the advantage of mounting an ion generating source without extensive altering of the outer appearance thereof. In particular, the at least one light emitting source and the at least one ion generating source, also referred to as ionizer, are not accommodated together in a same, single compartment of the multiple compartments, means that ionizer and light emitting source are always physically separated by at least one wall and hence are accommodated in mutually separate compartments. As ionizers create static charged pollution like dust and particles, said static charged pollution may collect and accumulate on parts of the illumination system. Typically said pollution is light absorbing and local accumulation of said pollution can cause significant light losses. By physically and spacely separating the ionizers and the light sources, the risk of accumulation of said pollution near light sources is counteracted, and hence the occurrence of said significant light losses is reduced and/or at least delayed. Furthermore, if ionizers and light sources are accommodated in a single, large compartment, there is a risk on “dead comers” in such a large compartment where air treatment (purification, disinfection) is less effective or hampered.

In an aspect, the visible light source light transmissive and air permeable material is a flexible material, in particular the flexible material is a non-woven or a woven fabric. In all examples mentioned above, the light emission window maintains both its outer appearance of an illumination system or device in terms of light transmissivity as well as permeability for ionized molecules being emitted, thus guaranteeing air purification.

In particular, the permeable material has a plurality of pores, rendering the permeable material to have an air permeability in the range of 2 cm ³ /cm ² /s to 150 cm ³ /cm ² /s.

In another advantageous example, the part of the at least partly air permeable light emission window directly facing the at least one ion generating source has an air permeability, which is higher than that of the part of the light emission window not directly facing the at least one ion generating source. Herewith, an improvement is achieved as to the emittance of ionized molecules from the ion generating source and the illumination system towards the area (home or office environment) where the illumination system is installed.

In an alternative example, which also enhances the emittance of ionized molecules from the ion generating source and the illumination system towards the area (home or office environment) where the illumination system is installed, the space between the support structure and the light emission window is divided in at least one compartment by means of compartment walls, with the at least one compartment containing at least one ion generating source. In an example, the compartment walls form a tubular shaped duct provided around the at least one ion generating source for guiding emitted ionized molecules towards the light emission window.

Preferably, the compartment walls have a first wall end mounted to the support structure and a second wall end facing the light emission window, and the compartment walls have a longitudinal length extending between the first and second wall end , which length is smaller than a distance between the support structure and the light emission window. Yet, these walls may extend over the full distance between the support structure and the light emission window, for example in that the length of the first and second walls is equal to said distance. Herewith contact between and damage to the light emission window by the compartment walls, as well as shadowing effects of the tubular shaped duct created by neighboring light emitting sources are avoided.

Alternatively, the compartment walls are mounted with the second wall end to the light emission window, for example by means of glue or hot melt. As the tubular shaped duct now contacts the light emission window damage is avoided by manufacturing the tubular shaped duct from a flexible material, for example a polymer, e.g. silicone or polyurethane.

Additionally, the compartment walls are made from a translucent material, more in particular from a transparent material. Herewith shadowing effects of the compartment walls created by neighboring light emitting sources are avoided, both in the non-contacting as contacting example.

In order to further improve the emittance of ionized molecules from the ion generating source and the illumination system towards the area (home or office environment) where the illumination system is installed, the illumination system is provided with an air fan device. Preferably, only the compartment(s) accommodating the ionizer(s) or the ionizer(s) itself is/are provided with the air fan device(s). Air is then preferentially flowing along the ionizer and not along the light sources, hence obviating the collection and accumulation of particles/dust at the light sources, but rather said collection of dust occurs near or at the ionizers.

Preferably, the illumination system is provided with multiple ion generating sources distributed over the support structure, for example at least 4, more preferably at least 100, most preferably at least 1000 ion generating sources.

In yet another example, the illumination system comprises at least one sensor for detecting a level of ionized molecules emitted in air as well as a control device for controlling the at least one ion generating source in response to the level of ionized molecules emitted in air being detected.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be discussed with reference to the drawings, which show in:

Figs. 1-10 schematically illustrate details of several examples of an illumination device according to the present disclosure.

DETAILED DESCRIPTION OF THE INVENTION

For a proper understanding of the invention, in the detailed description below corresponding elements or parts of the invention will be denoted with identical reference numerals in the drawings.

As outlined in this disclosure the invention relates to an illumination system capable of implementing both a lighting functionality as well as an air treatment (disinfecting or purifying) functionality. For example the invention relates to an illumination system capable for disinfection an area in which the illumination system is installed, in particular disinfection the area using ionized air. In particular an illumination system for disinfection using ionized air for killing bacteria and/or viruses.

In Figure 1 a first example of an illumination system according to the disclosure is depicted and denoted with reference numeral 101. The illumination system 101 can be mounted either on the ground floor or at the ceiling 1000 (only shown in Figure 1) of a free accessible area, such as a personal home or office spaces, or public spaces, such as theatre’s, cinema’s or supermarkets.

In all examples of the illumination systems shown in the Figures (denoted with 101-102-103-104-105-106-107-108), it comprises a support structure 10. The support structure 10 may be part of a housing (not depicted) of the luminaire. The support structure 10 may contain or comprise electric circuitry and electric components for providing electric power to the several components of the illumination system 101-102-103-104-105-106-107- 108.

One of those functional components of the illumination system 101 (101-102- 103-104-105-106-107-108) is depicted with reference numeral 30, being a light emitting source. The light emitting sources 30 are coupled at regular intervals or in a desired pattern with the support structure 10 and are arranged for emitting light in the visible wavelength range (denoted with h.v ). Preferably the support structure 10 has a flat geometry, in particular at the area where the light emitting sources 30 are mounted. In order to assist in the illumination functionality, the material of the support structure 10 can be highly reflective (>85%, >90%, >92%), allowing light emitted by the light emitting sources 30 in the direction of the support substrate 10 to be reflected in a direction away from the support structure 10 and preferably out of the illumination system.

Although in the Figures the examples of the illumination systems 101-102- 103-104-105-106-107-108 are shown with a limited number (6) of light emitting sources 30, it is noted that other examples might incorporated a single light emitting source 30 or more than 6, such as 20, 40 or 100 light emitting sources 30.

The light emitting sources 30 can be configured as any type of light source, either (O)LEDs, incandescent light bulbs, fluorescent beam lights, etc. etc. or a combination of solid state light sources such as LEDs and/or lasers, for example at least 5 LEDs and/or 5 lasers.

Another functional component of the illumination systems 101-102-103-104- 105-106-107-108 is an ion generating source 40. The ion generating source 40 is also mechanically and electrically mounted or coupled with the support structure 10 and designed for at least generating ionized molecules in air, denoted with I+/I-. The ion generating source 40 can be a negative ion generator or a Chizhevsky's chandelier. It uses a high voltage to ionize (electrically charge) air molecules. Negative ions, or anions, are particles with one or more extra electrons, conferring a net negative charge to the particle. Cations are positive ions missing one or more electrons, resulting in a net positive charge.

The at least one ion generating source 40 emits the ionized molecules in air I+/I- towards a light emission window 20. The light emission window 20 is disposed at some distance D from the support structure 10, thus forming a space 11. Preferably, the light emission window 20 is being formed of a visible light source light transmissive and at least partly air permeable material.

Herewith, its outer appearance of the illumination system of either example shown in the Figures, is maintained without adversely affecting its air treatment functionality, and allows the advantage of mounting an ion generating source 40 inside the illumination system 101-102-103-104-105-106-107-108 without extensive altering of the outer appearance thereof.

As to the transmittance T of the light emission window 20 it is noted that it preferably has a transmittance for visible light in the range of 40 to 80%, i.e. high enough to counteract too much light loss, and low enough to render light sources and/or ion generators unobtrusive and to render the illumination system to have a relatively uniform light output at its light emission window.

In an aspect, the visible light source light transmissive and air permeable material of the light emission window 20 is a flexible material, in particular the flexible material is a non-woven or a woven fabric. In all examples mentioned above, the light emission window 20 maintains both its outer appearance of an illumination system or device in terms of light transmissivity as well as permeability for ionized molecules I+/I- being emitted, thus guaranteeing air purification of the free accessible area, such as a personal home or office spaces, or public spaces, such as theatre’s, cinema’s or supermarkets in which the illumination system is installed.

The air permeability of a fabric is influenced by several factors: the type of fabric structure, the design of a woven, the number of warp and weft yams per centimeter (or inch), the amount of twist in yams, the size of the yarns and the type of yam structure. Therefore, establishing a more complex theory expressing the air permeability related to all fabric parameters, for example a capillary model of porous systems on Darcy's law, will bring out difficulties. In particular, the permeable material has a plurality of pores, typically resulting in an air permeability of the permeable material in a range of 2 cm ³ /cm ² /s to 150 cm ³ /cm ² /s, preferably 5 cm ³ /cm ² /s to 100 cm ³ /cm ² /s, such as 20 cm ³ /cm ² /s. The air permeability is defined as the volume of air in milliliters (cm ³ ) which is passed in one second through 1 cm ² of the fabric at a pressure difference of 10 mm head of water, see R.T. Ogulata, Air Permeability of Woven fabrics, Journal of Textile and Apparel, Technology and Management Vol. 5-2, Summer 2006, 1-10. The pores may have various shapes, such as round, oval , square, rectangular or polygonal. The pores may be perforations in a non-woven material, for example a foil material. Yet, the pores also may be openings in a woven fabric produced by weft and warp yams, then the pores typically have a square or rectangular shape.

Preferably the diameters of round pores or sides of square pores of the permeable material (woven or non-woven fabric) are less than 5mm, for example less than 2 mm, more preferably less than 1 mm, such as less than 0.1 mm, for example 0.05 mm to 0.01mm. The permeable material has a pore density DS comprising a plurality of N pores per unit surface area A in dm ² , wherein DS = N/A and DS >= 10/dm ² , more preferably DS >= 100/dm ² , most preferably DS >= 1000/dm ² . The pores have a pore opening area OA, wherein OA is preferably in the range from 0.0004 to 9 mm ² , more preferably 0.01 to 2 mm ² , most preferably 0.05 to 1 mm ² . Larger pores i.e. > 1 mm ² are desired when no fan is used or when a fan provide a limited forced fluid flow. Smaller pores i.e. OA < 1mm ² are desired when the DS is relatively high, for example DS > 1000 dm ² .

The example of Figure 2 depicts an illumination system 102 wherein the space 11 between the support structure 10 and the light emission window 20 is divided in at least one compartment by means of compartment walls, with the at least one compartment containing at least one ion generating source 40. In Figures 2-7 the compartment is being formed as a tubular shaped duct 41 mounted closely around the at least one ion generating source 40, whereas in the examples of Figures 9 and 10 the compartment is denoted with reference numeral 60 having a significant larger dimension than the tubular shaped duct 41 of Figures 2-8 closely mounted around the ion generating source 40.

In either embodiment of the compartment, it houses at least one ion generating source 40, wherein the examples of Figures 9 and 10 also allow for the housing or accommodation of one or more light emitting sources 30. Furthermore, in either example of Figures 2-10 the compartment is formed of compartment wall, indicated by reference numeral 41 in Figures 2-8 and by reference numerals 60a-60b in Figures 9 and 10.

When looking at Figure 2, preferably, compartment walls of the compartment are formed as a tubular shaped duct 41, which is provided directly and closely around the ion generating source 40. The tubular shaped duct 41 serves to guide the emitted ionized molecules I+/I- towards the light emission window 20. Hereto, the tubular shaped duct 41 (compartment wall) has a first duct (or wall) end 41a mounted to the support structure 10 and a second duct (or wall) end 41b facing the light emission window 20.

In the example of Figure 2, the compartment walls forming the tubular shaped duct 41 have a longitudinal length L extending between the first and second duct/wall ends 4 la-4 lb, which duct/wall length L smaller than a distance D between the support structure 10 and the light emission window 20, D typically being the height of the space between the support structure and the light emission window.. This is denoted in Figure 2 by means of the inner space x between the light emission window 20 and the free duct end 41b. Thus, in the example of Figure 2 the tubular shaped duct 41 does not contact the light emission window 20 and damage to the thin, flexible and thus damage-susceptible light emission window is avoided. Also, shadowing effects of the tubular shaped duct 41 created by neighboring light emitting sources 30 do not occur.

Figure 4 shows an example of an illumination system 103 implementing multiple ion generating sources 40, being mounted as irregular or regular interval to the support structure 10 and between the light emitting sources 30. Also here multiple compartments are provided in the space between the support structure 10 and the light emission window 20. In fact, the several ion generating sources 40 are each provided with a tubular shaped duct 41, which functions as the compartment, around the ion generating source 40. Similar as in Figure 2 (and all other examples of this disclosure) the tubular shaped duct 41 is mounted with its first duct/wall end 41a to the support structure 10. The compartment/tubular shaped duct 41 serves to guide the emitted ionized molecules I+/I- towards the light emission window 20. In Figure 4, the several tubular shaped ducts 41 do not contact the light emission window 20 similar as in the example of Figure 2.

It is noted that the number of ion generating sources 40 can be for example at least 4, more preferably at least 100, most preferably at least 1000 ion generating sources.

Alternatively, see the example of the illumination system 104 of Figure 5 the compartment walls, which form the tubular shaped duct 41 are also mounted with the second duct/wall end 41b to the light emission window 20, for example by means of glue or hot melt. Thus the length L of the tubular shaped duct 41 (hence length of the compartment wall) is equal to the distance D between the support structure 10 and the light emission windows 20. As the tubular shaped duct 41 now contacts the light emission window 20 damage is avoided by manufacturing the tubular shaped duct 41 from a flexible material, for example a polymer, e.g. silicone or polyurethane.

This is shown in the example of the illumination system 105 of Figure 7, where the compartment wall forming the flexible tubular shaped duct 41’ is capable of a temporarily bending or bulging due to a displacement of the light emission window 20 for example due to wind circulation or due to manipulation of the light emission window 20 by people. Also, in the example of Figure 5 the compartment wall forming the tubular shaped duct 41 is made from a translucent material, more in particular from a transparent material, thus avoiding any shadowing effects of the tubular shaped duct created by neighboring light emitting sources are avoided. It is noted that the compartment wall forming the tubular shaped duct 41 can be made from a translucent material, more in particular from a transparent material, in both in the non-contacting example of Figure 2-4 as in the contacting examples of Figures 5-10 as such material in bot situations advantageously avoids such shadowing effects.

Figures 3, 6, 9 and 10 show a further detail of the light emission windows 20, which is formed of a visible light source light transmissive and at least partly air permeable material. The aspect of the light emission window 20 being at least partly air permeable for the ionized air being generated by the several ion generating sources 40 is shown in detail in the Figure 3, 6, 9 and 10. The examples of the illumination systems 102-104-106-107-108 in these Figures show a part of the light emission window 20 being denoted with reference numeral 21. In the examples shown, said part 21 of the light emission window 20 is directly facing the at least one ion generating source 40 and said part 21 has an air permeability, which is higher than that of a part of the light emission window 20 not directly facing the at least one ion generating source 40. Here the emittance is improved of ionized molecules I+/I- from the ion generating source 40 and the illumination systems 102-104-106-107-108 towards the area (home or office environment) where the illumination system is installed.

The permeability of the area part 21 of the light emission window may be at least 10 times higher than the permeability of the other area part of the light emission window 20 not directly facing the at least one ion generating source 40. Furthermore, the area of the area part 21 may be smaller than the other area part of the light emission window 20 not directly facing the at least one ion generating source 40, for example 5 times smaller than of that area part of the light emission window 20 not directly facing the at least one ion generating source 40.

In another specific example, said part 21 can formed as one large opening in of the light emission window 20 directly exposing the at least one ion generating source 40 towards the area (home or office environment).

To further enhance the emittance of ionized molecules I+/I- from the ion generating source 40 and the illumination systems of either example shown in the Figures, towards the area (home or office environment) where the illumination system is installed, the ion generating source can be provided or interact with an air fan device 50. The implementation of such fan 50 is depicted in Figure 8, showing the fan 50 in a compartment forming a non-contacting tubular shaped duct 41. However, such fan 50 can also be implemented in a contacting tubular shaped duct 41 as shown in Figures 5-6-7 and alternatively, such fan 50 can be disposed near each ion generating 40 of the duct-less example of Figure 1.

The alternative examples of the compartments are shown in Figure 9 and 10. In these examples, the space between the support structure 10 and the light emission window 20 is divided in at least one compartment 60 by means of compartment walls 60a-60b, with the at least one compartment 60 containing or accommodating at least one ion generating source 40. As such, in these examples no tubular shaped ducts 41 as in Figures 2-8 are used, simplifying the construction and also providing more room in the compartment 60 formed for accommodating additional components such as a fan 50 or for example one or more light emitting sources 30.

As to the volume V _CO mp of the compartment 60 with respect to the total volume Vtotai of the illumination systems shown in Figure 9 and 10 it is noted that the volume of the compartment V _CO mp is preferably < 30% of Vtotai, more preferably V _CO mp < 20% Vtotai, and most preferably V _CO mp < 20% Vtotai. A smaller volume of the compartment 60 will promote an improved exiting of the ionized air ions through the light emission window 20.

For an optimal operation of the air fan 50 in either example shown in this disclosure, proper air circulation through the compartment 60 or the duct 41 has to be guaranteed. Therefor the illumination system can be provided with at least one air inlet and at least one air out let, wherein the air out let is (at least part of) the light emission window 20 and the at least one air inlet can be provided at location different from the light emission window 20, e.g. at the backside of the illumination system or in the support structure 10.

In a similar manner as with the example of the tubular shaped duct 41, the compartment walls 60a-60b extend with their first wall ends 60al-60bl from the support structure 10 towards the light emission window 20. Preferably, the compartment wall 60a- 60b are mounted with their first wall ends 60al-60bl to the support structure 10 and with their second wall ends 60a2-60b2 to the light emission window 20 in a similar manner as the tubular shaped duct 41’ of the example shown in Figure 7. In that example the compartment walls 60a-60b are manufactured from the same or similar flexible material as that of the tubular shaped duct 41 of the example shown in Figure 7, allowing a temporarily bending or bulging due to a displacement of the light emission window 20 for example due to wind circulation or due to manipulation of the light emission window 20 by people. Figure 10 depicts yet another example, which can be implemented with the other examples depicted in Figures 1-9. Similar as in Figure 9, the illumination system 108 is provided with at least one compartment 60 in the space between the support structure 10 and the light emission window 20, the compartment 60 being formed by compartment wall 60a- 60b extending from the support structure 10 towards the light emission window 20. The functionality of the compartment wall 60a-60b have been described in relation to the example of Figure 9, but also apply for the example of Figure 10.

In an example, one of the compartment walls for example compartment wall 60b in Figure 9 can be manufactured from a material which is transmissive for the ionized molecules emitted in air by the ion generating source 40 in the compartment, thus improving the exiting of these ionized molecules towards the area in which the illumination system is installed.

The illumination system 108 further comprises at least one sensor 71, which in this example is contained in the compartment and near the ion generating source 40 and the fan 50. The sensor 71 serves to detect a level of ionized molecules emitted in air by the ion generating source 40 in the compartment.

A control device 70 is also provided in the illumination system 108 and received a signal from the sensor 71 corresponding with the detected level of ionized molecules emitted in air. The control device 70 controls the ion generating source 40, such as shutting off, starting on, or changing the emittance rate of ionized molecules of the ion generating source 40, as well as the fan 50 (shutting off, starting on, changing the fanning rate) in response to the signal received from the sensor 71 (and thus in response to the level of ionized molecules emitted in air being detected).

It is noted, that unlike the example of Figure 10, the sensor 71 as well as the control device 70 can also be mounted freely and near at least one ion generating source 40 in the space between the support structure 10 and the light emission window 20 of any of the examples of Figures 1-8.

As shown in all examples of the Figures 1-10 the support structure 10 and the light emission window 20 are essentially co-planer.

Additionally, in all examples of the Figures 1-10, in order to enhance the transmittance of the ionized air molecules through the porous the light emission window 20, the light emission window 20 is to be grounded with earth potential. If the light emission window 20 is not grounded but for example has a negative potential charge any negative air molecules produced by the ion generating source 40 will be repelled. This will result in a lower level of negative ion levels in the room, which will adversely affect the air treatment functionality of the illumination system.