Lighting devices for lighting and disinfection lighting

Abstract

The lighting device 100 includes a first solid-state light source 110 configured to emit visible light, at least one second solid-state light source 130 configured to emit a second light, at least one of violet light and ultraviolet (UV) light, a reflector 140 including at least one light reflecting surface 145, the reflector at least partially surrounding the first solid-state light source and the second solid-state light source, at least a portion of the reflector defining a mixing chamber 150 for mixing the visible light and the second light, a light exit window 160 configured to allow the visible light and the second light mixed by the mixing chamber to exit the lighting device through the light exit window, and a third solid-state light source 170 configured to emit UV light, the third solid-state light source 170 disposed outside the mixing chamber.

Description

[Technical field]

[0001] The present invention relates generally to a lighting device, and more particularly to a lighting device configured to provide a combination of desired illumination and disinfecting (germicidal) lighting effects. [Background technology]

[0002] As the demand for sterilization increases, disinfection lighting has become a hot topic again. For example, the use of deep UV-C light with a wavelength between 200nm and 230nm is currently being considered for use in living spaces. UV-C light with a wavelength between 200nm and 230nm can exert a sterilizing effect by inactivating viruses and killing bacteria. In addition, UV light with a wavelength between 200nm and 230nm has a shallow penetration depth into skin and eye tissues, thus preventing the light from causing harm to humans.

[0003] Moreover, it is interesting to combine the advantageous properties of disinfection lighting with the desirable properties of general lighting devices. It will be understood that an important property for many lighting devices is that the lighting device is configured to provide uniform illumination. Another important aspect of lighting devices is the increasing need to provide energy efficiency during operation. Solid-state light sources such as light-emitting diodes (LEDs) for lighting purposes continue to attract attention by offering many advantages such as longer operating life, reduced power consumption, and improved efficiency in terms of the ratio between light energy and heat energy compared to incandescent lamps, fluorescent lamps, neon tube lamps, etc. However, since LEDs are point sources, there is a problem of producing LED-based lighting devices that provide uniform illumination.

[0004] EP3336417A1 discloses an illumination system that combines an array of UV LEDs facing a light exit window with an array of visible LEDs facing a reflector arrangement. Reflection can be used to provide the desired beam shaping or diffusion so that no beam shaping components are required at the exit window.

[0005] US10413626B discloses a multi-light emitter device for inactivating microorganisms. The device includes a blue light emitter and a violet light emitter. A light conversion material is configured to convert at least a portion of the light from the light emitters. Any unconverted light emitted from the light emitters and the converted light emitted from at least one light conversion material mix to form a composite light, the composite light being white.

[0006] Therefore, it is desirable to provide a lighting device that can provide desired illumination in terms of lighting and / or energy efficiency wants or requirements, and further, can provide disinfecting or sterilizing lighting effects during operation. Summary of the Invention [Problem to be solved by the invention]

[0007] It is an object of the present invention to provide a lighting device that can provide desired lighting in terms of lighting and / or energy efficiency needs or requirements, and furthermore can provide a disinfecting or sterilizing lighting effect during operation. [Means for solving the problem]

[0008] This and other objects are achieved by providing a lighting device having the features of the independent claims. Preferred embodiments are defined in the dependent claims.

[0009] Therefore, according to the present invention, there is provided a lighting device comprising at least one first solid-state light source configured to emit visible light in a wavelength range of 430 nm to 800 nm and at least one second solid-state light source configured to emit a second light of at least one of violet light and ultraviolet (UV) light in a wavelength range of 315 nm to 420 nm. The lighting device further comprises a reflector including at least one light reflecting surface, the reflector at least partially surrounding the at least one first solid-state light source and the at least one second solid-state light source. At least a portion of the reflector defines a mixing chamber for mixing at least a portion of the visible light emitted from the at least one first solid-state light source and at least a portion of the second light emitted from the at least one second solid-state light source. The lighting device further comprises a light exit window, the light exit window configured to allow the visible light and the second light mixed by the mixing chamber to exit the lighting device through the light exit window. The illumination device further comprises at least one third solid-state light source configured to emit UV light in a wavelength range from 190 nm to 315 nm, the at least one third solid-state light source disposed outside the mixing chamber.

[0010] The (spectral power distribution of) the at least one third solid-state light source is different from the (spectral power distribution of) the at least one second solid-state light source.

[0011] The present invention is therefore based on the idea of ​​providing combined illumination and disinfection illumination by means of a lighting device configured to emit visible light for illumination purposes and violet and / or UV light for disinfection purposes. By mixing visible light and violet and / or UV light in the mixing chamber for subsequent transmission through the light exit window and emitting UV light from one or more positions outside the mixing chamber, the lighting device can thereby meet illumination needs and / or desires while at the same time providing illumination with disinfecting or germicidal effects.

[0012] The present invention is advantageous in that the lighting device provides space illumination and disinfection with high efficiency and / or low cost and / or long life. The violet and / or UV light emitted from the second solid-state light source is optimally distributed and / or delivered through the relatively large light exit window. Furthermore, the mixing chamber defined by at least a portion of the reflector is generally (more) sensitive to lower UV wavelengths, i.e., UV wavelengths lower than the wavelengths of the violet and / or UV light emitted from the second solid-state light source, which may lead to degradation of materials used in the mixing chamber.

[0013] The present invention is advantageous in that the lighting device is able to achieve a very high degree of mixing of light via its mixing chamber defined by at least a part of the reflector before it exits through the light exit window. More specifically, the light reflecting surface of the reflector ensures that almost all of the light emitted towards it is reflected and eventually coupled out of the light exit window.

[0014] The present invention is further advantageous by the possibility of providing the second solid-state light source with different characteristics to the third solid-state light source to provide a lighting device that meets the desired effect of the disinfection lighting while at the same time being cost-effective. For example, the second solid-state light source may be relatively inexpensive and may have relatively high efficiency, while the third solid-state light source may be relatively expensive and may have relatively low efficiency.

[0015] The present invention is further advantageous in that the lighting device may provide the violet and / or UV light according to a required and / or desired emission, for example the lighting device may be configured to direct the violet and / or UV light to specific areas, for example in a room, where a disinfecting effect is particularly desirable or required.

[0016] The present invention is further advantageous in that the ability of the lighting device to provide a mixture of visible and violet and / or UV light from the mixing chamber, and UV light from a location outside the mixing chamber, results in an aesthetically pleasing lighting device when in operation, and further, an observer viewing the lighting device may perceive the UV light from a location outside the mixing chamber.

[0017] The present invention is further advantageous in that the lighting device of the present invention has relatively few components, which is advantageous in that the lighting device is relatively cheap to manufacture. Furthermore, the fewer components of the lighting device means easier recycling, especially compared to devices or apparatuses that include a relatively large number of components that impede easy disassembly and / or recycling operations.

[0018] The lighting device comprises at least one first solid-state light source. The term "solid-state light source" (SSL light source) herein means a light source using one or more semiconductor diodes. For example, a solid-state light source may include light emitting diodes (LEDs), organic light emitting diodes (OLEDs), polymer light emitting diodes (PLEDs), laser diodes, superluminescent diodes, etc. as illumination sources. The first solid-state light source is configured to emit visible light. The term "visible light" herein means light within a wavelength range of 430-800 nm that can be perceived by the human eye. The lighting device further comprises at least one second solid-state light source configured to emit a second light of at least one of violet light and ultraviolet (UV) light within a wavelength range of 315 nm to 420 nm. The term "violet light" herein means light within a wavelength range of 380-450 nm, which is at the higher end of the visible spectrum, and the term "ultraviolet light" herein means light within a wavelength range of 100-400 nm. Therefore, according to the invention, the at least one second solid-state light source is configured to emit a second light of violet and / or UV light in the wavelength range from 315 nm to 420 nm.

[0019] The lighting device further comprises a reflector including at least one light reflecting surface. The term "reflector" herein means substantially any element, structure, device, etc., configured to reflect incident light. The reflector at least partially surrounds the at least one first solid-state light source and the at least one second solid-state light source. In other words, the first and second solid-state light sources are at least partially surrounded by the reflector such that the reflector is configured to reflect incident light from the first and second solid-state light sources during operation. The reflector defines a mixing chamber for mixing at least a portion of the visible light emitted from the at least one first solid-state light source. In other words, the reflector can mix the light emitted from the first solid-state light source in the mixing chamber via the light reflecting surface of the reflector.

[0020] The lighting device further comprises a light exit window. The term "light exit window" here means a material (e.g. glass) through which light can exit. The visible light and the violet and / or UV light mixed by the mixing chamber are configured to exit the lighting device through the light exit window. In other words, the light exit window is configured to couple out the mixed light.

[0021] The lighting device further comprises at least one third solid-state light source configured to emit UV light in a wavelength range of 190 nm to 315 nm, the at least one third solid-state light source being disposed outside the mixing chamber, in other words, the third solid-state light source is provided on or in the lighting device, but is not disposed within the mixing chamber as defined by at least a portion of the reflector.

[0022] According to an embodiment of the present invention, the at least one third solid-state light source may be arranged in a portion of the reflector, such that the third solid-state light source is arranged outside the mixing chamber, such that the third solid-state light source is arranged in a part or portions of the reflector that do not define the mixing chamber.

[0023] According to an embodiment of the present invention, the at least one third solid-state light source may be configured to emit UV light in the wavelength range from 280 nm to 315 nm. Thus, the third solid-state light source may be configured to emit ultraviolet B (UV-B) light.

[0024] According to an embodiment of the present invention, the at least one third solid-state light source may be configured to emit UV light within a wavelength range of 190 nm to 230 nm. Since ultraviolet C (UV-C) light may be defined as light within a wavelength range of 100 to 280 nm, the third solid-state light source may thus be configured to emit light within a wavelength subrange of UV-C light. In another example, the at least one third solid-state light source may be configured to emit light within a wavelength range of 230 to 280 nm, which light may be classified or considered as "near UV-C light".

[0025] According to an embodiment of the invention, the at least one third solid-state light source may be configured to emit violet light in the wavelength range of 190 nm to 230 nm. Since violet light may be defined as light in the wavelength range of 100 to 280 nm, the third solid-state light source may thus be configured to emit light in a wavelength sub-range of UV-C light.

[0026] According to an embodiment of the present invention, the light exit window may be a diffuser having a reflectance in the range of 30% to 80% for the visible light. The term "diffuser" here means substantially any element, material, etc., arranged to diffuse the light incident on it. Since the light exit window in the form of a diffuser has a reflectance in the range of 30% to 80% for the visible light, the light exit window is partially reflective, i.e. semi-reflective. Thus, the light exit window according to the embodiment is advantageous in that a part of the light incident on the light exit window is reflected back into the mixing chamber, resulting in an even more improved light mixing in the mixing chamber before the visible light leaves the lighting device.

[0027] According to an embodiment of the present invention, the light exit window may comprise at least one optical element configured to diffract, refract and / or diffuse the visible light and the second light mixed by the mixing chamber. The term "optical component" here means substantially any component, element etc. configured or arranged to influence, guide and / or act on light via diffraction, refraction and / or diffusion. This embodiment is advantageous in that the optical component can influence the light coupled out of the exit window to meet the illumination and / or germicidal illumination requirements and / or demands of the lighting device.

[0028] According to an embodiment of the invention, the at least one first solid-state light source and the at least one second solid-state light source may be arranged at a base portion of the reflector, the base portion being arranged opposite the light exit window. This embodiment is advantageous in that this position of the first and second solid-state light sources may result in even greater mixing of light in the mixing chamber before the light exits through the light exit window.

[0029] According to an embodiment of the present invention, the number N1 of the at least one second solid-state light source and the number N2 of the at least one third solid-state light source may satisfy N1>2·N2. Therefore, the number of the second solid-state light sources disposed within the mixing chamber may be significantly greater than the number of the third solid-state light sources disposed outside the mixing chamber.

[0030] According to an embodiment of the present invention, the at least one third solid-state light source may comprise a plurality of light sources, each third solid-state light source may be configured to emit light away from the light exit window, and at least a first third solid-state light source may be configured to emit light in at least a first direction, and at least a second third solid-state light source may be configured to emit light in at least a second direction, the at least one first direction being different from the at least one second direction. Thus, each third solid-state light source of the plurality of third solid-state light sources may be configured to emit light in a respective direction away from the light exit window, i.e. in a direction such that light does not strike the light exit window. Furthermore, each third solid-state light source of the plurality of third solid-state light sources may be configured to emit light in a unique respective direction such that two different light beams or directions of light do not intersect or cross.

[0031] According to an embodiment of the present invention, the light exit window may be non-transparent to the UV light emitted from the at least one third solid-state light source, and thus may be configured to block the UV light emitted from the third solid-state light source.

[0032] The lighting device further comprises a controller configured to individually control the at least one second solid-state light source and the at least one third solid-state light source. Thus, the controller may be configured to control the operation of each of the second solid-state light source and / or the third solid-state light source. For example, the controller may be configured to control one or more characteristics, such as intensity or spectral power distribution, of the light emitted from the second solid-state light source and / or the third solid-state light source. As a result, the relative amount of light from the second solid-state light source and the third solid-state light source may be varied to modify or further optimize the disinfecting properties of the lighting device, for example, depending on the type of pathogens targeted to be inactivated.

[0033] According to an embodiment of the present invention, the at least one third solid-state light source may be disposed at the light exit window.

[0034] According to an embodiment of the present invention, there is provided a lighting device comprising a lighting arrangement according to any one of the previous embodiments, the lighting device further comprising a housing at least partially enclosing the lighting arrangement, the at least one third solid-state light source being at least partially disposed within the housing.

[0035] According to an embodiment of the invention, the lighting device is one of a Light Emitting Diode (LED) device and a LED tube (T-LED).

[0036] According to an embodiment of the present invention, there is provided a luminaire comprising a lighting apparatus or lighting device according to any one of the previous embodiments, said lighting apparatus further comprising an electrical connection connected to said lighting apparatus for supplying electrical power to said at least one first solid-state light source, said at least one second solid-state light source and said at least one third solid-state light source of said lighting apparatus.

[0037] Other objects, features, and advantages of the present invention will become apparent upon study of the following detailed disclosure, drawings, and appended claims. Those skilled in the art will appreciate that different features of the present invention may be combined to create embodiments other than those described below. [Brief description of the drawings]

[0038] This and other aspects of the invention will now be described in more detail with reference to the accompanying drawings, in which embodiments of the invention are shown. [Figure 1] 1 illustrates a schematic diagram of a lighting device according to an exemplary embodiment of the present invention; [Diagram 2] 1 illustrates a schematic cross-section of a lighting device according to an exemplary embodiment of the invention; [Diagram 3] 1 illustrates a schematic cross-section of a lighting device according to an exemplary embodiment of the invention; [Figure 4a] 1 illustrates a schematic representation of an illumination device comprising an illumination apparatus according to an exemplary embodiment of the invention; [Figure 4b] 1 illustrates a schematic representation of an illumination device comprising an illumination apparatus according to an exemplary embodiment of the invention; [Diagram 5] 1 illustrates a schematic representation of a luminaire comprising a lighting device according to an exemplary embodiment of the invention; DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0039] FIG. 1 shows a schematic diagram of a lighting device 100 according to an exemplary embodiment of the present invention. The lighting device 100 includes a plurality of first solid-state light sources 110, which may include, for example, one or more light-emitting diodes (LEDs). The first solid-state light sources 110 are configured to emit visible light in a wavelength range of 430 nm to 800 nm. The visible light may be white light. The white light may have a color temperature (CT) in a range of 2000 K to 6000 K. The white light may have a color rendering index (CRI) of at least 80. The CRI R9 of the white light may be >0. The white light may have a color point within 15 SDCM, such as within 7 SDCM, such as within 10 SDCM, from the black body locus (BBL). The first solid-state light source 110 may be one or more white solid-state light sources, such as one or more white LEDs.

[0040] It should be noted that while multiple first solid-state light sources 110 are shown in this example, the lighting device 100 may have a single first solid-state light source 110. Additionally, the positioning of the first solid-state light source 110 in the lighting device 100 may differ from that shown.

[0041] The lighting device 100 further comprises a second solid-state light source 130 configured to emit violet light and / or UV light within a wavelength range of 315 nm to 420 nm. It should be noted that the aforementioned wavelength range of 315 nm to 420 nm may include a first wavelength sub-range of 315 to 380 nm (UV-A light) and a second wavelength sub-range of 380 to 420 nm (violet light). It should be noted that in this example, the lighting device 100 only includes a single second solid-state light source 130, but the lighting device 100 may have any number of second solid-state light sources 130. The second solid-state light source 130 may be, for example, an LED, a laser diode, or a superluminescent diode.

[0042] The lighting device 100 further comprises a reflector 140 at least partially surrounding the first solid-state light source 110 and the second solid-state light source 130. The first solid-state light source 110 and the second solid-state light source 130 are disposed on a base portion 210 of the reflector 140. The reflector 140 further comprises one or more light-reflecting surfaces 145. Here, the light-reflecting surfaces 145 are defined as circumferential side walls, which according to this example have a circular cross-section taken in a plane parallel to the base portion 120. Thus, in this exemplary embodiment of the lighting device 100, the base portion 210 of the reflector 140 and the reflective surfaces 125 define a cylindrical shape of the reflector 140.

[0043] The lighting device 100 further comprises a light exit window 160 arranged opposite the base 210 of the reflector 140. It should be noted that in Fig. 1 the light exit window 160 is merely indicated by a dashed line representation at its outer contour for reasons of visibility of (other) parts and components of the lighting device 100. The light exit window 160 may be, for example, a plate or a disk. The visible light emitted from the first solid-state light source 110 and the violet and / or UV light emitted from the second solid-state light source 130 are configured to be mixed in a mixing chamber 150 defined by at least a part of the reflector 140 and to exit the lighting device 100 through the light exit window 160.

[0044] In the following, embodiments and examples of a mixing chamber 150 defined by at least a portion of the reflector 140 of the lighting device 100 are provided, whereas in Figures 2 to 4 further embodiments and examples of the lighting device 100 are provided.

[0045] The mixing chamber 150 as defined by at least a portion of the reflector 140 of the lighting device 100 as illustrated in FIG. 1 has a width (W) and a height (H). The height (H) of the mixing chamber 150 is defined as the height of the light reflecting surface 145 in the form of a peripheral side wall. This height (H) of the mixing chamber 150 for the embodiment shown in FIG. 1 can also be interpreted as the distance between the base portion 210 and the light exit window 160. The width (W) of the mixing chamber 150 is defined as having a base surface extension that is the minimum distance between two opposite points on the periphery of the surface of the base portion 210. In the embodiment shown in FIG. 1, the width (W) of the mixing chamber 150 is the diameter of the base portion 120. An aspect ratio of the width (W) and height (H) of the mixing chamber 150 in the range of 1 to 8 can improve the light mixing of the reflector 140 while the efficiency of the lighting device 100 does not decrease beyond an acceptable range. Tests were conducted to evaluate the efficiency and uniformity of light coupled out of the lighting device 100 as a function of the aspect ratio. These tests were conducted with a mixing chamber 150 having a width (W) (i.e., diameter) of 150 mm, the reflectivity of the light exit window 160 was kept at 50%, and the height (H) of the mixing chamber 150 was varied between 10 mm and 50 mm. The first solid-state light source 100 was placed adjacent to the base portion 120. The tests show that the contrast, which is the ratio of the maximum intensity to the minimum intensity of the light emitted from the lighting device 100, drops rapidly from 18 to 2 when the height (H) is increased from 10 mm to 20 mm (i.e., the aspect ratio is decreased from 15 to 7.5). When the height (H) is increased from 20 to 45, the contrast drops from 2.0 to 1.7. Furthermore, tests show that when the height (H) is increased from 15 mm to 50 mm, the efficiency decreases approximately linearly from 96.0% to 94.5%.

[0046] According to the example of the lighting device 100 in FIG. 1, the base part 120 has an inner surface with high reflectivity, i.e., reflectivity in the range of 90% to 100%, for the visible light emitted by the first solid-state light source 110. Furthermore, the absorbance of the base part 120 is close to zero for the light emitted from the first solid-state light source 110. It will be understood that the absorbance close to zero results in high efficiency of the lighting device 100. The base part 120 can be made of metal or glass. The base part 120 can be covered by, for example, a sheet of reflective material or painted with a coating reflector. The sheet of reflective material can be MCPET foil. The coating reflector can be, for example, TiO2 powder particles mixed with transparent silicone. Instead of TiO2 powder, Al2O3 powder and / or BaSO4 powder can be used and mixed with transparent silicone.

[0047] The light reflecting surface 145 has an inner surface with high reflectivity, i.e., reflectivity in the range of 90% to 100%, for the visible light emitted by the first solid-state light source. Furthermore, the light absorbance of the light reflecting surface 145 is close to zero for the light emitted from the first solid-state light source 110. It will be appreciated that the close to zero absorbance results in high efficiency of the lighting device 100.

[0048] The light reflecting surface 145, like the inner surface of the base portion 120, may be covered by a sheet of reflective material or painted with a coating reflector. The base portion 120 and the light reflecting surface 145 may be manufactured to be as white as possible, which may minimize light absorption in the mixing chamber 150.

[0049] The light exit window 160 of the lighting device 100 is semi-reflective. More specifically, the reflectance of the light exit window 160 is in the range of 30% to 80% for the light emitted from the first solid-state light source 110. The absorbance of the light exit window 160 is preferably less than 2% for the light emitted from the first solid-state light source 110. Having such a low absorbance in the light exit window 160 results in a high efficiency of the lighting device 100. As a non-limiting example, the light exit window 160 may be made of Makrofol®. However, other materials such as Lexan®, MB-grades, Lexalite Lumieo® and Flexi-Lume® may also be used. TiO in a polymer such as silicone rubber. x or AlO x It is also possible to use a layer of scattering particles such as , and adjust the reflectance by the concentration of the particles and / or the thickness of the layer.

[0050] The light exit window 160 may have at least one optical element (not shown) configured to diffract, refract, and / or diffuse the visible light emitted by the first solid-state light source 110 and the second light emitted by the second solid-state light source 130 that are mixed by the mixing chamber.

[0051] The light exit window 160 may further comprise a luminescent material that may convert at least a portion of the light of a first color that strikes the luminescent material of the light exit window 160 into light of a second color.

[0052] The first solid-state light source 110 of the lighting device is configured to emit visible light in the wavelength range of 430 nm to 800 nm. For example, one or more of the first solid-state light sources 110 may be configured to emit white light.

[0053] According to another example, one or more of the first solid-state light sources 110 may be configured to emit light of a particular color. For example, at least one of the first solid-state light sources 110 may be configured to emit red light, at least one of the first solid-state light sources 110 may be configured to emit green light, and at least one of the first solid-state light sources 110 may be configured to emit blue light. According to another example, one or more of the first solid-state light sources 110 may be configured to emit blue light. In such a case, the light exit window 160 preferably has a luminescent material that converts a portion of the blue light that strikes the luminescent material into light of another color.

[0054] FIG. 2 is a schematic cross-sectional view of a lighting device 100 according to an exemplary embodiment of the present invention. It should be noted that the lighting device 100 illustrated in FIG. 2 may constitute the lighting device 100 illustrated in FIG. 1, and reference should be made to FIG. 1 and the associated text for a better understanding of the features and / or components of the lighting device 100 in FIG. 2. The lighting device 100 has at least one first solid-state light source 110 configured to emit visible light within a wavelength range of 430 nm to 800 nm. The lighting device 100 further has at least one second solid-state light source 130 configured to emit violet light and / or UV light within a wavelength range of 315 nm to 420 nm. Although the first solid-state light source 110 and the second solid-state light source 130 are each illustrated as a single light source, it will be understood that the number of the first solid-state light source 110 and the second solid-state light source 130 may be any number.

[0055] The lighting device 100 in Fig. 2 further comprises a reflector 140 including at least one light reflecting surface 145 as previously described in relation to Fig. 1. The reflector 140 at least partially surrounds the first solid-state light source 110 and the second solid-state light source 130. The reflector 140 defines a mixing chamber 150 for mixing at least a portion of the visible light emitted from the at least one first solid-state light source 110 and at least a portion of the second light (i.e., purple light and / or UV light) emitted from the at least one second solid-state light source 130.

[0056] 2 further comprises a light exit window 160. The light mixed by the mixing chamber 150 is configured to exit the lighting device 100 through the light exit window 160.

[0057] The lighting device 100 in FIG. 2 further includes at least one third solid-state light source 170 configured to emit UV light in the wavelength range of 190 nm to 315 nm. Thus, the third solid-state light source is configured to emit UV-B and / or UV-C light in the wavelength range of 190 to 315 nm. In this example, the lighting device 100 includes only a single third solid-state light source 170, but it should be noted that the lighting device 100 may have any number of third solid-state light sources 170. For example, the number N1 of the second solid-state light sources 130 and the number N2 of the third solid-state light sources 170 may satisfy N1>2·N2, such as N1>3·N2 or N1>5·N2.

[0058] The third solid-state light source 170 is disposed outside the mixing chamber 150 as defined by at least a portion of the reflector 140 of the lighting device 100. In this example, the third solid-state light source 170 is provided in a part or portion 190 of the reflector 140 that does not define the mixing chamber 150. Thus, the third solid-state light source 170 is disposed in a part or portion 190 of the reflector 140 outside the mixing chamber 150. Thus, the light emitted from the third solid-state light source 170 is not coupled out by the light exit window 160. Furthermore, the light emitted from the third solid-state light source 170 is configured not to collide with the light exit window 160. Also, the light exit window 160 may be non-transparent to the UV light emitted from the third solid-state light source 170.

[0059] FIG. 3 shows a schematic cross-section of a lighting device 100 according to an exemplary embodiment of the present invention. It is noted that the lighting device 100 illustrated in FIG. 3 may constitute the lighting device 100 illustrated in FIG. 1 or FIG. 2, and reference is made to FIG. 1 and / or FIG. 2 and the associated text for a better understanding of the features and / or components of the lighting device 100 in FIG. 3. In FIG. 3, the lighting device has a first third solid-state light source 170a and a second third solid-state light source 170b, each disposed on a part or portion 190 of the reflector 140 outside the mixing chamber 150. However, it is noted that the lighting device 100 may have any number of third solid-state light sources. According to this example, each third solid-state light source 170a, 170b may be configured to emit light away from the light exit window 160, as indicated by the schematic illustrated first and second (beam) directions (D1, D2) of light emitted from the respective first and second third solid-state light sources 170a, 170b. Furthermore, the first third solid-state light source 170a may be configured to emit light in a first direction (D1) and the second third solid-state light source 170b may be configured to emit light in a second direction (D2), the first direction (D1) being different from the second direction (D2). Thus, the first and second third solid-state light source 170a, 170b may be configured to emit light in respective directions (D1, D2) away from the light exit window 160, i.e. in directions such that light from each of the first and second third solid-state light source 170a, 170b does not strike the light exit window 160. Furthermore, the first and second third solid-state light source 170a, 170b may be configured to emit light in unique, respective directions such that two different light beams or directions of light do not intersect or cross, e.g. as illustrated by the schematic first and second (beam) directions (D1, D2).

[0060] 4a and 4b show a schematic view of a lighting device 300 according to an example of the present invention. The lighting devices 300 each include a lighting device 100 according to any one of the above-mentioned embodiments, and further include a housing 310. It will be understood that the housing 310 may have different structures or shapes depending on the type of the lighting device 300. The housing 310 at least partially surrounds the lighting device 100, and at least one third solid-state light source 170 is at least partially disposed within the housing 310. According to the example of the lighting device 300 in FIG. 4a, the lighting device 300 constitutes an LED device, such as an LED lamp. According to the example of the lighting device 300 in FIG. 4b, the lighting device 300 constitutes an LED tube (T-LED).

[0061] FIG. 5 shows a schematic diagram of a lighting fixture 500 having one or more lighting devices 100 according to an exemplary embodiment of the present invention. The lighting fixture 500 may be arranged, for example, in a ceiling of a hallway, a room, etc. It will be understood that the lighting fixture 500 may take a different shape and / or structure than that shown in FIG. 5, and the lighting fixture 500 shows an example. The lighting fixture 500 has electrical connections connected to the lighting device 100 for supplying power to at least one first and second solid-state light source (not shown) of the lighting device 100 and to a third solid-state light source 170. The lighting device 100 as illustrated has three third solid-state light sources 170 configured to emit UV light in the wavelength range from 190 nm to 315 nm. It is noted that one or more of the third solid-state light sources 170 may be arranged in the light exit window 160 (not shown). A first solid-state light source configured to emit visible light in the wavelength range of 430 nm to 800 nm, and a second solid-state light source configured to emit a second light of at least one of violet light and ultraviolet (UV) light in the wavelength range of 315 nm to 420 nm, are provided behind the light exit window 160 and are therefore not shown in FIG. 5.

[0062] It will be understood that the wavelength range of UV light can be defined in the range of 100 nm to 380 nm and can be divided into different types of UV light / UV wavelength ranges (Table 1). Different UV wavelengths of radiation may have different characteristics and therefore may have different compatibility with human presence and different effectiveness when used for disinfection (Table 1). [Table 1]

[0063] It should be noted that each UV type / wavelength range may have different advantages and / or disadvantages. Relevant aspects may be (relative) germicidal effectiveness, safety (regarding radiation), and ozone generation (as a result of its radiation). Depending on the application, a particular type of UV light, or a particular combination of types of UV light, may be selected to perform better than other types of UV light. UV-A may be (relatively) safe, may kill bacteria, but may be less effective at killing viruses. UV-B may be (relatively) safe if low doses (i.e. low exposure times and / or low intensity) are used, may kill bacteria, and may be moderately effective at killing viruses. UV-B may also have the additional advantage that it can be effectively used in the production of Vitamin D in human or animal skin. Near-UV-C may be relatively dangerous, but may effectively kill bacteria and viruses. Far UV may also be effective in killing bacteria and viruses, but may be (rather) safe (relative to other UV-C wavelength ranges). Far UV light may generate some ozone that may be harmful to humans and animals. Extreme UV-C may also be effective in killing bacteria and viruses, but may be relatively dangerous. Extreme UV-C may generate ozone that may be undesirable if exposed to humans or animals. In some applications, ozone may be desirable and may contribute to disinfection, but in those cases, its shielding from humans and animals may be desired. Thus, a "+" for ozone generation in the table means that ozone is generated that may be useful, particularly for disinfection applications, but may be harmful to humans / animals if they are exposed to it. Thus, this "+" may actually be undesirable in many applications, but may be desirable in others.

[0064] Those skilled in the art will appreciate that the present invention is in no way limited to the above-described preferred embodiment. On the contrary, many modifications and variations are possible within the scope of the appended claims. For example, one or more of the first solid-state light source 110, the second solid-state light source 130, and / or the third solid-state light source 170, the reflector 140, etc. may have different shapes, dimensions, and / or sizes than those shown / described.

Claims

1. 1. A lighting device, comprising: at least one first solid-state light source configured to emit visible light within a wavelength range of 430 nm to 800 nm; at least one second solid-state light source configured to emit a second light of at least one of violet light and UV light in a wavelength range of 315 nm to 420 nm; a reflector including at least one light reflecting surface, the reflector at least partially surrounding the at least one first solid-state light source and the at least one second solid-state light source, at least a portion of the reflector defining a mixing chamber for mixing at least a portion of the visible light emitted from the at least one first solid-state light source and at least a portion of the second light emitted from the at least one second solid-state light source; a light exit window configured to allow the visible light and the second light mixed by the mixing chamber to exit the lighting device through the light exit window; at least one third solid-state light source configured to emit UV light in a wavelength range of 190 nm to 315 nm, the at least one third solid-state light source disposed outside the mixing chamber; a controller configured to individually control the at least one second solid-state light source and the at least one third solid-state light source, the controller further configured to control one or more characteristics of light emitted from the second solid-state light source and / or the third solid-state light source.

2. The lighting device of claim 1 , wherein the at least one third solid-state light source is disposed in a portion of the reflector.

3. 3. The lighting device according to claim 1 or 2, wherein the at least one third solid-state light source is configured to emit UV light in the wavelength range from 280 nm to 315 nm.

4. 3. The lighting device according to claim 1 or 2, wherein the at least one third solid-state light source is configured to emit UV light in the wavelength range from 190 nm to 230 nm.

5. 4. The illumination device according to claim 1, wherein the light exit window is a diffuser having a reflectance for the visible light in the range of 30% to 80%.

6. 4. The illumination device according to claim 1, wherein the light exit window comprises at least one optical element configured to diffract, refract and / or diffuse the visible light and the second light mixed by the mixing chamber.

7. 4. The lighting device according to claim 1, wherein at least one of the at least one first solid-state light source and the at least one second solid-state light source is disposed on a base portion of the reflector, the base portion being disposed opposite the light exit window.

8. The number N of the at least one second solid-state light source １ and the number N of the at least one third solid-state light source. ２ But, N １ >2.N ２ The lighting device according to claim 1 , wherein the above-mentioned condition is satisfied.

9. 4. The lighting device according to claim 1, wherein the at least one third solid-state light source comprises a plurality of light sources, each third solid-state light source being configured to emit light away from the light exit window, at least a first third solid-state light source being configured to emit light in at least a first direction, and at least a second third solid-state light source being configured to emit light in at least a second direction, and the at least one first direction being different from the at least one second direction.

10. 4. The lighting device according to claim 1, wherein the light exit window (12) is non-transparent to the UV light emitted from the at least one third solid-state light source.

11. 4. The lighting device of claim 1, wherein the controller is configured to control one or more characteristics of the light emitted from the second solid-state light source and the third solid-state light source.

12. 4. The lighting device according to claim 1, wherein the at least one third solid-state light source (12) is arranged at the light exit window (12).

13. A lighting device according to any one of claims 1 to 3, a housing at least partially enclosing the lighting apparatus, The at least one third solid-state light source is at least partially disposed within the housing.

14. 14. The lighting device of claim 13, wherein the lighting device is one of an LED device and a T-LED.

15. At least one of the lighting apparatus according to claim 1 to 3 or the lighting device according to claim 13 or claim 14, and an electrical connection connected to the lighting device for supplying power to the at least one first solid-state light source, the at least one second solid-state light source, and the at least one third solid-state light source.

Images