A light generating system having less-intense broad-band blue emission

Abstract

The invention provides a light generating system (1000) comprising: (i) a first light generating device (110), (ii) a second light generating device (120), (iii) a third and / or fourth light generating device (130,140), and (iv) a control system (300), wherein: (A) the first light generating device (110) comprises a first luminescent converter (2100), and a first light source (10) to generate first light source light (11) having a first peak wavelength (λp1); (B) the first luminescent converter (2100) comprises a first luminescent material (210) to convert first light source light (11) into first luminescent material light (211); (C) the first light generating device (110) is configured to generate first device light (111) comprising first luminescent material light (211) and first light source light (11); (D) the second light generating device (120) comprises a second luminescent converter (2200), and a second light source (20) to generate second light source light (21) having a second peak wavelength (λp2); (E) the second luminescent converter (2200) comprises a second luminescent material (220) to convert second light source light (21) into second luminescent material light (221); (F) the second light generating device (120) is configured to generate second device light (121) comprising second luminescent material light (221) and second light source light (21); (G) the third light generating device (130) comprises a third luminescent converter (2300), and a third light source (30) to generate third light source light (31) having a third peak wavelength (λp3); (H) the third luminescent converter (2300) comprises a third luminescent material (230) to convert third light source light (31) into third luminescent material light (231); (I) the third light generating device (130) is configured to generate white third device light (131) comprising third luminescent material light (231) and third light source light (31); (J) the fourth light generating device (140) comprises a fourth light source (40) to generate fourth light source light (41) having a fourth peak wavelength (λp4); (K) the fourth light generating device (140) is configured to generate fourth device light (141) comprising fourth light source light (41); (L) λp1, λp2, λp3, and λp4 are selected from the range of 400-490 nm; wherein for at least three of λp1, λp2, λp3, and λp4 applies that they mutually differ by at least 15 nm; (M) the light generating system (1000) is configured to generate system light (1001) comprising one or more of the first, second, third, and fourth device light (111,121,131,141); and (N) the control system (300) is configured to control a spectral power distribution of the system light (1001) in the wavelength range of 380-780 nm.

Description

[0001] 2024PF80384

[0002] 1

[0003] A LIGHT GENERATING SYSTEM HAVING LESS-INTENSE BROAD-BAND BLUE EMISSION

[0004] FIELD OF THE INVENTION

[0005] The invention relates to a light generating system. The invention further relates to a lighting device comprising the light generating system.

[0006] BACKGROUND OF THE INVENTION

[0007] Light generating systems are known in the art. For instance, US2024120448A1 describes a red-light emitting device comprising: a blue LED chip; and a photoluminescence material comprising a narrowband red fluoride phosphor and a broadband red phosphor. The narrowband red phosphor may comprise a manganese-activated fluoride phosphor of composition K2SiF6:Mn4+, K2GeF6:Mn4+, and K2TiF6:Mn4+.

[0008] US2024332464A1 discloses a light emitting device comprising a first LED for generating a first light with a dominant wavelength from 620 nm to 640 nm and a FWHM of less than 55 nm; the first LED comprising a phosphor-converted LED comprising an LED for generating light with a dominant wavelength from 400 nm to 480 nm, and a narrowband red phosphor.

[0009] SUMMARY OF THE INVENTION

[0010] Conventional light generating systems (e.g. incandescent or fluorescent lamps) are rapidly being replaced by light emitting diode (LED) based lighting solutions. LED-based lighting solutions may generally comprise a light source and a luminescent converter, wherein the luminescent converter may comprise multiple types of phosphors, e.g. a yellow and a red phosphor, to produce especially white light with a suitable color temperature. Said white light may further comprise blue light emitted by the LED. In general, all LEDs in a lighting system may emit LED light having the same peak emission wavelength, selected from a wavelength range of 400-490 nm. However, said blue LED light may cause damage to photoreceptor cells and / or retinal pigment epithelial cells in the eye of an observer, especially when the blue LED light is present at relatively higher intensities (which may be the case for lighting systems providing “cool” white light, such as office lighting systems). One solution2024PF80384

[0011] 2

[0012] may be to reduce the intensity of the blue light in the system light. However, such solutions may reduce a CCT of the system light, leading to the generation of “warm” white light, which may be undesired in certain applications (e.g. in offices, supermarkets, hospitals, etc.). Alternatively, green LEDs may be used. However, the phosphors used in LED-based lighting solutions may be less efficient in converting green light compared to blue light, reducing the energy efficiency of the lighting system. Further, using green light may reduce the color gamut of the system light, such that the color point and / or correlated color temperature of the system light may be adjusted over a smaller range, which may reduce the versatility of the lighting system. Clearly, there is a need for a light generating system providing system light with a relatively large color gamut, while reducing the negative effects of high-intensity blue light. Hence, it is an aspect of the invention to provide an alternative light generating system, which preferably further at least partly obviates one or more of above-described drawbacks. The present invention may have as object to overcome or ameliorate at least one of the disadvantages of the prior art, or to provide a useful alternative.

[0013] According to a first aspect, the invention provides a light generating system comprising: (i) a first light generating device, (ii) a second light generating device, (iii) one or more of a third light generating device and a fourth light generating device, and (iv) a control system. The first light generating device may comprise a first solid state light source and a first luminescent converter. Especially, the first solid state light source may be configured to generate first light source light having a first peak emission wavelength (λp1) selected from the wavelength range of 380-500 nm, such as from the wavelength range of 400-490 nm. Further, the first luminescent converter may be configured in a light receiving relationship with the first solid state light source. The first luminescent converter may comprise a first luminescent material. Especially, the first luminescent material may be configured to convert part of the first light source light received by the first luminescent converter into first luminescent material light. In embodiments, the first luminescent material light may have a first centroid wavelength (λc1) selected from the wavelength range of 600-660 nm. The first light generating device may be configured to generate first device light. Especially, the first device light may comprise the first luminescent material light and part of the first light source light. The second light generating device may comprise a second solid state light source and a second luminescent converter. Especially, the second solid state light source may be configured to generate second light source light having a second peak emission wavelength (λp2) selected from the wavelength range of 380-500 nm, such as from the wavelength range of 400-490 nm. Further, the second luminescent converter may be2024PF80384

[0014] 3

[0015] configured in a light receiving relationship with the second solid state light source. The second luminescent converter may comprise a second luminescent material. Especially, the second luminescent material may be configured to convert part of the second light source light received by the second luminescent converter into second luminescent material light. In embodiments, the second luminescent material light may have a second centroid wavelength (λc2) selected from the wavelength range of 490-590 nm. The second light generating device may be configured to generate second device light. The second device light may especially comprise the second luminescent material light and part of the second light source light. The third light generating device may comprise a third solid state light source and a third luminescent converter. Especially, the third solid state light source may be configured to generate third light source light having a third peak emission wavelength (λp3) selected from the wavelength range of 380-500 nm, such as from the wavelength range of 400-490 nm. Further, the third luminescent converter may be configured in a light receiving relationship with the third solid state light source. The third luminescent converter may comprise a third luminescent material. Especially, the third luminescent material may be configured to convert part of the third light source light received by the third luminescent converter into third luminescent material light. The third light generating device may be configured to generate third device light. Especially, the third device light may comprise the third luminescent material light and part of the third light source light. Further, the third device light may be white light having a correlated color temperature selected from the range of 1700-8000 K. The fourth light generating device may comprise a fourth solid state light source. Especially, the fourth solid state light source may be configured to generate fourth light source light having a fourth peak emission wavelength (λp4) selected from the wavelength range of 380-500 nm, such as from the wavelength range of 400-490 nm. Further, the fourth light generating device may be configured to generate fourth device light. The fourth device light may especially comprise the fourth light source light. In embodiments, for at least three of (a) the first light source light, (b) the second light source light, (c) the third light source light, and (d) the fourth light source light may apply that their respective peak emission wavelengths may mutually differ by at least 10 nm, such as by at least 15 nm. Further, the light generating system may be configured to generate system light. Especially, the system light may comprise one or more of the first device light, the second device light, the third device light, and the fourth device light. Further, the control system may be configured to control, in an operational mode of the light generating system, a spectral power distribution of the system light in the wavelength range of 380-780 nm by individually controlling the first light2024PF80384

[0016] 4

[0017] generating device, the second light generating device, and the one or more of the third light generating device and the fourth light generating device. Hence, in specific embodiments, the invention provides a light generating system comprising: (i) a first light generating device, (ii) a second light generating device, (iii) one or more of a third light generating device and a fourth light generating device, and (iv) a control system, wherein: (A) the first light generating device comprises a first solid state light source and a first luminescent converter; wherein the first solid state light source is configured to generate first light source light having a first peak emission wavelength (kpi) selected from the wavelength range of 400-490 nm; (B) the first luminescent converter is configured in a light receiving relationship with the first solid state light source; wherein the first luminescent converter comprises a first luminescent material; wherein the first luminescent material is configured to convert part of the first light source light received by the first luminescent converter into first luminescent material light; wherein the first luminescent material light has a first centroid wavelength (λc1) selected from the wavelength range of 600-660 nm; (C) the first light generating device is configured to generate first device light; wherein the first device light comprises the first luminescent material light and part of the first light source light; (D) the second light generating device comprises a second solid state light source and a second luminescent converter; wherein the second solid state light source is configured to generate second light source light having a second peak emission wavelength (λp2) selected from the wavelength range of 400-490 nm; (E) the second luminescent converter is configured in a light receiving relationship with the second solid state light source; wherein the second luminescent converter comprises a second luminescent material; wherein the second luminescent material is configured to convert part of the second light source light received by the second luminescent converter into second luminescent material light; wherein the second luminescent material light has a second centroid wavelength (λc2) selected from the wavelength range of 490-590 nm; (F) the second light generating device is configured to generate second device light; wherein the second device light comprises the second luminescent material light and part of the second light source light; (G) the third light generating device comprises a third solid state light source and a third luminescent converter; wherein the third solid state light source is configured to generate third light source light having a third peak emission wavelength (λp3) selected from the wavelength range of 400-490 nm; (H) the third luminescent converter is configured in a light receiving relationship with the third solid state light source; wherein the third luminescent converter comprises a third luminescent material; wherein the third luminescent material is configured to convert2024PF80384

[0018] 5

[0019] part of the third light source light received by the third luminescent converter into third luminescent material light; (I) the third light generating device is configured to generate third device light; wherein the third device light comprises the third luminescent material light and part of the third light source light; wherein the third device light is white light having a correlated color temperature selected from the range of 1700-8000 K; (J) the fourth light generating device comprises a fourth solid state light source; wherein the fourth solid state light source is configured to generate fourth light source light having a fourth peak emission wavelength (λp4) selected from the wavelength range of 400-490 nm; (K) the fourth light generating device is configured to generate fourth device light; wherein the fourth device light comprises the fourth light source light; (L) for at least three of (a) the first light source light, (b) the second light source light, (c) the third light source light, and (d) the fourth light source light applies that their respective peak emission wavelengths mutually differ by at least 20 nm; (M) the light generating system is configured to generate system light; wherein the system light comprises one or more of the first device light, the second device light, the third device light, and the fourth device light; and (N) the control system is configured to control, in an operational mode of the light generating system, a spectral power distribution of the system light in the wavelength range of 380-780 nm by individually controlling the first light generating device, the second light generating device, and the one or more of the third light generating device and the fourth light generating device.

[0020] Such a light generating system, wherein for at least three of λp1, λp2, λp3, and λp4may apply that they mutually differ by > 20 nm, may provide the benefit that a blue light peak in a spectral power distribution of the system light may be relatively broad and low (i.e., the system light may comprise broad-band blue emission). That is, the spectral power of the system light in the wavelength range of 400-490 nm may be spread out over a larger wavelength range, thereby reducing the probability of damaging the photoreceptor cells and / or retinal pigment epithelial cells in the eye of an observer. Hence, such a light generating system may be relatively safe. Further, such a light generating system may facilitate adjusting the position of the blue light peak in the spectral power distribution of the system light, by individually controlling the intensities of the first, second, third, and fourth device light in the system light. Additionally or alternatively, such a light generating system, especially such a control system, may facilitate adjusting one or more of a color rendering index (CRI), correlated color temperature (CCT), and color point of the system light by individually controlling the first light generating device, second light generating device, and one or more of the third light generating device and the fourth light generating device. Hence,2024PF80384

[0021] 6

[0022] the light generating system of the invention may especially provide a CCT and color tunable light source having less-intense broad-band blue emission.

[0023] The first light generating device may comprise the first solid state light source. Similarly, the second light generating device may comprise the second solid state light source. Additionally, the third light generating device may comprise the third solid state light source. Further, the fourth light generating device may comprise the fourth solid state light source. The first solid state light source, second solid state light source, third solid state light source, and fourth solid state light source may be individually selected from the group comprising a light emitting diode (LED), a laser diode, a superluminescent diode, and a (stacked) multi -junction light emitting diode, though other options may also be possible (see below). Further, the first solid state light source may be configured to generate first light source light having a first peak emission wavelength (λp1). Similarly, the second solid state light source may be configured to generate second light source light having a second peak emission wavelength (λp2). Additionally, the third solid state light source may be configured to generate third light source light having a third peak emission wavelength (λp3). Further, the fourth solid state light source may be configured to generate fourth light source light having a fourth peak emission wavelength (Xp4). In embodiments, the first peak emission wavelength (λp1), the second peak emission wavelength (Zp2), the third peak emission wavelength (λp3), and the fourth peak emission wavelength (Xp4) may be individually selected from the wavelength range of 380-500 nm, such as from the wavelength range of 400-490 nm, especially from the wavelength range of 420-490 nm, like from the wavelength range of 430-490 nm. Hence, the first, second, third, and fourth light source light may be one of violet light and blue light, such as especially blue light. The term “violet light”, and similar terms, may especially relate to light having a wavelength in the range of about 380-440 nm. The term “blue light”, and similar terms, may especially relate to light having a wavelength in the range of about 440-490 nm. The term “peak emission wavelength” may refer to the wavelength where the radiometric emission spectrum of the light source reaches its maximum, i.e., the peak emission wavelength may denote the wavelength at which the largest (emission intensity) value is found in a graph of the spectral power distribution.

[0024] In embodiments, the first peak emission wavelength (λp1) may be selected from the wavelength range of 430-490 nm, such as from the wavelength range of 440-475 nm, especially from the wavelength range of 450-470 nm. Hence, in specific embodiments, the first peak emission wavelength (λp1) may be selected from the wavelength range of 440-475 nm. A first peak wavelength (Api) selected from such a range may be especially suited to2024PF80384

[0025] 7

[0026] excite the first luminescent material. Further, a human eye may be especially sensitive to light having a wavelength selected from the range of 440-475 nm, thereby increasing the luminous efficacy of the first light generating device.

[0027] In embodiments, the fourth light source light may be relatively shortwavelength (violet) light. That is, the fourth peak emission wavelength (λp4) may be selected from the wavelength range of 390-430 nm, such as from the wavelength range of 400-420 nm, especially from the wavelength range of 405-415 nm. Alternatively, the fourth light source light may be relatively long-wavelength (blue) light. That is, the fourth peak emission wavelength (λp4) may be selected from the wavelength range of 460-500 nm, such as from the wavelength range of 470-490 nm, especially from the wavelength range of 475-485 nm. Hence, in specific embodiments, one of the following may apply: (i) the fourth peak emission wavelength (λp4) may be selected from the wavelength range of 400-420 nm, and (ii) the fourth peak emission wavelength (λp4) may be selected from the wavelength range of 470-490 nm. Short-wavelength (violet) fourth light source light may facilitate providing (in combination with one or more of the first, second, and third device light) white system light with improved white rendering. Alternatively, long-wavelength (blue) fourth light source light may be less potentially damaging to the human eye. Further, light with a (peak) wavelength selected from the wavelength range of 470-490 nm may be especially suitable to stimulate melanopsin photoreceptors in the human eye, thereby stimulating wakefulness and alertness in humans.

[0028] In embodiments, |λp1- λp2| < 10 nm may apply, such as |λp1- λp2| < 5 nm, especially |λp1- λp2| < 2 nm, including (essentially) λp1= λp2. Alternatively, in embodiments, |λp1- λp2| > 10 nm may apply, such as |λp1- λp2| > 15 nm, especially |λp1- λp2| > 20 nm. Further, in embodiments, (the light generating system may comprise the third light generating device, wherein) |λp1- λp3| < 10 nm may apply, such as |λp1- λp3| < 5 nm, especially |λp1- λp3| < 2 nm, including (essentially) λp1= λp3. Alternatively, in embodiments, |λp1- λp3| > 10 nm may apply, such as |λp1- λp3| > 15 nm, especially |λp1- λp3| > 20 nm. Further, in embodiments (the light generating system may comprise the fourth light generating device, wherein) |λp1- λp4| < 10 nm may apply, such as |λp1- λp4| < 5 nm, especially |λp1- λp4| < 2 nm, including (essentially) λp1= λp4. Alternatively, in embodiments, |λp1- λp4| > 10 nm may apply, such as |λp1- λp4| > 15 nm, especially |λp1- λp4| > 20 nm.

[0029] Further, in embodiments, (the light generating system may comprise the third light generating device, wherein) |kp2 - kps | < 10 nm may apply, such as |kp2 - kps | < 5 nm,2024PF80384

[0030] 8

[0031] especially |λp2- λp3| < 2 nm, including (essentially) Xp2 = Xps. Alternatively, in embodiments, |λp2- λp3| > 10 nm may apply, such as |λp2- λp3| > 15 nm, especially |λp2- λp3| > 20 nm. Further, in embodiments, (the light generating system may comprise the fourth light generating device, wherein) |λp2- λp4| < 10 nm may apply, such as |λp2- λp4| < 5 nm, especially |λp2- λp4| < 2 nm, including (essentially) Xp2 = Xp4. Alternatively, in embodiments, |λp2- λp4| > 10 nm may apply, such as |λp2- λp4| > 15 nm, especially |λp2- λp4| > 20 nm. In embodiments, the light generating system may comprise both the third and fourth light generating devices, wherein | Xp3 - Xp4| < 10 nm may apply, such as |λp3- λp4| < 5 nm, especially |λp3- λp4| < 2 nm, including (essentially) Xp3 = Xp4. Alternatively, in embodiments, |λp3- λp4| > 10 nm may apply, such as |λp3- λp4| > 15 nm, especially |λp3- λp4| > 20 nm.

[0032] For at least three of (a) the first light source light, (b) the second light source light, (c) the third light source light, and (d) the fourth light source light may apply that their respective peak emission wavelengths may mutually differ by at least 10 nm, such as at least 15 nm, especially at least 20 nm, like at least 25 nm. That is, in embodiments, for at least three of λp1, λp2, λp3, and λp4may apply that each peak wavelength may be separated (in a spectral power distribution) from the nearest of the other peak wavelengths of the at least three of pi, Xp2, Xp3, and Xp4 by a distance of > 10 nm, such as > 15 nm, especially > 20 nm, like > 25 nm. Hence, in specific embodiments, for at least three of (a) the first light source light, (b) the second light source light, (c) the third light source light, and (d) the fourth light source light may apply that their respective peak emission wavelengths may mutually differ by at least 20 nm. A light generating system wherein the peak wavelengths of at least three of the light source lights mutually differ by at least 20 nm may provide the benefit that a blue light peak in a spectral power distribution of the system light may be relatively broad and low. Especially, such system light may better simulate natural light and reducing the chance for negative health effects due to high-intensity (narrow-band) blue emission.

[0033] In embodiments, the light generating system may comprise the first, second, and third light generating devices, wherein λp1, λp2, and λp3may mutually differ by > 10 nm, such as > 15 nm, especially > 20 nm. Alternatively, the light generating system may comprise the first, second, and fourth light generating devices, wherein λp1, λp2, and λp4may mutually differ by > 10 nm, such as > 15 nm, especially > 20 nm. Yet, in embodiments, the light generating system may comprise the first, second, third, and fourth light generating devices, wherein one of the following may apply: (i) λp1, λp2, and λp3may mutually differ by > 10 nm, such as > 15 nm, especially > 20 nm, (ii) λp1, λp2, and λp4may mutually differ by > 102024PF80384

[0034] 9

[0035] nm, such as > 15 nm, especially > 20 nm, (iii) λp1, λp3, and λp4may mutually differ by > 10 nm, such as > 15 nm, especially > 20 nm, and (iv) λp2, λp3, and λp4may mutually differ by >10 nm, such as > 15 nm, especially > 20 nm. Further, (the light generating system may comprise the first, second, third, and fourth light generating devices, wherein) for (all of) the first light source light, the second light source light, the third light source light, and the fourth light source light may apply that their respective peak emission wavelengths may mutually differ by at least 10 nm, such as at least 15 nm, especially at least 20 nm, like at least 25 nm. Hence, in specific embodiments, for the first light source light, the second light source light, the third light source light, and the fourth light source light may apply that their respective peak emission wavelengths may mutually differ by at least 15 nm. Such embodiments may facilitate further broadening a peak in the wavelength range of 400-490 nm in the spectral power distribution of the system light. Further, such embodiments may facilitate providing system light comprising one or more of the first, second, third, and fourth device light, wherein said system light may better simulate a spectrum of natural (sun)light.

[0036] Hence, for at least three, such as all, of kpi, λp2, λp3, and λp4may apply that they may mutually differ. In embodiments, the first peak emission wavelength (λp1) may be (one of) the smallest wavelength(s). That is, in embodiments, λp1< λp2, λp1< λp3, and λp1< λp4may apply. Additionally or alternatively, the second peak emission wavelength (kp2) may be (one of) the largest wavelength(s). That is, in embodiments, λp2> λp1, λp2> λp3, and λp2> λp4may apply. Hence, in specific embodiments, one or more may apply of: (i) λp1< λp2, λp1< λp3, and λp1< λp4; and (ii) λp2> λp1, λp2> λp3, and λp2> λp4. Selecting kpi to be (one of) the smallest peak wavelength(s) may provide the benefit that the color gamut of the system light comprising the first device light may be increased. Further, selecting kp2 to be (one of) the largest peak wavelength(s) may facilitate providing system light with a larger color gamut, as the difference between λp2and λc2may be relatively small, such that for the first device light and the third device light a wider spectral power distribution may be provided.

[0037] The second peak emission wavelength (kp2) may be equal to or larger than the first peak emission wavelength (kpi). That is, in embodiments, λp1< λp2may apply. Further, the light generating system may (at least) comprise the third light generating device, wherein the second peak emission wavelength (kp2) may be equal to or smaller than the third peak emission wavelength (λp3). That is, in embodiments, λp2< λp3may apply. Further, kpi < λp2< λp3may apply (wherein at least three of kpi, λp2, λp3, and λp4may mutually differ). Hence, in specific embodiments, kpi < kp2 < kps (may apply). An embodiment such as kpi < kp2 < kps may provide the benefit that the first and second luminescent materials may be excited2024PF80384

[0038] 10

[0039] using smaller peak wavelengths, where the first and second luminescent materials may have relatively higher absorbances. Further, such an embodiment may provide the benefit that the relatively larger peak emission wavelength of the white third device light may relatively better stimulate melanopsin photoreceptors in the human eye, thereby stimulating wakefulness and alertness in humans.

[0040] Hence, λp1< λp2may apply. Further, the light generating system may (at least) comprise the fourth light generating device. In such embodiments, the second peak emission wavelength (λp2) may be equal to or smaller than the fourth peak emission wavelength (Ap4). That is, in embodiments, λp2< λp4may apply. Further, in specific embodiments, the light generating system may comprise (both) the third light generating device and the fourth light generating device. In such embodiments, (also) λp2< λp4may apply. Further, for the third peak emission wavelength (Ap^) one of the following may apply: (i) λp3< λp1< λp2< λp4, (ii) λp1< λp3< λp2< λp4, (iii) λp1< λp2< λp3< λp4, and (iv) λp1< λp2< λp4< λp3. Hence, in specific embodiments, the light generating system may comprise the third light generating device and the fourth light generating device, wherein λp1< λp2< λp4. Selecting the fourth peak emission wavelength (Ap ) to be the largest peak emission wavelength may provide the benefit that the shorter wavelengths, which may be more efficient for exciting luminescent materials, may be used in the first and second light generating device.

[0041] As indicated above, the fourth peak emission wavelength (Ap ) may be selected from the group of short-wavelength (violet) light and long-wavelength (blue) light. Hence, the fourth peak emission wavelength (Ap ) may be (i) the smallest of λp1, λp2, λp3, and λp4, or (ii) the largest of Apn, Ap2, Ap3, and Ap. Further, the second peak emission wavelength (Ap>2) may be larger than or smaller than the first peak emission wavelength (Apn). Hence, in embodiments, one of the following may apply: (i) λp4< λp1< λp2, (ii) λp4< λp2< λp1, (iii) λp1< λp2< λp4, and (iv) λp2< λp1< λp4. Further, one of λp1< λp4< λp2and λp2< λp4< λp1may apply. Yet, especially, one of (i) λp2< λp1< λp4, and (ii) λp4< λp1< λp2may apply. Hence, in specific embodiments, the light generating system may comprise the fourth light generating device, wherein (i) λp2< λp1< λp4, or (ii) λp4< λp1< λp2. As indicated above, a large fourth peak emission wavelength (Ap ) may facilitate stimulating melanopsin photoreceptors in the human eye with the fourth device light. Alternatively, a small fourth peak emission wavelength (Ap ) may provide the benefit that a color gamut of the system light may be improved, and / or that a blue representation of the system light may be improved (in embodiments wherein the system light comprises the fourth device light).2024PF80384

[0042] 11

[0043] As indicated above, A,pi may be the smallest peak emission wavelength, and Xp2 may be the largest peak emission wavelength. Additionally, one of kps < Ap and Ap < Ap>3 may apply. Hence, in embodiments, Ap>i < Apu < Apu < Apu may apply. Alternatively, Ap>i < Apu < Ap>3 < Apu may apply. Yet, in embodiments, Ap>i > Apu may apply. Especially, Ap>i may be the largest peak emission wavelength. Further, Apu may be the smallest peak emission wavelength. In such embodiments, Apu < Apu < Apu < Ap>i may apply. Alternatively, Apu < Apu < Apu < Ap>i may apply. Hence, in specific embodiments, one of the following may apply: (i) Apu < Apu < Apu < Apu; (ii) Apu < Apu < Apu < Apu; and (iii) Apu < Apu < Apu < Apu. As indicated above, selecting Apu to be the smallest peak emission wavelength and Apu to be the largest peak emission wavelength may facilitate providing system light with a relatively large color gamut. Alternatively, selecting Apu to be the largest peak emission wavelength may provide the benefit of extending the lifetime of the first luminescent material, which may be less stable towards short- wavelength (violet or blue) light.

[0044] The first light generating device may further comprise a first luminescent converter, configured in a light receiving relationship with the first solid state light source. Similarly, the second light generating device may comprise a second luminescent converter, configured in a light receiving relationship with the second solid state light source. Further, the third light generating device may comprise a third luminescent converter, configured in a light receiving relationship with the third solid state light source. Hence, the first, second, and third luminescent converters may be configured downstream of respectively the first, second, and third solid state light source. The terms “downstream” and “upstream” relate to an arrangement of items or features relative to the propagation of the light from a light generating means (here especially the solid state light sources), wherein relative to a first position within a beam of light from the light generating means, a second position in the beam of light closer to the light generating means is “upstream”, and a third position within the beam of light further away from the light generating means is “downstream”. The (first, second, and / or third) luminescent converters may be configured in physical contact with and covering (a light escape surface of) their respective solid state light source. In such embodiments, the (first, second, and / or third) luminescent converters may be configured as a coating (on the respective solid state light source), or as a self-supporting luminescent body. Further, the (first, second, and / or third) luminescent converters may be configured as a self-supporting luminescent body, wherein the (first, second, and / or third) luminescent converters may be configured (physically separated from and) at a non-zero distance from (the light escape surface of) the (respective) solid state light source.2024PF80384

[0045] 12

[0046] The first luminescent converter may comprise a first luminescent material. Similarly, the second luminescent converter may comprise a second luminescent material. Further, the third luminescent converter may comprise a third luminescent material. Here below, some general embodiments relating to the luminescent materials are provided. The term “luminescent material” may refer to a material that can convert first radiation, e.g. one or more of UV radiation, violet radiation, blue radiation, and green radiation, into second radiation. Herein, UV (ultraviolet) may refer to a wavelength selected from the range of 190-380 nm, such as 200-380 nm, though other wavelengths may also be possible. The term “green light” may relate to light having a wavelength in the range of 490-560 nm. The first radiation and second radiation may have different spectral power distributions, with the second radiation generally having a spectral power distribution at larger wavelengths than the first radiation (i.e. “down-conversion”). In embodiments, the “luminescent material” may especially refer to a material that can convert radiation into visible and / or infrared light. The terms “visible light” or “visible emission”, and similar terms, refer to light having one or more wavelengths in the range of about 380-780 nm. Further, IR (infrared) may especially refer to radiation having a wavelength selected from the range of 780-3000 nm, such as 780-2000 nm, though other wavelengths may be possible. In general, the luminescent material will be a down converter, i.e. radiation with a smaller wavelength is converted into radiation with a larger wavelength (λex<λem). In embodiments, the term “luminescence” may refer to one or more of phosphorescence and fluorescence. Instead of the term “luminescence”, also the term “luminescent material light” or “emission” may be applied. Hence, the terms “first radiation” and “second radiation” may refer to excitation radiation and emission (radiation), respectively. The term “luminescent material” may also refer to a plurality of different luminescent materials, such as a luminescent material composition. Instead of the term “luminescent material” also the term “phosphor” may be applied. These terms are known to the person skilled in the art. Examples of luminescent materials are indicated below.

[0047] In embodiments, luminescent materials may be selected from garnets and nitrides, especially doped with trivalent cerium or divalent europium, respectively. The term “nitride” may also refer to oxynitride or nitridosilicate, etc. Alternatively or additionally, the luminescent material(s) may be selected from silicates, especially doped with divalent europium. In embodiments, the luminescent material may comprise a divalent europium comprising oxynitride luminescent material. Further, in embodiments, the luminescent material may comprise a divalent europium comprising nitride luminescent material.2024PF80384

[0048] 13

[0049] In embodiments, the luminescent material may comprise a luminescent material of the type A₃B₅O₁₂:Ce, wherein A comprises one or more of Y, La, Gd, Tb and Lu, and wherein B comprises one or more of Al, Ga, In and Sc; and wherein the light source light may comprise blue light source light (i.e., a cerium comprising garnet material). Especially, A may comprise one or more of Y, Gd and Lu, such as especially one or more of Y and Lu. Further, B may comprise one or more of Al and Ga, such as at least Al, especially entirely Al. Embodiments of garnets include A3B5O12garnets, wherein A comprises at least yttrium (Y) or lutetium (Lu) and wherein B comprises at least aluminum (Al). Such garnets may be doped with one or more of cerium (Ce) and praseodymium (Pr); especially however with Ce. Especially, B may comprise Al, with optionally gallium (Ga) and / or scandium (Sc) and / or indium (In) up to 20%, such as up to 10%, of B (i.e. the B ions consist of > 90 mole% of Al and < 10 mole% of one or more of Ga, Sc, and In). B may especially comprise up to 10% gallium. Alternatively, B and O may at least partly be replaced by Si and N. The element A may be selected from the group consisting of Y, gadolinium (Gd), terbium (Tb) and Lu. Gd and / or Tb may only be present up to 20% of A. In a specific embodiment, the garnet luminescent material comprises (Y1-xLux)3B5O12:Ce, wherein 0 < x < 1. The term “: Ce”, indicates that part of the metal ions (i.e. in the garnets part of the “A” ions) in the luminescent material is replaced by Ce, as is known to the person skilled in the art. Ce may replace A for < 10%; in general, the Ce concentration will be in the range of 0.1 to 4%, especially 0.1 to 2% (relative to A). Ce in garnets is substantially or only in the trivalent state, as is known to the person skilled in the art.

[0050] In specific embodiments, the luminescent material may comprise (YxiA’X2CeX3)3(AlyiB’y2)5Oi2. Here, A’ comprises one or more elements selected from the group consisting of lanthanides, and B’ comprises one or more elements selected from the group of Ga, In and Sc, wherein xl+x2+x3=l, wherein x3>0, wherein 0<x2+x3<0.2, wherein yl+y2=l, wherein 0<y2<0.2. Especially, x3 is selected from the range of 0.001-0.1. Note that in embodiments x2=0. Alternatively or additionally, in embodiments y2=0.

[0051] In embodiments, the luminescent material may comprise a luminescent material of the type A3Si6N11:Ce3+, wherein A comprises one or more of Y, La, Gd, Tb and Lu, such as in embodiments one or more of La and Y. Alternatively or additionally, the luminescent material may comprise one or more of MS: Eu2+, M2Si5N8:Eu2+, MAlSiN3:Eu2+, Ca2AlSi3O2N5:Eu2+, etc., wherein M comprises one or more of Ba, Sr and Ca, such as at least Sr. Hence, in embodiments, the luminescent material may comprise one or more materials selected from the group consisting of (Ba, Sr, Ca)S: Eu, (Ba, Sr, Ca)AlSiN3: Eu and2024PF80384

[0052] 14

[0053] (Ba, Sr, Ca)2SisN8: Eu. In these compounds, europium (Eu) is substantially or only divalent, and replaces one or more of the indicated divalent cations, as is known to the person skilled in the art. In general, Eu may be present in amounts of < 10% of the cation, such as in the range of 0.5-10%, especially in the range of 0.5-5% relative to the cation(s) it replaces. The term “: Eu”, indicates that part of the metal ions (indicated by M) is replaced by Eu. For instance, with 2% Eu in CaAlSi Eu, the correct formula could be (Cao.98Euo.o2)AlSiN3.

[0054] The term “luminescent material” herein especially relates to inorganic luminescent materials. Alternatively or additionally, also other luminescent materials may be applied. For instance quantum dots and / or organic dyes may be applied and may optionally be embedded in transmissive matrices like e.g. polymers, like PMMA, or polysiloxanes, etc..

[0055] In embodiments, the luminescent material may comprise a luminescent material of the type M1-xLi3-2yAl1+2y-zSizO4-4y-zN4y+z:Eux. Herein, M may comprise one or more of magnesium (Mg), calcium (Ca), strontium (Sr), and barium (Ba), such as especially one or more of Ca, Sr, and Ba. Hence, M1-xLi3-2yAl1+2y-zSizO4-4y-zN4y+z:Euxmay especially refer to (Mg, Ca, Sr, Ba)i-xLi3-2yAli+2y-zSizO4-4y-zN4y+z: Eux. Such a luminescent material may be indicated as an SLA-type phosphor, or SLA phosphor. SLA phosphors may be described in US2021171827A1, which is hereby herein incorporated by reference. In embodiments, in M1-xLi3-2yAl1+2y-zSizO4-4y-zN4y+z:Eux, one or more of the following may apply: (i) 0 < x < 0.1, such as 0.0005 < x < 0.08, especially 0.001 < x < 0.05, (ii) 0 < y < 1, such as 0 < y < 0.75, especially 0 < y < 0.6, and (iii) 0 < z < 0.1, such as 0 < z < 0.07, especially 0 < z < 0.05. Hence, Eu may replace less than 10% of M, and may substantially or only be in the divalent state (Eu2+), as is known to the person skilled in the art. Further, SiN may replace A1O up to 10 mole%. In embodiments, an SLA phosphor may crystallize in a UCr4C4 type crystal structure. Hence, the luminescent material may comprise a luminescent material of the type M1-xLi3-2yAl1+2y-zSizO4-4y-zN4y+z:Eux, wherein M comprises one or more of Ca, Sr, and Ba, wherein 0 < x < 0.04, wherein 0 < y < 1, wherein 0 < z < 0.05, and wherein y + z < 1. In embodiments, part of the Al in the SLA phosphor may be replaced by Ga. Hence, the luminescent material may comprise a luminescent material of the type M1-xLi3-2y(Al1-bGab)1+2y-zSizO4-4y-zN4y+z:Eux, wherein M may comprise one or more of Mg, Ca, Sr, and Ba, and x, y, and z may be as indicated above. Such a luminescent material may be indicated as an SLGA phosphor, especially when b > 0. In embodiments, b > 0 may apply, such as b > 0.05, especially b > 0.1, like b > 0.15. Additionally or alternatively, b < 0.6 may apply, such as b < 0.5, especially b < 0.4, like b < 0.3. Hence, 0 < b < 0.6 may apply, such as 0.05 < b < 0.5, especially 0.1 < b < 0.3, like 0.15 < b < 0.3.2024PF80384

[0056] 15

[0057] Further, the luminescent material may comprise a (divalent europium comprising) SiAlON phosphor, such as selected from the group comprising (a) Si12-m-nAlm+nOnN16-n:Eu2+(a-Si A1ON), (b) Si6-nAlnOnN8-n:Eu2+, wherein 0 ≤ n ≤ 4.2 (β-SiAlON), and (c) Si2-nAlnO1+nN2-n:Eu2+, wherein 0 ≤ n ≤ 0.2 (O-SiAlON).

[0058] In embodiments, the luminescent material may comprise a tetravalent manganese-comprising luminescent material, i.e., a luminescent material doped with tetravalent manganese (Mn4+). Especially, in embodiments, the luminescent material may comprise a luminescent material of the type M’xM2-2xAX6 doped with Mn4+, wherein M’ comprises an alkaline earth cation, M comprises an alkaline cation, and x may be selected from the range of 0-1, wherein A comprises a tetravalent cation, e.g. comprising one or more of silicon and titanium, and wherein X comprises a monovalent anion, at least comprising fluorine. Such luminescent materials may herein also be indicated as “KSiF” or “KSF”, regardless of the composition of M’, M, A, and X. A luminescent material of the type M’XM2-2XAXe: Mn4+is amongst others described in WO2013121355A1, which is herein incorporated by reference. In embodiments, M’ may comprise one or more of Mg, Sr, Ca and Ba, especially Sr and / or Ba. Further, M may comprise one or more of sodium (Na), potassium (K) and rubidium (Rb). Optionally, M may (further) comprise one or more of ammonium (NH4+), lithium (Li), and cesium (Cs). Especially, M comprises at least K. Alternatively, M comprises at least Rb. The phrase “wherein M comprises at least K” indicates that of all M cations in a mole M’xM2-2xAX6, a fraction comprises K+and an optionally remaining fraction comprises one or more other monovalent (alkaline) cations (see also below). In an embodiment, preferably > 80% (i.e. 80% of all moles of the type M), such as > 90%, especially > 95% of M consists of one or more of K, Na, and Rb, such as one or more of K and Rb. In embodiments, x may be zero. The M’xM2-2xAX6 luminescent material may have the hexagonal phase or the cubic phase. In embodiments, a combination of alkaline cations M may be applied. Additionally or alternatively, a combination of alkaline earth cations M’ may be applied. For instance, KRb0.5Sr0.25AX6might be applied. In M’xM2-2xAX6: Mn4+, part of the tetravalent cation A is being replaced by manganese. Hence, M’xM2-2xAX6 doped with Mn4+may also be indicated as M’xM2-2xAi-mMnmX6 (or M’xM2-2xAX6: Mn4+). The mole% of Mn (i.e. the percentage it replaces A) may be in the range of 0.1-15 %, especially 1-12 %. Hence, 0.001 < m < 0.15 may apply, especially 0.01 < m < 0.12. Hence, the hexafluorosilicate is doped or activated with manganese (Mn4+).

[0059] In embodiments, A may comprise a tetravalent cation, and preferably at least comprises silicon (Si). A may optionally (further) comprise one or more of titanium (Ti),2024PF80384

[0060] 16

[0061] germanium (Ge), tin (stannum) (Sn) and zinc (Zn). Further, A may comprise one or more of zirconium (Zr), and hafnium (Hf). Preferably, > 80%, such as > 90%, like > 95%, of A consists of Si. As indicated above, X relates to a monovalent anion, but at least comprises fluorine (F). Other monovalent anions that may be present may be selected from the group consisting of chlorine (Cl), bromine (Br), and iodine (I). Preferably, > 80%, such as > 90%, like > 95%, of X consists of F. In an embodiment, M’xM2-2xAX6 comprises K2SiF6. In another embodiment, M’xM2-2xAX6 comprises KRbSiF6. In specific embodiments, the indication M’xM2-2xAX6 may refer to one or more of (K,Rb)2SiF6:Mn4+, (K,Rb)2TiF6:Mn4+, K2(Si,Ti)F6:Mn4+, and Rb2(Si,Ti)F6:Mn4+, such as one or more of K2TiF6:Mn4+, of K2SiF6:Mn4+, and of Rb2SiF6:Mn4+. As can be derived from the above, “(Si, Ti)” may indicate one or more of Si and Ti. Hence, in specific embodiments, the luminescent material may comprise one or more of (K,Rb)2SiF6:Mn4+and K2(Si,Ti)F6:Mn4+.

[0062] Hence, when M (or A) in a chemical formula refers to n different elements, this may imply that the formula may comprise for the M (or A) position essentially any permutation of the n different elements. For instance, when M comprises one or more of Ba, Sr, Ca, i.e. n=3, this may imply that in the formula Ba, Sr, Ca, (BaxSry), (BaxCay), (CaxSry), or (BaxSryCaz), may be available, wherein x+y+z=l. Further, indications like “K, Rb” or Ba, Sr, Ca, and similar indications (see also above), may indicate one or more of such elements. Hence, (K,Rb)2SiF6:Mn4+, may e.g. refer to K2SiF6: Mn4+, Rb2SiF6:Mn4+, or (KxRby)2SiF6:Mn4+. Also herein in general x+y=l. Hence, when M (or A) may refer to n different elements, with n being at least two, 2n-l permutations may in principle be possible.

[0063] In embodiments, the first luminescent converter may comprise a first luminescent material. In embodiments, the first luminescent material may comprise one or more of a divalent europium comprising oxynitride luminescent material and a divalent europium comprising nitride luminescent material. Additionally or alternatively, the first luminescent material may comprise a SiAlON phosphor. Additionally, or alternatively, the first luminescent material may comprise a luminescent material of the type M1-xLi3-2y(Al1-bGab)1+2y-zSizO4-4y-zN4y+z:Eux, wherein M comprises one or more of Mg, Ba, Sr, and Ca, wherein 0 < x < 0.1, wherein 0 < y < 1, wherein 0 < z < 0.1, and wherein 0 < b < 0.6.

[0064] Additionally or alternatively, the first luminescent material may comprise a luminescent material of the type M’xM2-2xAX6: Mn4+, wherein M’ comprises an alkaline earth cation, M comprises a monovalent cation, and x is in the range of 0-1, wherein A comprises a tetravalent cation, comprising one or more of Si, Ti, and Ge, and wherein X comprises a monovalent anion, at least comprising F (see also above). Hence, the first luminescent2024PF80384

[0065] 17

[0066] material may comprise one or more luminescent materials selected from the group of a divalent europium comprising oxynitride luminescent material, a divalent europium comprising nitride luminescent material, a SiAlON phosphor, a luminescent material of the type M1-xLi3-2y(Al1-bGab)1+2y-zSizO4-4y-zN4y+z:Eux, and a luminescent material of the type M’xM2-2xAX6: Mn4+, such as especially (at least) a luminescent material of the type M’XM2-2xAXe: Mn4+. In such embodiments, the first peak emission wavelength (kpi) may especially be selected from the wavelength range of 430-490 nm, such as from the wavelength range of 440-475 nm, especially from the wavelength range of 450-470 nm. Hence, in specific embodiments, the first luminescent material may comprise a luminescent material of the type M’xM2-2xAX6: Mn4+, wherein M’ comprises an alkaline earth cation, M comprises a monovalent cation, and x is in the range of 0-1, wherein A comprises a tetravalent cation, comprising one or more of silicon, titanium, and germanium, and wherein X comprises a monovalent anion, at least comprising fluorine; and wherein the first peak emission wavelength (kpi) may be selected from the wavelength range of 440-475 nm. Such a first luminescent material may especially provide red luminescent material light. Further, such a first luminescent material may facilitate improving a CRI R9 (score) of the system light.

[0067] The first luminescent material may comprise one or more further (types of) luminescent materials, such as selected from the (types of) luminescent materials provided above. Additionally or alternatively, the first luminescent material may comprise one or more luminescent materials of the type M’xM2-2xAX6: Mn4+, wherein the one or more luminescent materials of the type M’xM2-2xAX6: Mn4+may differ in the composition of M and / or the composition of A. Especially, the first luminescent material may consist for > 80 wt.%, such as > 85 wt.%, especially > 90 wt.%, like > 95 wt.%, including 100 wt.%, of luminescent materials of the type M’xM2-2xAX6: Mn4+. As indicated above, M may comprise an alkaline cation. Especially, M may comprise one or more of Rb, K, and Na, such as especially K and / or Na. Further, A may comprise one or more of Si and Ti, such as at least Si, or such as at least Ti. Hence, the first luminescent material may comprise (KyNai-y)2(SixTii-x)F6: Mn4+. In such embodiments, 0 < y < 1 may apply, such as 0.1 < y < 1, especially 0.2 < y < 0.9. Additionally or alternatively, in such embodiments, 0 < x < 1 may apply, such as 0.1 < x < 1, especially 0.2 < x < 0.9. Hence, in specific embodiments, the first luminescent material may comprise (KyNai-y)2(SixTii-x)F6: Mn4+, wherein 0 < y < 1 and 0 < x < 1. Such a first luminescent material may especially provide relatively narrow-band emission in the (orange-)red wavelength range. Further, such a first luminescent material may facilitate that a position of a first centroid wavelength (λc1) may be tuned by adjusting one or more of y and x.2024PF80384

[0068] 18

[0069] The first luminescent material may be configured to convert part of the first light source light received by the first luminescent converter into first luminescent material light. Especially, the first luminescent material may be configured to convert > 75%, such as > 80%, especially > 82%, like > 85%, of the first light source light received by the first luminescent converter into first luminescent material light. Additionally or alternatively, the first luminescent material may be configured to convert < 99%, such as < 98%, especially < 97%, like < 95%, of the first light source light received by the first luminescent converter into first luminescent material light. Hence, the first luminescent material may be configured to convert 75-99%, such as 80-98%, especially 82-97%, like 85-95%, of the first light source light received by the first luminescent converter into first luminescent material light.

[0070] The first luminescent material light may have a first centroid wavelength (λc1). The term “centroid wavelength”, also indicated as c, is known in the art, and refers to the wavelength value (in nm) where half of the light energy is at shorter and half the energy is at longer wavelengths. It is the wavelength that divides the integral of a spectral power distribution into two equal parts as expressed by the formula λc= Σ λI(λ) / (Σ I(λ)), where the summation is over the wavelength range of interest, and 1(A) is the spectral energy density (i.e. the integration of the product of the wavelength and the intensity over the emission band normalized to the integrated intensity). In embodiments, the first centroid wavelength (λc1) may be selected from the range of 590-670 nm, such as from the range of 600-660 nm, especially from the range of 610-650 nm, like from the range of 620-640 nm. Hence, the first luminescent material light may comprise, such as be, one or more of orange light and red light, such as especially red light. The terms “orange light” or “orange emission”, and similar terms, may especially relate to light having a wavelength in the range of about 590-620 nm. The terms “red light” or “red emission”, and similar terms, may especially relate to light having a wavelength in the range of about 620-780 nm.

[0071] Further, the first luminescent material light may comprise at least one emission band having a first full width at half maximum FWHMi of < 50 nm, such as < 40 nm, especially < 35 nm, like < 25 nm. Additionally or alternatively, the first full width at half maximum FWHMi may be > 2 nm, such as > 5 nm, especially > 7 nm. The first luminescent material light may comprise a plurality of emission bands, wherein at least one band (such as all bands) may have the first full width at half maximum FWHMi. The term “emission band” may refer to the emission (spectral power distribution) resulting from a radiative transition of electrons from (vibrational levels of) a first higher-energy excited state to (vibrational levels of) a second lower-energy (ground) state, wherein a larger number of vibrational levels in2024PF80384

[0072] 19

[0073] (one or more of) the first excited state and second (ground) state results in a broader emission band (spanning a larger wavelength range). Further, the term “full width at half maximum” (or “FWHM”) refers to the width of (the spectral power distribution of) the emission band at half the maximum intensity of said emission band.

[0074] The first light generating device may be configured to generate first device light. The first device light may comprise the first luminescent material light. Further, the first device light may comprise part of the first light source light. Especially, the first device light may have a spectral power distribution, wherein > 1%, such as > 3%, especially > 5%, of the spectral power in the wavelength range of 380-780 nm may be in the wavelength range of 380-490 nm (i.e., provided by the first light source light). Additionally or alternatively, the first device light may have a spectral power distribution, wherein < 20%, such as < 18%, especially < 16%, of the spectral power in the wavelength range of 380-780 nm may be in the wavelength range of 380-490 nm. Further, the first device light may have a spectral power distribution, wherein 1-20%, such as 3-18%, especially 5-16%, of the spectral power in the wavelength range of 380-780 nm may be in the wavelength range of 380-490 nm. Hence, in specific embodiments, the first device light may have a spectral power distribution, wherein 3-18% of the spectral power in the wavelength range of 380-780 nm may be in the wavelength range of 380-490 nm. Such first device light may especially provide mostly red light, yet may also contribute to a (violet-)blue peak in the spectral power distribution of the system light. Hence, such first device light may facilitate broadening a blue emission peak of the system light.

[0075] As indicated above, the second luminescent converter may comprise the second luminescent material. The second luminescent material may comprise a divalent europium comprising thiogallate. The term “divalent europium comprising thiogallate” may herein refer to a luminescent material of the type MwAuXv:Eu2+1-w, wherein M comprises one or more of Mg, Sr, Ca, and Ba, wherein A comprises Ga and optionally one or more of Al, boron (B), In, Sc, Lu, and Y, wherein X comprises one or more of S, Se, O, and tellurium (Te), (such as especially at least S), wherein 0.01 < w < 0.99, wherein 2 < u < 4, and wherein 4 < v < 7. Additionally or alternatively, the second luminescent material may comprise a divalent europium comprising thioaluminate. The term “divalent europium comprising thioalluminate” may herein refer to a luminescent material of the type MwAuXv:Eu2+1-w, wherein M comprises one or more of Mg, Sr, Ca, and Ba, wherein A comprises Al and optionally one or more of Ga, boron (B), In, Sc, Lu, and Y, such as at least Al, wherein X comprises one or more of S, Se, O, and tellurium (Te), (such as especially at least S), wherein2024PF80384

[0076] 20

[0077] 0.01 < w < 0.99, wherein 2 < u < 4, and wherein 4 < v < 7. Additionally or alternatively, the second luminescent material may comprise a divalent europium comprising silicate (such as (Sri.xBax)2SiO4: Eu2+, wherein 0 < x < 1, such as especially 0 < x < 1). Additionally or alternatively, the second luminescent material may comprise a luminescent material of the type Si6-nAlnOnN8-n:Eu2+, wherein 0 ≤ n ≤ 4.2 (i.e., a β-SiAlON phosphor). Additionally or alternatively, the second luminescent material may comprise a luminescent material of the type A3B5O12:Ce, wherein A comprises one or more of Y, La, Gd, Tb and Lu, and wherein B comprises one or more of Al, Ga, In and Sc. Hence, in embodiments, the second luminescent material may comprise one or more luminescent material selected from the group of divalent europium comprising thiogallates, divalent europium comprising thioaluminates, divalent europium comprising silicates, luminescent materials of the type Si6-nAlnOnN8-n: Eu2+, wherein 0 < n < 4.2, and luminescent materials of the type A3B5O12:Ce, such as especially a luminescent material of the type A₃B₅O₁₂:Ce, wherein A comprises one or more of Y, La, Gd, Tb and Lu, and wherein B comprises one or more of Al, Ga, In and Sc. In such embodiments, the second peak emission wavelength (λp2) may especially be selected from the wavelength range of 420-490 nm, such as from the wavelength range of 430-490 nm. Hence, in specific embodiments, the second luminescent material may comprise a luminescent material of the type A₃B₅O₁₂:Ce, wherein A comprises one or more of Y, La, Gd, Tb and Lu, and wherein B comprises one or more of Al, Ga, In and Sc; wherein the second peak emission wavelength (λp2) may be selected from the wavelength range of 430-490 nm. Such a second luminescent material may be relatively thermally and / or chemically stable. Further, such a second luminescent material may relatively efficiently convert second light source light into second luminescent material light.

[0078] The second luminescent material may be configured to convert part of the second light source light received by the second luminescent converter into second luminescent material light. Especially, the second luminescent material may be configured to convert > 75%, such as > 80%, especially > 82%, like > 85%, of the second light source light received by the second luminescent converter into second luminescent material light.

[0079] Additionally or alternatively, the second luminescent material may be configured to convert < 99%, such as < 98%, especially < 97%, like < 95%, of the second light source light received by the second luminescent converter into second luminescent material light. Hence, the second luminescent material may be configured to convert 75-99%, such as 80-98%, especially 82-97%, like 85-95%, of the second light source light received by the second luminescent converter into second luminescent material light.2024PF80384

[0080] 21

[0081] The second luminescent material light may have a second centroid wavelength (λc2). In embodiments, the second centroid wavelength (λc2) may be selected from the range of 480-600 nm, such as from the range of 490-590 nm, especially from the range of 500-570 nm. Hence, in embodiments, the second luminescent material light may comprise, such as be, one or more of green light and yellow light, such as especially green light. The term “yellow light”, and similar terms, may especially relate to light having a wavelength in the range of about 560-590 nm. The second centroid wavelength ( C2) may be smaller than the first centroid wavelength (λc1). Especially, in embodiments, λc₁-λc₂ ≥ 10 nm (may apply), such as λc₁-λc₂ ≥ 20 nm, especially λc₁-λc₂ ≥ 30 nm. Additionally or alternatively, in embodiments, λc₁-λc₂ ≤ 140 nm (may apply), such as λc₁-λc₂ ≤ 120 nm, especially λc₁-λc₂ ≤ 100 nm.

[0082] The second luminescent material light may comprise at least one emission band having a second full width at half maximum FWHM2 of > 50 nm, such as > 60 nm, especially > 70 nm. Additionally or alternatively, the second full width at half maximum FWHM2 may be < 200 nm, such as < 175 nm, especially < 150 nm. In embodiments, the second luminescent material light may comprise a plurality of emission bands, wherein at least one band may have the second full width at half maximum FWHM2. Alternatively, the second luminescent material light may comprise a single emission band, wherein said emission band may have the second full width at half maximum FWHM2.

[0083] The second light generating device (comprising the second luminescent converter) may be configured to generate second device light. The second device light may comprise the second luminescent material light. Further, the second device light may comprise part of the second light source light. Especially, the second device light may have a spectral power distribution, wherein > 1%, such as > 3%, especially > 5%, of the spectral power in the wavelength range of 380-780 nm may be in the wavelength range of 380-490 nm (i.e., provided by the second light source light). Additionally or alternatively, the second device light may have a spectral power distribution, wherein < 20%, such as < 18%, especially < 16%, of the spectral power in the wavelength range of 380-780 nm may be in the wavelength range of 380-490 nm. Further, the second device light may have a spectral power distribution, wherein 1-20%, such as 3-18%, especially 5-16%, of the spectral power in the wavelength range of 380-780 nm may be in the wavelength range of 380-490 nm. Hence, in specific embodiments, the second device light may have a spectral power distribution, wherein 3-18% of the spectral power in the wavelength range of 380-780 nm may be in the wavelength range of 380-490 nm. Such second device light may especially provide mostly green(-yellow) light, yet may also contribute to a (violet-)blue peak in the spectral power2024PF80384

[0084] 22

[0085] distribution of the system light. Hence, such second device light may facilitate broadening a blue emission peak of the system light.

[0086] As indicated above, the third luminescent converter may comprise the third luminescent material. The third luminescent material may comprise one or more (types of) luminescent material. Especially, the third luminescent material may comprise a primary third luminescent material and a secondary third luminescent material. In embodiments, the primary third luminescent material may comprise one or more of a divalent europium comprising oxynitride luminescent material and a divalent europium comprising nitride luminescent material. Additionally or alternatively, the primary third luminescent material may comprise a SiAlON phosphor. Additionally, or alternatively, the primary third luminescent material may comprise a luminescent material of the type M1-xLi3-2y(Al1-bGab)1+2y-zSizO4-4y-zN4y+z:Eux, wherein M comprises one or more of Mg, Ba, Sr, and Ca, wherein 0 < x < 0.1, wherein 0 < y < 1, wherein 0 < z < 0.1, and wherein 0 < b < 0.6.

[0087] Additionally or alternatively, the primary third luminescent material may comprise a luminescent material of the type M’xM2-2xAX6: Mn4+, wherein M’ comprises an alkaline earth cation, M comprises a monovalent cation, and x is in the range of 0-1, wherein A comprises a tetravalent cation, comprising one or more of Si, Ti, and Ge, and wherein X comprises a monovalent anion, at least comprising F. Hence, the primary third luminescent material may comprise one or more luminescent materials selected from the group of a divalent europium comprising oxynitride luminescent material, a divalent europium comprising nitride luminescent material, a SiAlON phosphor, a luminescent material of the type M1-xLi3-2y(Al1-bGab)1+2y-zSizO4-4y-zN4y+z:Eux, and a luminescent material of the type M’xM2-2xAX6: Mn4+.

[0088] The primary third luminescent material may be configured to convert part of the third device light received by the third luminescent converter into primary third luminescent material light. The primary third luminescent material light may have a primary third centroid wavelength ( c3,i). Especially, the primary third centroid wavelength ( c3,i) may be selected from the range provided above for the first centroid wavelength (λc1).

[0089] Further, the primary third luminescent material light may comprise at least one emission band having a primary third full width at half maximum FWHM3.1, selected from the range provided above for the first full width at half maximum FWHMi.

[0090] The secondary third luminescent material may comprise a divalent europium comprising thiogallate. Additionally or alternatively, the secondary third luminescent material may comprise a divalent europium comprising thioaluminate. Additionally or alternatively, the secondary third luminescent material may comprise a divalent europium2024PF80384

[0091] 23

[0092] comprising silicate. Additionally or alternatively, the secondary third luminescent material may comprise a luminescent material of the type Si6-nAlnOnN8-n:Eu2+, wherein 0 ≤ n ≤ 4.2 (i.e., a β-SiAlON phosphor). Additionally or alternatively, the secondary third luminescent material may comprise a luminescent material of the type A3B5O12:Ce, wherein A comprises one or more of Y, La, Gd, Tb and Lu, and wherein B comprises one or more of Al, Ga, In and Sc. Hence, in embodiments, the second luminescent material may comprise one or more luminescent material selected from the group of divalent europium comprising thiogallates, divalent europium comprising thioaluminates, divalent europium comprising silicates, luminescent materials of the type Si6-nAlnOnN8-n: Eu2+, wherein 0 < n < 4.2, and luminescent materials of the type A3B5O12:Ce, wherein A comprises one or more of Y, La, Gd, Tb and Lu, and wherein B comprises one or more of Al, Ga, In and Sc.

[0093] The secondary third luminescent material may be configured to convert part of the third device light received by the third luminescent converter into secondary third luminescent material light. The secondary third luminescent material light may have a secondary third centroid wavelength (λc3,2). Especially, the secondary third centroid wavelength (λc3,2) may be selected from the range provided above for the second centroid wavelength (λc₂). Further, the secondary third luminescent material light may comprise at least one emission band having a secondary third full width at half maximum FWHM32 selected from the range provided above for the second full width at half maximum FWHM2.

[0094] In embodiments, the third luminescent material, comprising (especially consisting of) the primary third luminescent material and the secondary third luminescent material, may be configured to generate third luminescent material light. In embodiments, the third luminescent material light may comprise, such as consist of, the primary third luminescent material light and the secondary third luminescent material light. Hence, in specific embodiments, the third luminescent material may comprise a primary third luminescent material and a secondary third luminescent material, wherein: (A) the primary third luminescent material may comprise one or more luminescent materials selected from the group of divalent europium comprising oxynitride luminescent materials, divalent europium comprising nitride luminescent materials, SiAlON phosphors, luminescent materials of the type M1-xLi3-2y(Al1-bGab)1+2y-zSizO4-4y-zN4y+z:Eux, wherein M comprises one or more of Mg, Ba, Sr, and Ca, wherein 0 < x < 0.1, wherein 0 < y < 1, wherein 0 < z < 0.1, and wherein 0 < b < 0.6, and luminescent materials of the type M’xM2-2xAX6: Mn4+, wherein M’ comprises an alkaline earth cation, M comprises a monovalent cation, and x is in the range of 0-1, wherein A comprises a tetravalent cation, comprising one or more of silicon,2024PF80384

[0095] 24

[0096] titanium, and germanium, and wherein X comprises a monovalent anion, at least comprising fluorine; and (B) the secondary third luminescent material may comprise one or more luminescent materials selected from the group of divalent europium comprising thiogallates, divalent europium comprising thioaluminates, divalent europium comprising silicates, luminescent materials of the type Si6-nAlnOnN8-n: Eu2+, wherein 0 < n < 4.2, and luminescent materials of the type A3B5O12:Ce, wherein A comprises one or more of Y, La, Gd, Tb and Lu, and wherein B comprises one or more of Al, Ga, In and Sc. Such a third luminescent material may provide the benefit that the third luminescent material light may comprise both green(-yellow) light and (orange-)red light. Hence, such third luminescent material light may especially have a broad spectral power distribution.

[0097] The third luminescent material may be configured to convert part of the third light source light received by the third luminescent converter into third luminescent material light. Especially, the third luminescent material may be configured to convert > 75%, such as > 80%, especially > 82%, like > 85%, of the third light source light received by the third luminescent converter into third luminescent material light. Additionally or alternatively, the third luminescent material may be configured to convert < 99%, such as < 98%, especially < 97%, like < 95%, of the third light source light received by the third luminescent converter into third luminescent material light. Hence, the third luminescent material may be configured to convert 75-99%, such as 80-98%, especially 82-97%, like 85-95%, of the third light source light received by the third luminescent converter into third luminescent material light. The third luminescent material light may have a spectral power distribution, wherein (i) yi% of the spectral power in the wavelength range of 380-780 nm may be provided by the primary third luminescent material light, and (ii) y2% of the spectral power in the wavelength range of 380-780 nm may be provided by the secondary third luminescent material light. In embodiments, yi > 15% may apply, such as yi > 20%, especially yi > 25%. Additionally or alternatively, yi < 60% may apply, such as yi < 55%, especially yi < 50%. Further, y₂ ≥ 40% may apply, such as y₂ ≥ 45%, especially y₂ ≥ 50%. Additionally or alternatively, y₂ ≤ 85% may apply, such as y₂ ≤ 80%, especially y₂ ≤ 75%. Hence, the third luminescent material light may have a spectral power distribution, wherein (i) 15-60%, such as 20-55%, especially 25-50%, of the spectral power in the wavelength range of 380-780 nm may be provided by the primary third luminescent material light, and (ii) 40-85%, such as 45-80%, especially 50-75%, of the spectral power in the wavelength range of 380-780 nm may be provided by the secondary third luminescent material light.2024PF80384

[0098] 25

[0099] The third light generating device (comprising the third luminescent converter) may be configured to generate third device light. The third device light may comprise the third luminescent material light. Further, the third device light may comprise part of the third light source light. Especially, the third device light may have a spectral power distribution, wherein > 1%, such as > 3%, especially > 5%, of the spectral power in the wavelength range of 380-780 nm may be in the wavelength range of 380-490 nm (i.e., provided by the third light source light). Additionally or alternatively, the third device light may have a spectral power distribution, wherein < 20%, such as < 18%, especially < 16%, of the spectral power in the wavelength range of 380-780 nm may be in the wavelength range of 380-490 nm. Hence, the third device light may have a spectral power distribution, wherein 1-20%, such as 3-18%, especially 5-16%, of the spectral power in the wavelength range of 380-780 nm may be in the wavelength range of 380-490 nm.

[0100] The third device light may thus comprise blue light (from the third light source light), green-yellow light (from the secondary third luminescent material light), and (orange-)red light (from the primary third luminescent material light). Hence, the third device light may especially be white light. The term “white light”, and similar terms, herein, is known to the person skilled in the art. It may especially relate to light having a CCT between 1500 K and 20000 K, such as between 1700 and 20000 K, especially between 2000 and 20000 K, for general lighting especially in the range of 2000-7000 K, such as in the range of 2700-6500 K. In embodiments, the CCT may especially be within 20 SDCM (standard deviation of color matching) from the BBL (black body locus), such as within 15 SDCM from the BBL, especially within 10 SDCM from the BBL, like within 5 SDCM from the BBL. In embodiments, the third device light may especially be white light having a correlated color temperature (CCT) selected from the range of > 1500 K, such as from the range of > 1700 K, especially from the range of > 2000 K. Further, the third device light may have a CCT selected from the range of > 3500 K, such as from the range of > 4000 K, especially from the range of > 4500 K. Additionally or alternatively, the third device light may have a CCT selected from the range of < 8500 K, such as from the range of < 8000 K, especially from the range of < 7500 K. Hence, the third device light may be white light having a CCT selected from the range of 1500-8500 K, such as from the range of 1700-8000 K, especially from the range of 2000-7500 K. Further, the third device light may be white light having a CCT selected from the range of 3500-8500 K, such as from the range of 4000-8000 K, especially from the range of 4500-7500 K. In embodiments, the third device light may further have a color rendering index (CRI) of at least 80, such as at least 85, especially at least 90. The third2024PF80384

[0101] 26

[0102] device light may have a CRI in the range of 80-95, such as in the range of 80-97, especially in the range of 80-99. Hence, in specific embodiments, (the light generating system may comprise the third light generating device, wherein) the third device light may have a spectral power distribution, wherein 3-18% of the spectral power in the wavelength range of 380-780 nm may be in the wavelength range of 380-490 nm; wherein the third device light may have a color rendering index of at least 85. Such third device light may especially provide a combination of blue, green-yellow, and (orange-)red light, thereby providing white light. Further, third device light with a CRI of at least 85 may facilitate providing (system) light with a relatively good color representation.

[0103] Further, in embodiments, the light generating system may comprise the fourth light generating device. The fourth light generating device may be configured to generate fourth device light. The fourth device light may comprise the fourth light source light.

[0104] Especially, the fourth device light may have a spectral power distribution, wherein > 90%, such as > 95%, especially > 98%, including (essentially) 100%, of the spectral power in the wavelength range of 380-780 nm may be provided by the fourth light source light. The fourth device light may have a fourth device centroid wavelength ( ca4). In embodiments, the fourth device centroid wavelength (Xcd4) may be selected from the wavelength range of 380-500 nm, such as from the wavelength range of 400-490 nm, especially from the wavelength range of 420-490 nm, like from the wavelength range of 430-490 nm. Hence, the fourth device light may be one of violet light and blue light, such as especially blue light. Further, the fourth device light may have a spectral power distribution, wherein > 85%, such as > 90%, especially > 95%, like > 98%, including (essentially) 100%, of the spectral power in the wavelength range of 380-780 nm may be in the wavelength range of 400-490 nm.

[0105] Alternatively, the fourth device light may have a spectral power distribution, wherein < 99%, such as < 98%, especially < 95%, may be in the wavelength range of 400-490 nm. Hence, in specific embodiments, (the light generating system may comprise the fourth light generating device, wherein) the fourth device light may have a fourth device centroid wavelength ( ca4), wherein the fourth device centroid wavelength (λcd4) may be selected from the wavelength range of 400-490 nm; wherein the fourth device light may have a spectral power distribution, wherein at least 90% of the spectral power in the wavelength range of 380-780 nm may be in the wavelength range of 400-490 nm. Such fourth device light may especially provide (violet or) blue light. Hence, such fourth device light may facilitate increasing a relative intensity of light in the wavelength range of 400-490 nm in the system light.2024PF80384

[0106] 27

[0107] As indicated above, the light generating system may be configured to generate system light. The system light may comprise one or more of the first device light, the second device light, the third device light, and the fourth device light. In a first operational mode of the light generating system, the system light may consist of the first device light, wherein the system light may be (orange-)red light. In a second operational mode of the light generating system, the system light may consist of the second device light, wherein the system light may be green(-yellow) light. In a third operational mode of the light generating system, the system light may consist of the third device light, wherein the system light may be white light.

[0108] Further, in a fourth operational mode of the light generating system, the system light may consist of the fourth device light, wherein the system light may be (violet or) blue light. In an operational mode of the light generating system, the system light may comprise the third device light and one or more of the first, second, and fourth device light, wherein the system light may be white light. In another operational mode of the light generating system, the system light may comprise the third device light and one or more of the first, second, and fourth device light, wherein the system light may be colored light (with a color point selected from the CIE 1931 color space). Yet, in an operational mode of the light generating system, the system light may comprise two or more of the first, second, and fourth device light, wherein the system light may be colored light. Yet, in an operational mode of the light generating system, the system light may comprise two or more of the first, second, and fourth device light, wherein the system light may be white light. In an operational mode of the light generating system, the system light may comprise the first, second, and third device light. In a further operational mode of the light generating system, the system light may comprise the first, second, and fourth device light. In a further operational mode of the light generating system, the system light may comprise the first, second, third, and fourth device light, wherein the system light may be colored light or white light.

[0109] Hence, in an operational mode of the light generating system, the system light may be white light. Especially, the system light may be white light having a CCT selected from the range of > 1300 K, such as from the range of > 1500 K, especially from the range of > 1700 K. Further, the system light may have a CCT selected from the range of > 2300 K, such as from the range of > 2700 K, especially from the range of > 3000 K. Additionally or alternatively, the system light may have a CCT selected from the range of < 8500 K, such as from the range of < 8000 K, especially from the range of < 7500 K. Further, the system light may have a CCT selected from the range of < 4500 K, such as from the range of < 4000 K, especially from the range of < 3500 K. Hence, in an operational mode of the light generating2024PF80384

[0110] 28

[0111] system, the system light may be white light having a CCT selected from the range of 1300-8500 K, such as from the range of 1500-8000 K, especially from the range of 1700-7500 K. Further, in an operational mode of the light generating system, the system light may be white light having a CCT selected from the range of 2300-4500 K, such as from the range of 2700-4000 K, especially from the range of 3000-3500 K. In embodiments, the system light may, in said operational mode, further have a CRI of at least 75, such as at least 80, especially at least 85, like at least 90. The system light may have a CRI in the range of 80-95, such as in the range of 80-97, especially in the range of 80-99. Hence, in specific embodiments, in an operational mode of the light generating system, the system light may be white light having a correlated color temperature selected from the range of 1500-8000 K. Such a range for the CCT of the system light may provide the benefit that the system light may be used both for mood lighting (low CCT) and office lighting (high CCT). Hence, such a light generating system may especially be versatile.

[0112] As indicated above, the light generating system may comprise (both) the third light generating device and the fourth light generating device. In such embodiments, |λp3 - λp4| ≥ 10 nm, such as |λp3 - λp4| ≥ 15 nm, especially |λp3 - λp4| ≥ 20 nm may apply. Further, in such embodiments, the third device light may be white light having a CCT selected from the range of 4000-8500 K, such as from the range of 4500-8000 K, especially from the range of 5000-7500 K. Additionally, (in an operational mode of the light generating system,) the system light may comprise the third device light and the fourth device light. In such embodiments, (and in such an operational mode,) the system light may especially be white light having a CCT selected from the range of 2300-4500 K, such as from the range of 2500-4000 K, especially from the range of 2700-3500 K. Further, (in said operational mode of the light generating system,) the system light may have a spectral power distribution, wherein: (i) X3% of the spectral power in the wavelength range of 380-780 nm may be provided by the third device light, and (ii) X4% of the spectral power in the wavelength range of 380-780 nm may be provided by the fourth device light. In said operational mode of the light generating system, the system light may have a (predetermined) starting first ratio R1s = X3s / X4s. In R1s = X3s / X4s, X3s may refer to a starting contribution of the third device light to the spectral power of the system light in the wavelength range of 380-780 nm, and X4s may refer to a starting contribution of the fourth device light to the spectral power of the system light in the wavelength range of 380-780 nm. Further, in said operational mode, the control system may be configured to vary a first ratio R1 = X3 / X4 over a range of 0.8*R1s - 1.2*R1s, such as over a range of 0.9*R1s - 1.1*R1s, especially over a range of 0.95*R1s - 1.05*R1s, while maintaining2024PF80384

[0113] 29

[0114] a CCT of the system light. Herein, the term “maintaining a CCT of the system light” may indicate that, while varying the first ratio Ri, the CCT of the system light may deviate < 200 K, such as < 150 K, especially < 125 K, like < 100 K, from a starting CCT of the system light (at the starting first ratio Ris). That is, the control system may be configured to maintain the CCT of the system light within a (predetermined) range having a width of 400 K, such as 300 K, especially 250 K, like 200 K, while varying the first ratio R1. Further, the control system may specially be configured to vary the first ratio R1 while maintaining the CCT of the system light in the (predetermined) range by individually controlling the third light generating device, the fourth light generating device, and one or more of the first light generating device and the second light generating device. Hence, in specific embodiments, the light generating system may comprise the third light generating device and the fourth light generating device; wherein the third device light may be white light having a correlated color temperature selected from the range of 4500-8000 K; wherein the system light may comprise the third device light and the fourth device light; wherein the system light may be white light having a correlated color temperature selected from the range of 2500-4000 K; wherein the system light may have a spectral power distribution, wherein: (i) X3% of the spectral power in the wavelength range of 380-780 nm may be provided by the third device light, and (ii) X4% of the spectral power in the wavelength range of 380-780 nm may be provided by the fourth device light; wherein, in an operational mode of the light generating system: (i) the system light may have a starting first ratio R1s = X3s / X4s; and (ii) the control system may be configured to vary a first ratio R1 = X3 / X4 over a range of 0.9*R1s - 1.1*R1s while maintaining a correlated color temperature of the system light within a range having a width of 300 K by individually controlling the third light generating device, the fourth light generating device, and one or more of the first light generating device and the second light generating device. A light generating system wherein the ratio between the third and fourth device light in the system light may be varied at a constant CCT may provide the benefit that the position and / or width of the blue peak in the system light may be varied while maintaining a desired or predetermined CCT. Further, such a light generating system may facilitate adjusting the CRI of the system light at a constant CCT, thereby improving e.g. a red color representation while maintaining a CCT of the system light.

[0115] Hence, the light generating system may comprise a control system. The control system may especially be configured to individually control the first light generating device, the second light generating device, and the one or more of the third light generating device and the fourth light generating device. The term “controlling” and similar terms2024PF80384

[0116] 30

[0117] especially refer at least to determining the behavior or supervising the running of an element. Hence, herein the term “controlling” and similar terms may include imposing behavior on an element and / or monitoring the element. The controlling of the element can be done with a control system. The control system and the element may thus at least temporarily, or permanently, functionally be coupled. The element may comprise the control system. The control system and element may not be physically coupled. Control can be done via wired and / or wireless control. A control system may comprise or may be functionally coupled to a user interface. The control system may also be configured to receive and execute instructions from a remote control. The control system may be controlled via an App on a device, such as a portable device. In such embodiments the control system of the light generating system may be a slave control system. The light generating system may also comprise means for communicating with other systems or devices, such as on the basis of Bluetooth, Thread, WIFI, LiFi, ZigBee, BLE or WiMAX, or another wireless technology. The control system may control in dependence of one or more of an input signal of a user interface, a sensor signal (of a sensor), and a timer. The term “timer” may refer to a clock and / or a predetermined time scheme.

[0118] The control system may be configured to control one or more of a spectral power distribution, an intensity, a CCT, a CRI, and a color point of the system light (by individually controlling the first light generating device, the second light generating device, and the one or more of the third light generating device and the fourth light generating device). Especially, the control system may be configured to control, in an operational mode of the light generating system, a spectral power distribution of the system light in the wavelength range of 380-780 nm by individually controlling the first light generating device, the second light generating device, and the one or more of the third light generating device and the fourth light generating device. Further, the control system may be configured to control, in an operational mode of the light generating system, a width and / or peak position of a blue light peak in the spectral power distribution of the system light by individually controlling the first light generating device, the second light generating device, and the one or more of the third light generating device and the fourth light generating device (wherein the width of the blue light peak may be a full width at half maximum of the blue light peak).

[0119] In embodiments, the light generating system may comprise a LED package. The term “LED package” may refer to a housing comprising a solid state light source (e.g. a semiconductor chip) and one or more further (optical and / or electrical) components, such as a luminescent converter, a reflector, a carrier, one or more optical elements (e.g. a lens, a2024PF80384

[0120] 31

[0121] dome, a diffuser, etc.), electrical connective elements (e.g. wiring), a heat sink, a Zener diode, etc.. Especially, the LED package (of the light generating system) may comprise a solid state light source and a luminescent converter. Optionally, the LED package (of the light generating system) may further comprise one or more of a reflector, a carrier, one or more optical elements (e.g. a lens, a dome, a diffuser, etc.), electrical connective elements (e.g. wiring), a heat sink, a Zener diode, and one or more further optical and / or electrical components. In embodiments, the LED package may at least comprise a reflective cup. The term “LED package” may in general language usage also be indicated as simply “LED”. That is, in general language usage, the term “LED” may be used to refer to a LED package. In embodiments, a LED package may comprise a solid state light source (e.g. a semiconductor chip) configured to provide primary radiation, which is used as such, such as e.g. a blue light source, like a blue LED. Such an LED (package), which may not comprise a luminescent material, may be indicated as a direct-color LED (dc-LED). Alternatively, the LED package may comprise a solid state light source configured to provide primary radiation, wherein at least part of the primary radiation may be converted into secondary radiation (e.g. by a luminescent material) within the LED package. Such an LED (package) may especially be indicated as a phosphor converted LED or pc-LED. Herein, the LED package may especially be based on the conversion of light source light by one or more luminescent materials.

[0122] Hence, the LED package may be a pc-LED.

[0123] The LED package (of the light generating system) may comprise (i) the first light generating device, (ii) the second light generating device, and (iii) one or more of the third light generating device and the fourth light generating device. In embodiments, each of the first light generating device, second light generating device, and one or more of the third and fourth light generating device may be configured as a (separate) LED package.

[0124] Alternatively, the first light generating device, the second light generating device, and the one or more of the third and fourth light generating device may be configured in a (single) LED package. In embodiments, a LED package may comprise multiple sub-packages, wherein each sub-package may be a LED package as described above. Hence, each of the first light generating device, the second light generating device, and the one or more of the third light generating device and the fourth light generating device may be configured as a (separate) LED package in the LED package of the light generating system, wherein the (separate) LED packages may together form a (larger) LED package. Hence, a LED package may comprise one or more LED (sub-)packages. Alternatively, a LED package may comprise one or more compartments, wherein each compartment may comprise a light generating device (wherein2024PF80384

[0125] 32

[0126] the light generating devices on their own may not be configured as a LED package). Hence, in specific embodiments, the light generating system may comprise a LED package, wherein the LED package may comprise (i) the first light generating device, (ii) the second light generating device, and (iii) one or more of the third light generating device and the fourth light generating device. Such a LED package may be relatively compact. Further, such a LED package may facilitate providing system light with a relatively high intensity.

[0127] In alternative embodiments, the light generating system may comprise a Chip-on-Board (CoB). The term “CoB” may especially refer to LED chips in the form of a semiconductor chip that is neither encased nor connected but directly mounted onto a substrate, such as a PCB. Hence, a plurality of light emitting semiconductor light sources may be configured on the same substrate. Especially, a CoB may be a multi-LED chip configured together as a single lighting module. In embodiments, the Chip-on-Board (CoB) of the light generating system may comprise (i) the first light generating device, (ii) the second light generating device, and (iii) one or more of the third light generating device and the fourth light generating device. In embodiments, (the first light generating device of) the CoB may comprise a plurality of the first solid state light source, such as > 2, like > 3, especially > 4, first solid state light sources. Additionally or alternatively, the CoB may comprise < 200, such as < 150, especially < 100, first solid state light sources. Further, (the first light generating device of) the CoB may comprise the first luminescent converter configured on top of the plurality of first solid state light sources. Further, (the second light generating device of) the CoB may comprise a plurality of the second solid state light source, such as > 2, like > 3, especially > 4, second solid state light sources. Additionally or alternatively, the CoB may comprise < 200, such as < 150, especially < 100, second solid state light sources. Further, (the second light generating device of) the CoB may comprise the second luminescent converter configured on top of the plurality of second solid state light sources. Additionally, the CoB may comprise the third light generating device, wherein (the third light generating device of) the CoB may comprise a plurality of the third solid state light source, such as > 2, like > 3, especially > 4, third solid state light sources. Additionally or alternatively, the CoB may comprise < 200, such as < 150, especially < 100, third solid state light sources. Further, (the third light generating device of) the CoB may comprise the third luminescent converter configured on top of the plurality of third solid state light sources. Additionally or alternatively, the CoB may comprise the fourth light generating device, wherein (the fourth light generating device of) the CoB may comprise a plurality of the fourth solid state light source, such as > 2, like > 3, especially > 4, fourth solid state light2024PF80384

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[0129] sources. Additionally or alternatively, the CoB may comprise < 200, such as < 150, especially < 100, fourth solid state light sources. Hence, in specific embodiments, the light generating system may comprise a Chip-on-Board, wherein the Chip-on-Board may comprise (i) the first light generating device, (ii) the second light generating device, and (iii) one or more of the third light generating device and the fourth light generating device. A CoB may be relatively compact. Further, a CoB may facilitate that a plurality of solid state light sources may share a luminescent converter.

[0130] (Additionally or) alternatively, the light generating system may comprise a LED filament. LED filaments as such are known, and are e.g. described in US8400051B2, W02020016058, WO2019197394, etc., which are herein incorporated by reference. A LED filament may comprise (i) a plurality of solid state light sources arranged on (at least a first major surface of) an elongated carrier, and (ii) an elongated encapsulant covering the plurality of solid state light sources and at least part of the elongated carrier. Hereafter, the solid state light sources of the LED filament may be referred to as “LEDs”, but may alternatively comprise laser diodes, superluminescent diodes, or stacked multi -junction diodes. The LED filament may be defined by a filament length LF, a filament width WF, and a filament thickness TF. Further, the LED filament may have relatively high aspect ratios (LF / WF and / or LF / TF), such as > 10, especially > 15, especially > 20. Yet, the aspect ratio (LF / WF and / or LF / TF) may be < 900, such as < 650, especially < 500. In embodiments, the LED filament may be straight. Alternatively, the LED filament may be curved. For instance, the LED filament may have a (2D or 3D) spiraling shape, (like) a helical shape.

[0131] The LED filament may comprise an elongated carrier, configured to support the LEDs. The elongated carrier may e.g. comprise glass, quartz, metal, sapphire, a polymeric material, or a (flexible) metal (e.g., a film or foil). The elongated carrier may be rigid (self-supporting), but may (in polymeric embodiments) also be flexible. Further, the elongated carrier may be light transmissive, or transparent for light, especially visible light. Yet, in embodiments, the carrier may be light reflective, such as reflective for one or more of light source light and luminescent material light. In specific embodiments, the carrier may be diffuse reflective. In embodiments, the (elongated) carrier may comprise a first major surface at a first side of the carrier and a second major surface at a second side of the carrier, opposite to the first side. In embodiments, the LEDs may be arranged on at least one of these surfaces. Hence, in embodiments, at least part of, such as all of, the LEDs may be mounted onto the first major surface. Additionally or alternatively, at least part of the LEDs may be mounted onto the second major surface. Hence, the LEDs may be arranged, mounted and / or2024PF80384

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[0133] mechanically coupled on / to the carrier, wherein the carrier may especially be configured to mechanically and / or electrically support the LEDs. The (plurality of) LEDs may be arranged in an array (on the elongated carrier). In embodiments, the number of LEDs in the array may be selected from the range of 10-2000, such as from the range of 10-1500, especially from the range of 10-1000. In embodiments, the LEDs may be configured in a ID (linear) array. Further, the LEDs may be configured in two ID arrays, one on the first major surface of the elongated carrier and one on the second major surface. A 2D array of LEDs of n*m LEDs may also be possible. In embodiments, 1 < n < 4, such as 1 < n < 3, like 1 < n < 2, and m > n may apply, such as especially m > 4, like m > 6, such as m > 8. Further n / m < 0.2 may apply, like n / m < 0.1, especially n / m < 0.05. In embodiments, the elongated carrier may be light transparent, and the LEDs may be configured on one or more of the first major surface and the second major surface. Alternatively, the elongated carrier may be light reflective, and the LEDs may be configured on both the first major surface and the second major surface.

[0134] The LED filament may comprise an encapsulant. The encapsulant may cover at least part of the elongated carrier, such as at least (part of) one of the first major surface and the second major surface. In general, the encapsulant may be in contact with the elongated carrier and may cover all of the LEDs. The encapsulant may be a continuous coating along the filament length LF, at one or both, such as especially both, of the first major and the second major surface. Further, the encapsulant may at least partly cover the LEDs, such as > 75%, especially > 95%, up to 100%, of the total number of LEDs in the array. In embodiments, the encapsulant configured on the first major surface may be different from the encapsulant configured on the second major surface, such as differ in one or more of a thickness and a luminescent material concentration. The encapsulant may comprise one or more of a luminescent material and a light scattering material. The luminescent material and / or the light scattering material may be configured embedded in an encapsulant material, e.g. a (flexible) polymer material (such as a silicone). Especially, the encapsulant may comprise a luminescent converter. Further, a luminescent converter may be configured as the encapsulant. In embodiments, the (optional) light scattering material may be configured to scatter (or “diffuse”) the light source light, especially in a direction transverse to a normal of the (first and / or second) major surface. In specific embodiments, the light scattering material may comprise light scattering particles, e.g. at least one of BaSO4, A12O3and TiO2particles.

[0135] Hence, the light generating system may comprise a LED filament. The LED filament (of the light generating system) may comprise (i) the first light generating device, (ii) the second light generating device, and (iii) one or more of the third light generating2024PF80384

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[0137] device and the fourth light generating device. In embodiments, each of the light generating devices may be configured as a sub-filament of the LED filament. That is, the LED filament may comprise one or more (especially at least three) sub-filaments, wherein each subfilament may comprise a light generating device. The LED filament may comprise a plurality of the first solid state light source arranged on an elongated carrier. Further, the LED filament may comprise a first elongated encapsulant covering the plurality of first solid state light sources and at least part of the elongated carrier. In embodiments, the first elongated encapsulant may comprise the first luminescent converter. Further, the LED filament may comprise a plurality of the second solid state light source arranged on an elongated carrier. Additionally, the LED filament may comprise a second elongated encapsulant covering the plurality of second solid state light sources and at least part of the elongated carrier. In embodiments, the second elongated encapsulant may comprise the second luminescent converter. Further, the LED filament may comprise the third light generating device, wherein the LED filament may comprise a plurality of the third solid state light source arranged on an elongated carrier. Additionally, the LED filament may comprise a third elongated encapsulant covering the plurality of third solid state light sources and at least part of the elongated carrier. In embodiments, the third elongated encapsulant may comprise the third luminescent converter. Additionally or alternatively, the LED filament may comprise the fourth light generating device, wherein the LED filament may comprise a plurality of the fourth solid state light source arranged on an elongated carrier. Additionally, the LED filament may comprise a fourth elongated encapsulant covering the plurality of fourth solid state light sources and at least part of the elongated carrier. In embodiments, the fourth elongated encapsulant may comprise the fourth luminescent converter. Hence, in specific embodiment, the light generating system may comprise a LED filament, wherein the LED filament may comprise (i) the first light generating device, (ii) the second light generating device, and (iii) one or more of the third light generating device and the fourth light generating device. Further, in specific embodiments, the light generating system may comprise the LED filament, wherein for each of the light generating devices, the LED filament may comprise: (i) a plurality of the respective solid state light sources arranged on an elongated carrier, and (ii) an elongated encapsulant configured in physical contact with and covering the plurality of the respective solid state light sources and at least part of the elongated carrier; wherein the elongated encapsulant may comprise the respective luminescent converter. A LED filament may be suitable for light bulb applications, as a LED filament may better mimic a filament of an incandescent light bulb. Further, especially2024PF80384

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[0139] flexible LED filaments may be used in decorative lighting applications, to provide lighting solutions with various (adjustable) decorative shapes.

[0140] Some general embodiments relating to the light source will be provided next. These embodiments may relate to one or more of the first solid state light source, the second solid state light source, the third solid state light source, and the fourth solid state light source. The term “light source” may in principle relate to any light source known in the art. Especially, the light source may be selected from the group comprising an LED, a laser diode, a superluminescent diode, and a (stacked) multi -junction light emitting diode. The term “light source” may relate to a plurality of (identical or different) light sources, such as 2-2000 light sources (selected from the same bin or at least two different bins, respectively). The term “light source” may refer to a chip scale package(d) (CSP) LED, comprising a single solid state die with provided thereon a luminescent material comprising layer. The term “light source” may also refer to a midpower package, comprising one or more solid state die(s) optionally covered by a luminescent material comprising layer. The die dimensions may be < 2 mm, such as in the range of 0.2-2 mm. The light sources may comprise mini LEDs and / or micro LEDs, such as especially micro LEDs. Herein, the term mini LED refers to solid state light sources having (die) dimensions, especially length and width, selected from the range of 0.1 - 1 mm. Herein, the term micro LED refers to solid state light sources having (die) dimensions, especially length and width, selected from the range of < 100 pm.

[0141] The light source may have a light escape surface. The term escape surface especially relates to that part of the light source, where the light actually leaves or escapes from the light source. The term “light source” may refer to a semiconductor light-emitting device, such as an LED, a resonant cavity LED (RCLED), a vertical cavity laser diode (VCSELs), an edge emitting laser, etc... The term “light source” may also refer to an (activematrix or passive-matrix) organic LED (OLED). Especially, the term “solid state light source” may refer to semiconductor light sources, such as an LED, a laser diode, a superluminescent diode, or a multi -junction diode. In embodiments, the term “laser” may refer to a laser diode (or diode laser), such as especially to a solid-state laser. The terms “laser” or “solid state laser” may refer to one or more of a semiconductor laser diode, such as GaN, InGaN, AlGalnP, AlGaAs, InGaAsP, lead salt, a VCSEL, a quantum cascade laser, a hybrid silicon laser, etc. The term “solid state laser” may thus refer to a laser based on a crystalline or glass body doped with ions, like transition metal ions and / or lanthanide ions, to a fiber laser, to a photonic crystal laser, to a semiconductor laser, etc.2024PF80384

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[0143] The light source may comprise one or more micro-optical elements (array of micro lenses) downstream of a single light source, or downstream of a plurality of light sources. The light source may comprise a LED with on-chip optics. The light source may comprise pixelated single LEDs (with or without optics) (optionally offering on-chip beam steering). In embodiments, the light source may be a dc-LED. Alternatively, the light source may be a pc-LED. Hence, the term “light source” may refer to a light generating element as such, or to a package of the light generating element and one or more optics, like a lens. The term “light source” may also refer to a combination of a light source and an optical filter, which may change the spectral power distribution of the light generated by the light source.

[0144] The light generating system may further be part of or may be applied in e.g. office lighting systems, household application systems, shop lighting systems, home lighting systems, accent lighting systems, spot lighting systems, theater lighting systems, fiber-optics application systems, projection systems, self-lit display systems, pixelated display systems, segmented display systems, warning sign systems, medical lighting application systems, indicator sign systems, decorative lighting systems, portable systems (e.g. a torch), automotive lighting devices, stage-lighting devices, (outdoor) road lighting systems, urban lighting systems, green house lighting systems, horticulture lighting, digital projection, or LCD backlighting. The light generating system (or luminaire) may be part of or may be applied in e.g. optical communication systems or disinfection systems.

[0145] In yet a further aspect, the invention also provides a lamp or a luminaire comprising the light generating system as defined herein. The luminaire may further comprise a housing, optical elements, louvres, etc.. The lamp or luminaire may further comprise a housing enclosing the light generating system. The lamp or luminaire may comprise a light window in the housing or a housing opening, through which the system light may escape from the housing. The lamp may be a portable lamp, such as a torch. In yet a further aspect, the invention also provides a projector device comprising the light generating system as defined herein. Especially, a projector device or “projector” or “image projector” may be an optical device that projects an image (or moving images) onto a surface, such as e.g. a projection screen. The projector device may include one or more light generating systems such as described herein. Further, the invention may provide one or more of a disinfection device, a photochemical reactor, an automotive lighting device, and an optical wireless communication device, comprising the light generating system as defined herein. Further, the invention may provide a lighting fixture, comprising the light generating system as defined herein. Hence, according to a further aspect, the invention provides a lighting2024PF80384

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[0147] device selected from the group of a lamp, a luminaire, a lighting fixture, a projector device, and an automotive lighting device, comprising the light generating system as defined herein. The lighting device may comprise a housing or a carrier, configured to house or support, one or more elements of the light generating system.

[0148] Hence, the invention may provide (a lighting device selected from the group of) a lighting fixture comprising the light generating system as defined herein. Further, the light generating system may comprise a lighting device selected from the group of a lamp, a luminaire, and a lighting fixture, wherein the lamp, luminaire, or lighting fixture may comprise one or more elements of the light generating system, such as the solid state light sources and the luminescent converter, and the light generating system may further comprise e.g. the control system configured to control the device. The term “lighting fixture” may refer to a light emitting system like a moving head, a search light, a stage light, etc.. Such fixtures may have various control options for changing one or more of a direction of the light (e.g. via gimbals or rotary stages), a beam angle / width (e.g. via zoom optics), a beam pattern (e.g. via mechanical selection of an aperture that defines a virtual and patterned source for the further projection optics), the color point of the (system) light (e.g. via mechanical selection of a certain color filter), and a luminous flux, and mostly these may be remotely controllable.

[0149] The terms “light” and “radiation” are herein interchangeably used, unless clear from the context that the term “light” only refers to visible light. The terms “light” and “radiation” may thus refer to UV radiation, visible light, and IR radiation. In specific embodiments, especially for lighting applications, the terms “light” and “radiation” refer to (at least) visible light.

[0150] BRIEF DESCRIPTION OF THE DRAWINGS

[0151] Embodiments of the invention will now be described, by way of example only, with reference to the accompanying schematic drawings in which corresponding reference symbols indicate corresponding parts, and in which:

[0152] Fig. 1 schematically depicts an embodiment of the light generating system; Fig. 2 schematically depicts an embodiment of the system light;

[0153] Figs. 3 A-B schematically depict embodiments of the light generating system; and

[0154] Fig. 4 schematically depicts an embodiment of the lighting device.

[0155] The schematic drawings are not necessarily to scale.2024PF80384

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[0157] DETAILED DESCRIPTION OF THE EMBODIMENTS

[0158] Fig. 1 schematically depicts an embodiment of the light generating system 1000. The light generating system 1000 may comprise (i) a first light generating device 110, (ii) a second light generating device 120, (iii) one or more of a third light generating device 130 and a fourth light generating device 140, and (iv) a control system 300. The first light generating device 110 may comprise a first solid state light source 10 and a first luminescent converter 2100. In Fig. 1, a top view of the first light generating device 110 is depicted, and the first solid state light source 10 is indicated by the dashed box. The first solid state light source 10 may be configured to generate first light source light 11 having a first peak emission wavelength (λp1) selected from the wavelength range of 400-490 nm. Further, the first luminescent converter 2100 may be configured in a light receiving relationship with the first solid state light source 10. The first luminescent converter 2100 may comprise a first luminescent material 210. Especially, the first luminescent material 210 may be configured to convert part of the first light source light 11 received by the first luminescent converter 2100 into first luminescent material light 211. Further, the first luminescent material light 211 may have a first centroid wavelength (λc1) selected from the wavelength range of 600-660 nm. The first light generating device 110 may be configured to generate first device light 111. Especially, the first device light 111 may comprise the first luminescent material light 211 and part of the first light source light 11. The second light generating device 120 may comprise a second solid state light source 20 and a second luminescent converter 2200. In Fig. 1, a top view of the second light generating device 120 is depicted, and the second solid state light source 20 is indicated by the dashed box. The second solid state light source 20 may be configured to generate second light source light 21 having a second peak emission wavelength (λp2) selected from the wavelength range of 400-490 nm. Further, the second luminescent converter 2200 may be configured in a light receiving relationship with the second solid state light source 20. The second luminescent converter 2200 may comprise a second luminescent material 220. Especially, the second luminescent material 220 may be configured to convert part of the second light source light 21 received by the second luminescent converter 2200 into second luminescent material light 221. The second luminescent material light 221 may have a second centroid wavelength (λc2) selected from the wavelength range of 490-590 nm. Further, the second light generating device 120 may be configured to generate second device light 121. Especially, the second device light 121 may comprise the second luminescent material light 221 and part of the second light source light 21. The third light generating device 130 may comprise a third solid state light source 30 and2024PF80384

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[0160] a third luminescent converter 2300. In Fig. 1, a top view of the third light generating device 130 is depicted, and the third solid state light source 30 is indicated by the dashed box. The third solid state light source 30 may be configured to generate third light source light 31 having a third peak emission wavelength (λp3) selected from the wavelength range of 400-490 nm. Further, the third luminescent converter 2300 may be configured in a light receiving relationship with the third solid state light source 30. Especially, the third luminescent converter 2300 may comprise a third luminescent material 230. The third luminescent material 230 may be configured to convert part of the third light source light 31 received by the third luminescent converter 2300 into third luminescent material light 231. Further, the third light generating device 130 may be configured to generate third device light 131. The third device light 131 may comprise the third luminescent material light 231 and part of the third light source light 31. Especially, the third device light 131 may be white light having a correlated color temperature selected from the range of 1700-8000 K. The fourth light generating device 140 may comprise a fourth solid state light source 40. In Fig. 1, a top view of the fourth light generating device 140 is depicted, and the fourth solid state light source 40 is indicated by the dashed box. Optionally, the fourth light generating device 140 may comprise a light transparent coating covering (a light escape surface of) the fourth solid state light source 40, wherein the light transparent coating may comprise a light scattering material. The fourth solid state light source 40 may be configured to generate fourth light source light 41 having a fourth peak emission wavelength (kp4) selected from the wavelength range of 400-490 nm. Further, the fourth light generating device 140 may be configured to generate fourth device light 141. Especially, the fourth device light 141 may comprise the fourth light source light 41. In embodiments, for at least three of (a) the first light source light 11, (b) the second light source light 21, (c) the third light source light 31, and (d) the fourth light source light 41 may apply that their respective peak emission wavelengths may mutually differ by at least 15 nm. Further, the light generating system 1000 may be configured to generate system light 1001. The system light 1001 may comprise one or more of the first device light 111, the second device light 121, the third device light 131, and the fourth device light 141. Further, the control system 300 may be configured to control, in an operational mode of the light generating system 1000, a spectral power distribution of the system light 1001 in the wavelength range of 380-780 nm by individually controlling the first light generating device 110, the second light generating device 120, and the one or more of the third light generating device 130 and the fourth light generating device 140.2024PF80384

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[0162] The third luminescent material 230 may comprise a primary third luminescent material 2310 and a secondary third luminescent material 2320. The primary third luminescent material 2310 may comprise one or more luminescent materials selected from the group of divalent europium comprising oxynitride luminescent materials, divalent europium comprising nitride luminescent materials, SiAlON phosphors, luminescent materials of the type M1-xLi3-2y(Al1-bGab)1+2y-zSizO4-4y-zN4y+z:Eux, and luminescent materials of the type M’xM2-2xAX6: Mn4+(see also above). The secondary third luminescent material 2320 may comprise one or more luminescent materials selected from the group of divalent europium comprising thiogallates, divalent europium comprising thioaluminates, divalent europium comprising silicates, luminescent materials of the type Si6-nAlnOnN8-n: Eu2+, wherein 0 < n < 4.2, and luminescent materials of the type A3B5O12:Ce (see also above).

[0163] Fig. 1 further schematically depicts an embodiment of the light generating system 1000 comprising a LED package 500. The LED package 500 may especially comprise (i) the first light generating device 110, (ii) the second light generating device 120, and (iii) one or more of the third light generating device 130 and the fourth light generating device 140. In the embodiment depicted in Fig. 1, the LED package 500 comprises (both) the third light generating device 130 and the fourth light generating device 140.

[0164] Fig. 2 schematically depicts an embodiment of the system light 1001. One or more of the first device light 111, the second device light 121, and the third device light 131 may have a spectral power distribution, wherein 3-18% of the spectral power in the wavelength range of 380-780 nm may be in the wavelength range of 380-490 nm. Further, the fourth device light 141 may have a spectral power distribution, wherein at least 90% of the spectral power in the wavelength range of 380-780 nm may be in the wavelength range of 400-490 nm. For at least three (such as especially all) of (a) the first light source light 11, (b) the second light source light 21, (c) the third light source light 31, and (d) the fourth light source light 41 may apply that their respective peak emission wavelengths may mutually differ by at least 15 nm, such as by at least 20 nm. As depicted in Fig. 2, Zp2 < Xp4 < Xp3 < kpi may apply. However, as indicated above, the order of and mutual distance between the peak wavelengths may differ, and the invention is not limited to the spectra depicted here.

[0165] Fig. 3 schematically depicts an embodiment of the light generating system 1000 comprising a Chip-on-Board (CoB) 600. The CoB 600 may comprise (i) the first light generating device 110, (ii) the second light generating device 120, and (iii) one or more of the third light generating device 130 and the fourth light generating device 140. Additionally or alternatively, Fig. 3 schematically depicts an embodiment of the light generating system 10002024PF80384

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[0167] comprising a LED filament 400. The LED filament 400 may comprise (i) the first light generating device 110, (ii) the second light generating device 120, and (iii) one or more of the third light generating device 130 and the fourth light generating device 140.

[0168] Fig. 3 A schematically depicts a side view of the CoB 600 and / or the LED filament 400 comprising the first light generating device 110. The CoB 600 and / or the LED filament 400 may comprise a plurality of the first solid state light source 10 arranged on an elongated carrier 5. For the CoB 600, the plurality of first solid state light sources 10 may be configured on a first major surface 51 of the elongated carrier 5. Alternatively, for the LED filament 400, the plurality of first solid state light sources 10 may be configured on one or more of the first major surface 51 and a second major surface 52 of the elongated carrier 5. Would the first solid state light sources 10 be configured on only the first major surface 51, the elongated carrier 5 of the LED filament 400 may be light transmissive. Further, the LED filament 400 may comprise an elongated encapsulant 410 covering the plurality of first solid state light sources 10 and at least part of the elongated carrier 5.

[0169] Fig. 3B schematically depicts a further embodiment of the CoB 600 and / or the LED filament 400, in a cross-sectional view of the CoB 600 and / or the LED filament 400. Here, the CoB 600 and / or the LED filament 400 may especially comprise the third light generating device 130 (and not the fourth light generating device 140, though other embodiments may be possible. The CoB 600 and / or the LED filament 400 may comprise (a first sub-section comprising) the first light generating device 110, (a second sub-section comprising) the second light generating device 120, and (a third sub-section comprising) the third light generating device 130. In embodiments, the light generating system 1000 may comprise the LED filament 400, wherein for each of the light generating devices

[0170] 110,120,130,140, the LED filament 400 may comprise: (i) a plurality of the respective solid state light source 10,20,30,40 arranged on an elongated carrier 5, and (ii) an elongated encapsulant 410 configured in physical contact with and covering the plurality of respective solid state light sources 10,20,30,40 and at least part of the elongated carrier 5. The elongated encapsulant 410 may especially comprise the respective luminescent converter 2100,2200,2300, configured on top of the respective solid state light sources 10,20,30,40.

[0171] Fig. 4 schematically depicts an embodiment of a luminaire 2 comprising the light generating system 1000 as described above. Reference 301 indicates a user interface which may be functionally coupled with the control system 300 of the light generating system 1000. Fig. 4 also schematically depicts an embodiment of lamp 1 comprising the light generating system 1000. Reference 3 indicates a projector device, and reference 4 indicates2024PF80384

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[0173] an automotive lighting device, which may (both) also comprise the light generating system 1000. Hence, Fig. 4 schematically depicts embodiments of a lighting device 1200 selected from the group of a lamp 1, a luminaire 2, a lighting fixture, a projector device 3, and an automotive lighting device 4, comprising the light generating system 1000 as described herein. Lighting device light escaping from the lighting device 1200 is indicated with reference 1201. Lighting device light 1201 may essentially consist of (such as be) system light 1001. Reference 1300 refers to a space, such as a room. Reference 1305 refers to a floor and reference 1310 to a ceiling; reference 1307 refers to a wall.

[0174] The term “plurality” refers to two or more. The terms “substantially” or “essentially”, and similar terms, will be understood by the person skilled in the art. The terms “substantially” or “essentially” may also include embodiments with “entirely”, “completely”, “all”, etc. Hence, in embodiments the adjective substantially or essentially may also be removed. Where applicable, the term “substantially” or the term “essentially” may also relate to 90% or higher, such as 95% or higher, especially 99% or higher, even more especially 99.5% or higher, including 100%. The term “comprise” also includes embodiments wherein the term “comprises” means “consists of’. The term “and / or” especially relates to one or more of the items mentioned before and after “and / or”. For instance, a phrase “item 1 and / or item 2” may relate to one or more of item 1 and item 2. The term “comprising” may refer to “consisting of’, but may also refer to “containing at least the defined species and optionally one or more other species”. Use of the verb “to comprise” and its conjugations does not exclude the presence of elements or steps other than those stated. Unless the context clearly requires otherwise, throughout the description and the claims, the words “comprise”, “comprising”, and the like are to be construed in an inclusive sense as opposed to an exclusive or exhaustive sense; that is to say, in the sense of “including, but not limited to”. The article "a" or "an" preceding an element does not exclude the presence of a plurality of such elements. Furthermore, the terms first, second, third and the like are used for distinguishing between similar elements and not necessarily for describing a sequential or chronological order. It is to be understood that the terms so used are interchangeable under appropriate circumstances and that the embodiments of the invention described herein are capable of operation in other sequences than described or illustrated herein.

[0175] The devices, apparatus, or systems may herein amongst others be described during operation. As will be clear to the person skilled in the art, the invention is not limited to methods of operation, or devices, apparatus, or systems in operation. It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that2024PF80384

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[0177] those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. In the claims, any reference signs placed between parentheses shall not be construed as limiting the claim.

[0178] The invention may be implemented by means of hardware comprising several distinct elements, and by means of a suitably programmed computer. In a device claim, or an apparatus claim, or a system claim, enumerating several means, several of these means may be embodied by one and the same item of hardware. 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. The invention further applies to a device, apparatus, or system comprising one or more of the characterizing features described in the description and / or shown in the attached drawings. The invention further pertains to a method or process comprising one or more of the characterizing features described in the description and / or shown in the attached drawings. The various aspects discussed in this patent can be combined in order to provide additional advantages. Further, the person skilled in the art will understand that embodiments can be combined, and that also more than two embodiments can be combined. Furthermore, some of the features can form the basis for one or more divisional applications.

Claims

2024PF8038445CLAIMS:

1. A light generating system (1000) comprising: (i) a first light generating device (110), (ii) a second light generating device (120), (iii) one or more of a third light generating device (130) and a fourth light generating device (140), and (iv) a control system (300), wherein:the first light generating device (110) comprises a first solid state light source (10) and a first luminescent converter (2100); wherein the first solid state light source (10) is configured to generate first light source light (11) having a first peak emission wavelength, λp1, selected from the wavelength range of 400-490 nm;the first luminescent converter (2100) is configured in a light receiving relationship with the first solid state light source (10); wherein the first luminescent converter (2100) comprises a first luminescent material (210); wherein the first luminescent material (210) is configured to convert part of the first light source light (11) received by the first luminescent converter (2100) into first luminescent material light (211); wherein the first luminescent material light (211) has a first centroid wavelength, ci, selected from the wavelength range of 600-660 nm;the first light generating device (110) is configured to generate first device light (111); wherein the first device light (111) comprises the first luminescent material light (211) and part of the first light source light (11);the second light generating device (120) comprises a second solid state light source (20) and a second luminescent converter (2200); wherein the second solid state light source (20) is configured to generate second light source light (21) having a second peak emission wavelength, λp2, selected from the wavelength range of 400-490 nm;the second luminescent converter (2200) is configured in a light receiving relationship with the second solid state light source (20); wherein the second luminescent converter (2200) comprises a second luminescent material (220); wherein the second luminescent material (220) is configured to convert part of the second light source light (21) received by the second luminescent converter (2200) into second luminescent material light (221); wherein the second luminescent material light (221) has a second centroid wavelength, λc2, selected from the wavelength range of 490-590 nm;2024PF8038446the second light generating device (120) is configured to generate second device light (121); wherein the second device light (121) comprises the second luminescent material light (221) and part of the second light source light (21);the third light generating device (130) comprises a third solid state light source (30) and a third luminescent converter (2300); wherein the third solid state light source (30) is configured to generate third light source light (31) having a third peak emission wavelength, (λp3, selected from the wavelength range of 400-490 nm;the third luminescent converter (2300) is configured in a light receiving relationship with the third solid state light source (30); wherein the third luminescent converter (2300) comprises a third luminescent material (230); wherein the third luminescent material (230) is configured to convert part of the third light source light (31) received by the third luminescent converter (2300) into third luminescent material light (231);the third light generating device (130) is configured to generate third device light (131); wherein the third device light (131) comprises the third luminescent material light (231) and part of the third light source light (31); wherein the third device light (131) is white light having a correlated color temperature selected from the range of 1700-8000 K;the fourth light generating device (140) comprises a fourth solid state light source (40); wherein the fourth solid state light source (40) is configured to generate fourth light source light (41) having a fourth peak emission wavelength, λp4, selected from the wavelength range of 400-490 nm;the fourth light generating device (140) is configured to generate fourth device light (141); wherein the fourth device light (141) has a fourth spectral power distribution, wherein > 90% of the fourth spectral power in the wavelength range of 380-780 nm is provided by the fourth light source light (41);for at least three of (a) the first light source light (11), (b) the second light source light (21), (c) the third light source light (31), and (d) the fourth light source light (41) applies that their respective peak emission wavelengths mutually differ by at least 20 nm;the light generating system (1000) is configured to generate system light (1001); wherein the system light (1001) comprises one or more of the first device light (111), the second device light (121), the third device light (131), and the fourth device light (141); andthe control system (300) is configured to control, in an operational mode of the light generating system (1000), a spectral power distribution of the system light (1001) in the wavelength range of 380-780 nm by individually controlling the first light generating device2024PF8038447(110), the second light generating device (120), and the one or more of the third light generating device (130) and the fourth light generating device (140).

2. The light generating system (1000) according to claim 1, wherein one or more applies of:the first device light (111) has a first spectral power distribution, wherein 3-18% of a first spectral power in the wavelength range of 380-780 nm is in the wavelength range of 380-490 nm;the second device light (121) has a second spectral power distribution, wherein 3-18% of a second spectral power in the wavelength range of 380-780 nm is in the wavelength range of 380-490 nm;the third device light (131) has a third spectral power distribution, wherein 3-18% of a third spectral power in the wavelength range of 380-780 nm is in the wavelength range of 380-490 nm; wherein the third device light (131) has a color rendering index of at least 85; andthe fourth device light (141) has a fourth device centroid wavelength (λcd4), wherein the fourth device centroid wavelength (λcd4) is selected from the wavelength range of 400-490 nm; wherein the fourth device light (141) has a fourth spectral power distribution, wherein at least 90% of a fourth spectral power in the wavelength range of 380-780 nm is in the wavelength range of 400-490 nm.

3. The light generating system (1000) according to any one of the preceding claims, wherein for at least three of (a) the first light source light (11), (b) the second light source light (21), (c) the third light source light (31), and (d) the fourth light source light (41) applies that their respective peak emission wavelengths mutually differ by at least 25 nm.

4. The light generating system (1000) according to any one of the preceding claims, wherein one of the following applies: (i) the fourth peak emission wavelength, λp4, is selected from the wavelength range of 400-420 nm, and (ii) the fourth peak emission wavelength, λp4, is selected from the wavelength range of 470-490 nm.

5. The light generating system (1000) according to any one of the preceding claims 1-4, wherein (i) λp1< λp2, λp1< λp3, and λp1< λp4; or (ii) λp2> λp1, λp2> λp3, and λp2> λp4.2024PF80384486. The light generating system (1000) according to any one of the preceding claims 1-4, wherein one or more applies of:the first peak emission wavelength (λp1) is selected from the wavelength range of 440-475 nm;λp1 < λp2 < λp3; andthe light generating system (1000) comprises the third light generating device (130) and the fourth light generating device (140); wherein λp1 < λp2 < λp4.

7. The light generating system (1000) according to any one of the preceding claims 1-4, wherein for the first light source light (11), the second light source light (21), the third light source light (31), and the fourth light source light (41) applies that their respective peak emission wavelengths mutually differ by at least 25 nm.

8. The light generating system (1000) according to claim 7, wherein one of the following applies: (i) λp2 < λp4 < λp3 < λp1; (ii) λp1 < λp3 < λp4 < λp2; and (iii) λp1 < λp4 < λp3 < λp2.

9. The light generating system (1000) according to any one of the preceding claims 1-4, wherein the light generating system (1000) comprises the fourth light generating device (140), wherein (i) λp2 < λp1 < λp4, or (ii) λp4 < λp1 < λp2.

10. The light generating system (1000) according to any one of the preceding claims, wherein the first luminescent material (210) comprises a luminescent material of the type M’xM2-2xAX6: Mn4+, wherein M’ comprises an alkaline earth cation, M comprises a monovalent cation, and x is in the range of 0-1, wherein A comprises a tetravalent cation, comprising one or more of silicon, titanium, and germanium, and wherein X comprises a monovalent anion, at least comprising fluorine; and wherein the first peak emission wavelength (kpi) is selected from the wavelength range of 440-475 nm.

11. The light generating system (1000) according to any one of the preceding claims, wherein the second luminescent material (220) comprises a luminescent material of the type A3B5O12:Ce, wherein A comprises one or more of Y, La, Gd, Tb and Lu, and2024PF8038449wherein B comprises one or more of Al, Ga, In and Sc; wherein the second peak emission wavelength (λp2) is selected from the wavelength range of 430-490 nm.

12. The light generating system (1000) according to any one of the preceding claims, wherein the third luminescent material (230) comprises a primary third luminescent material (2310) and a secondary third luminescent material (2320), wherein:the primary third luminescent material (2310) comprises one or more luminescent materials selected from the group of divalent europium comprising oxynitride luminescent materials, divalent europium comprising nitride luminescent materials, SiAlON phosphors, luminescent materials of the type M1-xLi3-2y(Al1-bGab)1+2y-zSizO4-4y-zN4y+z:Eux, wherein M comprises one or more of Mg, Ba, Sr, and Ca, wherein 0 < x < 0.1, wherein 0 < y < 1, wherein 0 < z < 0.1, and wherein 0 < b < 0.6, and luminescent materials of the type M’xM2-2xAX6: Mn4+, wherein M’ comprises an alkaline earth cation, M comprises a monovalent cation, and x is in the range of 0-1, wherein A comprises a tetravalent cation, comprising one or more of silicon, titanium, and germanium, and wherein X comprises a monovalent anion, at least comprising fluorine; andthe secondary third luminescent material (2320) comprises one or more luminescent materials selected from the group of divalent europium comprising thiogallates, divalent europium comprising thioaluminates, divalent europium comprising silicates, luminescent materials of the type Si6-nAlnOnN8-n: Eu2+, wherein 0 < n < 4.2, and luminescent materials of the type A3B5O12:Ce, wherein A comprises one or more of Y, La, Gd, Tb and Lu, and wherein B comprises one or more of Al, Ga, In and Sc.

13. The light generating system (1000) according to any one of the preceding claims, wherein the light generating system (1000) comprises the third light generating device (130) and the fourth light generating device (140); wherein the third device light (131) is white light having a correlated color temperature selected from the range of 4500-8000 K; wherein the system light (1001) comprises the third device light (131) and the fourth device light (141); wherein the system light (1001) is white light having a correlated color temperature selected from the range of 2500-4000 K; wherein the system light (1001) has a spectral power distribution, wherein: (i) X3% of the spectral power in the wavelength range of 380-780 nm is provided by the third device light (131), and (ii) X4% of the spectral power in the wavelength range of 380-780 nm is provided by the fourth device light (141); wherein, in an operational mode of the light generating system (1000): (i) the system light (1001) has a2024PF8038450starting first ratio Ris = X3s / X4s; and (ii) the control system (300) is configured to vary a first ratio Ri = X3 / X4 over a range of 0.9*Ris- 1.1 *Ris while maintaining a correlated color temperature of the system light (1001) within a range having a width of 300 K by individually controlling the third light generating device (130), the fourth light generating device (140), and one or more of the first light generating device (110) and the second light generating device (120).

14. The light generating system (1000) according to any one of the preceding claims, wherein one of the following applies:the light generating system (1000) comprises a LED package (500), wherein the LED package (500) comprises (i) the first light generating device (110), (ii) the second light generating device (120), and (iii) one or more of the third light generating device (130) and the fourth light generating device (140);the light generating system (1000) comprises a Chip-on-Board (CoB) (600), wherein the Chip-on-Board (CoB) (600) comprises (i) the first light generating device (110), (ii) the second light generating device (120), and (iii) one or more of the third light generating device (130) and the fourth light generating device (140); andthe light generating system (1000) comprises a LED filament (400), wherein the LED filament (400) comprises (i) the first light generating device (110), (ii) the second light generating device (120), and (iii) one or more of the third light generating device (130) and the fourth light generating device (140).

15. A lighting device (1200) selected from the group of a lamp (1), a luminaire (2), a lighting fixture, a projector device (3), and an automotive lighting device (4), comprising the light generating system (1000) according to any one of the preceding claims.

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